vendor: switch from dep to godep

dep tool vendored too much code (100MB) including tests and unused packages.
godep vendored significantly less (12MB) without tests and unused packages.
The main advantage is that pre-Go1.9 toolchain does not run tests
of all vendor packages now.

38 files changed, 0 insertions, 18468 deletions

diff --git a/vendor/cloud.google.com/go/spanner/admin/database/apiv1/database_admin_client.go b/vendor/cloud.google.com/go/spanner/admin/database/apiv1/database_admin_client.go
deleted file mode 100644
index 95d623059..000000000
--- a/vendor/cloud.google.com/go/spanner/admin/database/apiv1/database_admin_client.go
+++ /dev/null
@@ -1,556 +0,0 @@
-// Copyright 2017, Google Inc. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// AUTO-GENERATED CODE. DO NOT EDIT.
-
-package database
-
-import (
-	"math"
-	"time"
-
-	"cloud.google.com/go/internal/version"
-	"cloud.google.com/go/longrunning"
-	lroauto "cloud.google.com/go/longrunning/autogen"
-	gax "github.com/googleapis/gax-go"
-	"golang.org/x/net/context"
-	"google.golang.org/api/iterator"
-	"google.golang.org/api/option"
-	"google.golang.org/api/transport"
-	iampb "google.golang.org/genproto/googleapis/iam/v1"
-	longrunningpb "google.golang.org/genproto/googleapis/longrunning"
-	databasepb "google.golang.org/genproto/googleapis/spanner/admin/database/v1"
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
-)
-
-var (
-	databaseAdminInstancePathTemplate = gax.MustCompilePathTemplate("projects/{project}/instances/{instance}")
-	databaseAdminDatabasePathTemplate = gax.MustCompilePathTemplate("projects/{project}/instances/{instance}/databases/{database}")
-)
-
-// DatabaseAdminCallOptions contains the retry settings for each method of DatabaseAdminClient.
-type DatabaseAdminCallOptions struct {
-	ListDatabases      []gax.CallOption
-	CreateDatabase     []gax.CallOption
-	GetDatabase        []gax.CallOption
-	UpdateDatabaseDdl  []gax.CallOption
-	DropDatabase       []gax.CallOption
-	GetDatabaseDdl     []gax.CallOption
-	SetIamPolicy       []gax.CallOption
-	GetIamPolicy       []gax.CallOption
-	TestIamPermissions []gax.CallOption
-}
-
-func defaultDatabaseAdminClientOptions() []option.ClientOption {
-	return []option.ClientOption{
-		option.WithEndpoint("spanner.googleapis.com:443"),
-		option.WithScopes(DefaultAuthScopes()...),
-	}
-}
-
-func defaultDatabaseAdminCallOptions() *DatabaseAdminCallOptions {
-	retry := map[[2]string][]gax.CallOption{
-		{"default", "idempotent"}: {
-			gax.WithRetry(func() gax.Retryer {
-				return gax.OnCodes([]codes.Code{
-					codes.DeadlineExceeded,
-					codes.Unavailable,
-				}, gax.Backoff{
-					Initial:    1000 * time.Millisecond,
-					Max:        32000 * time.Millisecond,
-					Multiplier: 1.3,
-				})
-			}),
-		},
-		{"default", "non_idempotent"}: {
-			gax.WithRetry(func() gax.Retryer {
-				return gax.OnCodes([]codes.Code{
-					codes.Unavailable,
-				}, gax.Backoff{
-					Initial:    1000 * time.Millisecond,
-					Max:        32000 * time.Millisecond,
-					Multiplier: 1.3,
-				})
-			}),
-		},
-	}
-	return &DatabaseAdminCallOptions{
-		ListDatabases:      retry[[2]string{"default", "idempotent"}],
-		CreateDatabase:     retry[[2]string{"default", "non_idempotent"}],
-		GetDatabase:        retry[[2]string{"default", "idempotent"}],
-		UpdateDatabaseDdl:  retry[[2]string{"default", "idempotent"}],
-		DropDatabase:       retry[[2]string{"default", "idempotent"}],
-		GetDatabaseDdl:     retry[[2]string{"default", "idempotent"}],
-		SetIamPolicy:       retry[[2]string{"default", "non_idempotent"}],
-		GetIamPolicy:       retry[[2]string{"default", "idempotent"}],
-		TestIamPermissions: retry[[2]string{"default", "non_idempotent"}],
-	}
-}
-
-// DatabaseAdminClient is a client for interacting with Cloud Spanner Database Admin API.
-type DatabaseAdminClient struct {
-	// The connection to the service.
-	conn *grpc.ClientConn
-
-	// The gRPC API client.
-	databaseAdminClient databasepb.DatabaseAdminClient
-
-	// LROClient is used internally to handle longrunning operations.
-	// It is exposed so that its CallOptions can be modified if required.
-	// Users should not Close this client.
-	LROClient *lroauto.OperationsClient
-
-	// The call options for this service.
-	CallOptions *DatabaseAdminCallOptions
-
-	// The metadata to be sent with each request.
-	xGoogHeader []string
-}
-
-// NewDatabaseAdminClient creates a new database admin client.
-//
-// Cloud Spanner Database Admin API
-//
-// The Cloud Spanner Database Admin API can be used to create, drop, and
-// list databases. It also enables updating the schema of pre-existing
-// databases.
-func NewDatabaseAdminClient(ctx context.Context, opts ...option.ClientOption) (*DatabaseAdminClient, error) {
-	conn, err := transport.DialGRPC(ctx, append(defaultDatabaseAdminClientOptions(), opts...)...)
-	if err != nil {
-		return nil, err
-	}
-	c := &DatabaseAdminClient{
-		conn:        conn,
-		CallOptions: defaultDatabaseAdminCallOptions(),
-
-		databaseAdminClient: databasepb.NewDatabaseAdminClient(conn),
-	}
-	c.SetGoogleClientInfo()
-
-	c.LROClient, err = lroauto.NewOperationsClient(ctx, option.WithGRPCConn(conn))
-	if err != nil {
-		// This error "should not happen", since we are just reusing old connection
-		// and never actually need to dial.
-		// If this does happen, we could leak conn. However, we cannot close conn:
-		// If the user invoked the function with option.WithGRPCConn,
-		// we would close a connection that's still in use.
-		// TODO(pongad): investigate error conditions.
-		return nil, err
-	}
-	return c, nil
-}
-
-// Connection returns the client's connection to the API service.
-func (c *DatabaseAdminClient) Connection() *grpc.ClientConn {
-	return c.conn
-}
-
-// Close closes the connection to the API service. The user should invoke this when
-// the client is no longer required.
-func (c *DatabaseAdminClient) Close() error {
-	return c.conn.Close()
-}
-
-// SetGoogleClientInfo sets the name and version of the application in
-// the `x-goog-api-client` header passed on each request. Intended for
-// use by Google-written clients.
-func (c *DatabaseAdminClient) SetGoogleClientInfo(keyval ...string) {
-	kv := append([]string{"gl-go", version.Go()}, keyval...)
-	kv = append(kv, "gapic", version.Repo, "gax", gax.Version, "grpc", grpc.Version)
-	c.xGoogHeader = []string{gax.XGoogHeader(kv...)}
-}
-
-// DatabaseAdminInstancePath returns the path for the instance resource.
-func DatabaseAdminInstancePath(project, instance string) string {
-	path, err := databaseAdminInstancePathTemplate.Render(map[string]string{
-		"project":  project,
-		"instance": instance,
-	})
-	if err != nil {
-		panic(err)
-	}
-	return path
-}
-
-// DatabaseAdminDatabasePath returns the path for the database resource.
-func DatabaseAdminDatabasePath(project, instance, database string) string {
-	path, err := databaseAdminDatabasePathTemplate.Render(map[string]string{
-		"project":  project,
-		"instance": instance,
-		"database": database,
-	})
-	if err != nil {
-		panic(err)
-	}
-	return path
-}
-
-// ListDatabases lists Cloud Spanner databases.
-func (c *DatabaseAdminClient) ListDatabases(ctx context.Context, req *databasepb.ListDatabasesRequest, opts ...gax.CallOption) *DatabaseIterator {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.ListDatabases[0:len(c.CallOptions.ListDatabases):len(c.CallOptions.ListDatabases)], opts...)
-	it := &DatabaseIterator{}
-	it.InternalFetch = func(pageSize int, pageToken string) ([]*databasepb.Database, string, error) {
-		var resp *databasepb.ListDatabasesResponse
-		req.PageToken = pageToken
-		if pageSize > math.MaxInt32 {
-			req.PageSize = math.MaxInt32
-		} else {
-			req.PageSize = int32(pageSize)
-		}
-		err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-			var err error
-			resp, err = c.databaseAdminClient.ListDatabases(ctx, req, settings.GRPC...)
-			return err
-		}, opts...)
-		if err != nil {
-			return nil, "", err
-		}
-		return resp.Databases, resp.NextPageToken, nil
-	}
-	fetch := func(pageSize int, pageToken string) (string, error) {
-		items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
-		if err != nil {
-			return "", err
-		}
-		it.items = append(it.items, items...)
-		return nextPageToken, nil
-	}
-	it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
-	return it
-}
-
-// CreateDatabase creates a new Cloud Spanner database and starts to prepare it for serving.
-// The returned [long-running operation][google.longrunning.Operation] will
-// have a name of the format `<database_name>/operations/<operation_id>` and
-// can be used to track preparation of the database. The
-// [metadata][google.longrunning.Operation.metadata] field type is
-// [CreateDatabaseMetadata][google.spanner.admin.database.v1.CreateDatabaseMetadata]. The
-// [response][google.longrunning.Operation.response] field type is
-// [Database][google.spanner.admin.database.v1.Database], if successful.
-func (c *DatabaseAdminClient) CreateDatabase(ctx context.Context, req *databasepb.CreateDatabaseRequest, opts ...gax.CallOption) (*CreateDatabaseOperation, error) {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.CreateDatabase[0:len(c.CallOptions.CreateDatabase):len(c.CallOptions.CreateDatabase)], opts...)
-	var resp *longrunningpb.Operation
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		resp, err = c.databaseAdminClient.CreateDatabase(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return &CreateDatabaseOperation{
-		lro: longrunning.InternalNewOperation(c.LROClient, resp),
-	}, nil
-}
-
-// GetDatabase gets the state of a Cloud Spanner database.
-func (c *DatabaseAdminClient) GetDatabase(ctx context.Context, req *databasepb.GetDatabaseRequest, opts ...gax.CallOption) (*databasepb.Database, error) {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.GetDatabase[0:len(c.CallOptions.GetDatabase):len(c.CallOptions.GetDatabase)], opts...)
-	var resp *databasepb.Database
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		resp, err = c.databaseAdminClient.GetDatabase(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return resp, nil
-}
-
-// UpdateDatabaseDdl updates the schema of a Cloud Spanner database by
-// creating/altering/dropping tables, columns, indexes, etc. The returned
-// [long-running operation][google.longrunning.Operation] will have a name of
-// the format `<database_name>/operations/<operation_id>` and can be used to
-// track execution of the schema change(s). The
-// [metadata][google.longrunning.Operation.metadata] field type is
-// [UpdateDatabaseDdlMetadata][google.spanner.admin.database.v1.UpdateDatabaseDdlMetadata].  The operation has no response.
-func (c *DatabaseAdminClient) UpdateDatabaseDdl(ctx context.Context, req *databasepb.UpdateDatabaseDdlRequest, opts ...gax.CallOption) (*UpdateDatabaseDdlOperation, error) {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.UpdateDatabaseDdl[0:len(c.CallOptions.UpdateDatabaseDdl):len(c.CallOptions.UpdateDatabaseDdl)], opts...)
-	var resp *longrunningpb.Operation
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		resp, err = c.databaseAdminClient.UpdateDatabaseDdl(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return &UpdateDatabaseDdlOperation{
-		lro: longrunning.InternalNewOperation(c.LROClient, resp),
-	}, nil
-}
-
-// DropDatabase drops (aka deletes) a Cloud Spanner database.
-func (c *DatabaseAdminClient) DropDatabase(ctx context.Context, req *databasepb.DropDatabaseRequest, opts ...gax.CallOption) error {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.DropDatabase[0:len(c.CallOptions.DropDatabase):len(c.CallOptions.DropDatabase)], opts...)
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		_, err = c.databaseAdminClient.DropDatabase(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	return err
-}
-
-// GetDatabaseDdl returns the schema of a Cloud Spanner database as a list of formatted
-// DDL statements. This method does not show pending schema updates, those may
-// be queried using the [Operations][google.longrunning.Operations] API.
-func (c *DatabaseAdminClient) GetDatabaseDdl(ctx context.Context, req *databasepb.GetDatabaseDdlRequest, opts ...gax.CallOption) (*databasepb.GetDatabaseDdlResponse, error) {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.GetDatabaseDdl[0:len(c.CallOptions.GetDatabaseDdl):len(c.CallOptions.GetDatabaseDdl)], opts...)
-	var resp *databasepb.GetDatabaseDdlResponse
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		resp, err = c.databaseAdminClient.GetDatabaseDdl(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return resp, nil
-}
-
-// SetIamPolicy sets the access control policy on a database resource. Replaces any
-// existing policy.
-//
-// Authorization requires `spanner.databases.setIamPolicy` permission on
-// [resource][google.iam.v1.SetIamPolicyRequest.resource].
-func (c *DatabaseAdminClient) SetIamPolicy(ctx context.Context, req *iampb.SetIamPolicyRequest, opts ...gax.CallOption) (*iampb.Policy, error) {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.SetIamPolicy[0:len(c.CallOptions.SetIamPolicy):len(c.CallOptions.SetIamPolicy)], opts...)
-	var resp *iampb.Policy
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		resp, err = c.databaseAdminClient.SetIamPolicy(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return resp, nil
-}
-
-// GetIamPolicy gets the access control policy for a database resource. Returns an empty
-// policy if a database exists but does not have a policy set.
-//
-// Authorization requires `spanner.databases.getIamPolicy` permission on
-// [resource][google.iam.v1.GetIamPolicyRequest.resource].
-func (c *DatabaseAdminClient) GetIamPolicy(ctx context.Context, req *iampb.GetIamPolicyRequest, opts ...gax.CallOption) (*iampb.Policy, error) {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.GetIamPolicy[0:len(c.CallOptions.GetIamPolicy):len(c.CallOptions.GetIamPolicy)], opts...)
-	var resp *iampb.Policy
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		resp, err = c.databaseAdminClient.GetIamPolicy(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return resp, nil
-}
-
-// TestIamPermissions returns permissions that the caller has on the specified database resource.
-//
-// Attempting this RPC on a non-existent Cloud Spanner database will result in
-// a NOT_FOUND error if the user has `spanner.databases.list` permission on
-// the containing Cloud Spanner instance. Otherwise returns an empty set of
-// permissions.
-func (c *DatabaseAdminClient) TestIamPermissions(ctx context.Context, req *iampb.TestIamPermissionsRequest, opts ...gax.CallOption) (*iampb.TestIamPermissionsResponse, error) {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.TestIamPermissions[0:len(c.CallOptions.TestIamPermissions):len(c.CallOptions.TestIamPermissions)], opts...)
-	var resp *iampb.TestIamPermissionsResponse
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		resp, err = c.databaseAdminClient.TestIamPermissions(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return resp, nil
-}
-
-// DatabaseIterator manages a stream of *databasepb.Database.
-type DatabaseIterator struct {
-	items    []*databasepb.Database
-	pageInfo *iterator.PageInfo
-	nextFunc func() error
-
-	// InternalFetch is for use by the Google Cloud Libraries only.
-	// It is not part of the stable interface of this package.
-	//
-	// InternalFetch returns results from a single call to the underlying RPC.
-	// The number of results is no greater than pageSize.
-	// If there are no more results, nextPageToken is empty and err is nil.
-	InternalFetch func(pageSize int, pageToken string) (results []*databasepb.Database, nextPageToken string, err error)
-}
-
-// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
-func (it *DatabaseIterator) PageInfo() *iterator.PageInfo {
-	return it.pageInfo
-}
-
-// Next returns the next result. Its second return value is iterator.Done if there are no more
-// results. Once Next returns Done, all subsequent calls will return Done.
-func (it *DatabaseIterator) Next() (*databasepb.Database, error) {
-	var item *databasepb.Database
-	if err := it.nextFunc(); err != nil {
-		return item, err
-	}
-	item = it.items[0]
-	it.items = it.items[1:]
-	return item, nil
-}
-
-func (it *DatabaseIterator) bufLen() int {
-	return len(it.items)
-}
-
-func (it *DatabaseIterator) takeBuf() interface{} {
-	b := it.items
-	it.items = nil
-	return b
-}
-
-// CreateDatabaseOperation manages a long-running operation from CreateDatabase.
-type CreateDatabaseOperation struct {
-	lro *longrunning.Operation
-}
-
-// CreateDatabaseOperation returns a new CreateDatabaseOperation from a given name.
-// The name must be that of a previously created CreateDatabaseOperation, possibly from a different process.
-func (c *DatabaseAdminClient) CreateDatabaseOperation(name string) *CreateDatabaseOperation {
-	return &CreateDatabaseOperation{
-		lro: longrunning.InternalNewOperation(c.LROClient, &longrunningpb.Operation{Name: name}),
-	}
-}
-
-// Wait blocks until the long-running operation is completed, returning the response and any errors encountered.
-//
-// See documentation of Poll for error-handling information.
-func (op *CreateDatabaseOperation) Wait(ctx context.Context, opts ...gax.CallOption) (*databasepb.Database, error) {
-	var resp databasepb.Database
-	if err := op.lro.Wait(ctx, &resp, opts...); err != nil {
-		return nil, err
-	}
-	return &resp, nil
-}
-
-// Poll fetches the latest state of the long-running operation.
-//
-// Poll also fetches the latest metadata, which can be retrieved by Metadata.
-//
-// If Poll fails, the error is returned and op is unmodified. If Poll succeeds and
-// the operation has completed with failure, the error is returned and op.Done will return true.
-// If Poll succeeds and the operation has completed successfully,
-// op.Done will return true, and the response of the operation is returned.
-// If Poll succeeds and the operation has not completed, the returned response and error are both nil.
-func (op *CreateDatabaseOperation) Poll(ctx context.Context, opts ...gax.CallOption) (*databasepb.Database, error) {
-	var resp databasepb.Database
-	if err := op.lro.Poll(ctx, &resp, opts...); err != nil {
-		return nil, err
-	}
-	if !op.Done() {
-		return nil, nil
-	}
-	return &resp, nil
-}
-
-// Metadata returns metadata associated with the long-running operation.
-// Metadata itself does not contact the server, but Poll does.
-// To get the latest metadata, call this method after a successful call to Poll.
-// If the metadata is not available, the returned metadata and error are both nil.
-func (op *CreateDatabaseOperation) Metadata() (*databasepb.CreateDatabaseMetadata, error) {
-	var meta databasepb.CreateDatabaseMetadata
-	if err := op.lro.Metadata(&meta); err == longrunning.ErrNoMetadata {
-		return nil, nil
-	} else if err != nil {
-		return nil, err
-	}
-	return &meta, nil
-}
-
-// Done reports whether the long-running operation has completed.
-func (op *CreateDatabaseOperation) Done() bool {
-	return op.lro.Done()
-}
-
-// Name returns the name of the long-running operation.
-// The name is assigned by the server and is unique within the service from which the operation is created.
-func (op *CreateDatabaseOperation) Name() string {
-	return op.lro.Name()
-}
-
-// UpdateDatabaseDdlOperation manages a long-running operation from UpdateDatabaseDdl.
-type UpdateDatabaseDdlOperation struct {
-	lro *longrunning.Operation
-}
-
-// UpdateDatabaseDdlOperation returns a new UpdateDatabaseDdlOperation from a given name.
-// The name must be that of a previously created UpdateDatabaseDdlOperation, possibly from a different process.
-func (c *DatabaseAdminClient) UpdateDatabaseDdlOperation(name string) *UpdateDatabaseDdlOperation {
-	return &UpdateDatabaseDdlOperation{
-		lro: longrunning.InternalNewOperation(c.LROClient, &longrunningpb.Operation{Name: name}),
-	}
-}
-
-// Wait blocks until the long-running operation is completed, returning any error encountered.
-//
-// See documentation of Poll for error-handling information.
-func (op *UpdateDatabaseDdlOperation) Wait(ctx context.Context, opts ...gax.CallOption) error {
-	return op.lro.Wait(ctx, nil, opts...)
-}
-
-// Poll fetches the latest state of the long-running operation.
-//
-// Poll also fetches the latest metadata, which can be retrieved by Metadata.
-//
-// If Poll fails, the error is returned and op is unmodified. If Poll succeeds and
-// the operation has completed with failure, the error is returned and op.Done will return true.
-// If Poll succeeds and the operation has completed successfully, op.Done will return true.
-func (op *UpdateDatabaseDdlOperation) Poll(ctx context.Context, opts ...gax.CallOption) error {
-	return op.lro.Poll(ctx, nil, opts...)
-}
-
-// Metadata returns metadata associated with the long-running operation.
-// Metadata itself does not contact the server, but Poll does.
-// To get the latest metadata, call this method after a successful call to Poll.
-// If the metadata is not available, the returned metadata and error are both nil.
-func (op *UpdateDatabaseDdlOperation) Metadata() (*databasepb.UpdateDatabaseDdlMetadata, error) {
-	var meta databasepb.UpdateDatabaseDdlMetadata
-	if err := op.lro.Metadata(&meta); err == longrunning.ErrNoMetadata {
-		return nil, nil
-	} else if err != nil {
-		return nil, err
-	}
-	return &meta, nil
-}
-
-// Done reports whether the long-running operation has completed.
-func (op *UpdateDatabaseDdlOperation) Done() bool {
-	return op.lro.Done()
-}
-
-// Name returns the name of the long-running operation.
-// The name is assigned by the server and is unique within the service from which the operation is created.
-func (op *UpdateDatabaseDdlOperation) Name() string {
-	return op.lro.Name()
-}
diff --git a/vendor/cloud.google.com/go/spanner/admin/database/apiv1/database_admin_client_example_test.go b/vendor/cloud.google.com/go/spanner/admin/database/apiv1/database_admin_client_example_test.go
deleted file mode 100644
index 0769d1193..000000000
--- a/vendor/cloud.google.com/go/spanner/admin/database/apiv1/database_admin_client_example_test.go
+++ /dev/null
@@ -1,204 +0,0 @@
-// Copyright 2017, Google Inc. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// AUTO-GENERATED CODE. DO NOT EDIT.
-
-package database_test
-
-import (
-	"cloud.google.com/go/spanner/admin/database/apiv1"
-	"golang.org/x/net/context"
-	iampb "google.golang.org/genproto/googleapis/iam/v1"
-	databasepb "google.golang.org/genproto/googleapis/spanner/admin/database/v1"
-)
-
-func ExampleNewDatabaseAdminClient() {
-	ctx := context.Background()
-	c, err := database.NewDatabaseAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use client.
-	_ = c
-}
-
-func ExampleDatabaseAdminClient_ListDatabases() {
-	ctx := context.Background()
-	c, err := database.NewDatabaseAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &databasepb.ListDatabasesRequest{
-	// TODO: Fill request struct fields.
-	}
-	it := c.ListDatabases(ctx, req)
-	for {
-		resp, err := it.Next()
-		if err != nil {
-			// TODO: Handle error.
-			break
-		}
-		// TODO: Use resp.
-		_ = resp
-	}
-}
-
-func ExampleDatabaseAdminClient_CreateDatabase() {
-	ctx := context.Background()
-	c, err := database.NewDatabaseAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &databasepb.CreateDatabaseRequest{
-	// TODO: Fill request struct fields.
-	}
-	op, err := c.CreateDatabase(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	resp, err := op.Wait(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use resp.
-	_ = resp
-}
-
-func ExampleDatabaseAdminClient_GetDatabase() {
-	ctx := context.Background()
-	c, err := database.NewDatabaseAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &databasepb.GetDatabaseRequest{
-	// TODO: Fill request struct fields.
-	}
-	resp, err := c.GetDatabase(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use resp.
-	_ = resp
-}
-
-func ExampleDatabaseAdminClient_UpdateDatabaseDdl() {
-	ctx := context.Background()
-	c, err := database.NewDatabaseAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &databasepb.UpdateDatabaseDdlRequest{
-	// TODO: Fill request struct fields.
-	}
-	op, err := c.UpdateDatabaseDdl(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	err = op.Wait(ctx)
-	// TODO: Handle error.
-}
-
-func ExampleDatabaseAdminClient_DropDatabase() {
-	ctx := context.Background()
-	c, err := database.NewDatabaseAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &databasepb.DropDatabaseRequest{
-	// TODO: Fill request struct fields.
-	}
-	err = c.DropDatabase(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-}
-
-func ExampleDatabaseAdminClient_GetDatabaseDdl() {
-	ctx := context.Background()
-	c, err := database.NewDatabaseAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &databasepb.GetDatabaseDdlRequest{
-	// TODO: Fill request struct fields.
-	}
-	resp, err := c.GetDatabaseDdl(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use resp.
-	_ = resp
-}
-
-func ExampleDatabaseAdminClient_SetIamPolicy() {
-	ctx := context.Background()
-	c, err := database.NewDatabaseAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &iampb.SetIamPolicyRequest{
-	// TODO: Fill request struct fields.
-	}
-	resp, err := c.SetIamPolicy(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use resp.
-	_ = resp
-}
-
-func ExampleDatabaseAdminClient_GetIamPolicy() {
-	ctx := context.Background()
-	c, err := database.NewDatabaseAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &iampb.GetIamPolicyRequest{
-	// TODO: Fill request struct fields.
-	}
-	resp, err := c.GetIamPolicy(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use resp.
-	_ = resp
-}
-
-func ExampleDatabaseAdminClient_TestIamPermissions() {
-	ctx := context.Background()
-	c, err := database.NewDatabaseAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &iampb.TestIamPermissionsRequest{
-	// TODO: Fill request struct fields.
-	}
-	resp, err := c.TestIamPermissions(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use resp.
-	_ = resp
-}
diff --git a/vendor/cloud.google.com/go/spanner/admin/database/apiv1/doc.go b/vendor/cloud.google.com/go/spanner/admin/database/apiv1/doc.go
deleted file mode 100644
index 46eaaae73..000000000
--- a/vendor/cloud.google.com/go/spanner/admin/database/apiv1/doc.go
+++ /dev/null
@@ -1,39 +0,0 @@
-// Copyright 2017, Google Inc. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// AUTO-GENERATED CODE. DO NOT EDIT.
-
-// Package database is an experimental, auto-generated package for the
-// database API.
-//
-package database // import "cloud.google.com/go/spanner/admin/database/apiv1"
-
-import (
-	"golang.org/x/net/context"
-	"google.golang.org/grpc/metadata"
-)
-
-func insertXGoog(ctx context.Context, val []string) context.Context {
-	md, _ := metadata.FromOutgoingContext(ctx)
-	md = md.Copy()
-	md["x-goog-api-client"] = val
-	return metadata.NewOutgoingContext(ctx, md)
-}
-
-func DefaultAuthScopes() []string {
-	return []string{
-		"https://www.googleapis.com/auth/cloud-platform",
-		"https://www.googleapis.com/auth/spanner.admin",
-	}
-}
diff --git a/vendor/cloud.google.com/go/spanner/admin/database/apiv1/mock_test.go b/vendor/cloud.google.com/go/spanner/admin/database/apiv1/mock_test.go
deleted file mode 100644
index accd30cb3..000000000
--- a/vendor/cloud.google.com/go/spanner/admin/database/apiv1/mock_test.go
+++ /dev/null
@@ -1,779 +0,0 @@
-// Copyright 2017, Google Inc. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// AUTO-GENERATED CODE. DO NOT EDIT.
-
-package database
-
-import (
-	emptypb "github.com/golang/protobuf/ptypes/empty"
-	iampb "google.golang.org/genproto/googleapis/iam/v1"
-	longrunningpb "google.golang.org/genproto/googleapis/longrunning"
-	databasepb "google.golang.org/genproto/googleapis/spanner/admin/database/v1"
-)
-
-import (
-	"flag"
-	"fmt"
-	"io"
-	"log"
-	"net"
-	"os"
-	"strings"
-	"testing"
-
-	"github.com/golang/protobuf/proto"
-	"github.com/golang/protobuf/ptypes"
-	"golang.org/x/net/context"
-	"google.golang.org/api/option"
-	status "google.golang.org/genproto/googleapis/rpc/status"
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/metadata"
-)
-
-var _ = io.EOF
-var _ = ptypes.MarshalAny
-var _ status.Status
-
-type mockDatabaseAdminServer struct {
-	// Embed for forward compatibility.
-	// Tests will keep working if more methods are added
-	// in the future.
-	databasepb.DatabaseAdminServer
-
-	reqs []proto.Message
-
-	// If set, all calls return this error.
-	err error
-
-	// responses to return if err == nil
-	resps []proto.Message
-}
-
-func (s *mockDatabaseAdminServer) ListDatabases(ctx context.Context, req *databasepb.ListDatabasesRequest) (*databasepb.ListDatabasesResponse, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*databasepb.ListDatabasesResponse), nil
-}
-
-func (s *mockDatabaseAdminServer) CreateDatabase(ctx context.Context, req *databasepb.CreateDatabaseRequest) (*longrunningpb.Operation, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*longrunningpb.Operation), nil
-}
-
-func (s *mockDatabaseAdminServer) GetDatabase(ctx context.Context, req *databasepb.GetDatabaseRequest) (*databasepb.Database, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*databasepb.Database), nil
-}
-
-func (s *mockDatabaseAdminServer) UpdateDatabaseDdl(ctx context.Context, req *databasepb.UpdateDatabaseDdlRequest) (*longrunningpb.Operation, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*longrunningpb.Operation), nil
-}
-
-func (s *mockDatabaseAdminServer) DropDatabase(ctx context.Context, req *databasepb.DropDatabaseRequest) (*emptypb.Empty, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*emptypb.Empty), nil
-}
-
-func (s *mockDatabaseAdminServer) GetDatabaseDdl(ctx context.Context, req *databasepb.GetDatabaseDdlRequest) (*databasepb.GetDatabaseDdlResponse, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*databasepb.GetDatabaseDdlResponse), nil
-}
-
-func (s *mockDatabaseAdminServer) SetIamPolicy(ctx context.Context, req *iampb.SetIamPolicyRequest) (*iampb.Policy, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*iampb.Policy), nil
-}
-
-func (s *mockDatabaseAdminServer) GetIamPolicy(ctx context.Context, req *iampb.GetIamPolicyRequest) (*iampb.Policy, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*iampb.Policy), nil
-}
-
-func (s *mockDatabaseAdminServer) TestIamPermissions(ctx context.Context, req *iampb.TestIamPermissionsRequest) (*iampb.TestIamPermissionsResponse, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*iampb.TestIamPermissionsResponse), nil
-}
-
-// clientOpt is the option tests should use to connect to the test server.
-// It is initialized by TestMain.
-var clientOpt option.ClientOption
-
-var (
-	mockDatabaseAdmin mockDatabaseAdminServer
-)
-
-func TestMain(m *testing.M) {
-	flag.Parse()
-
-	serv := grpc.NewServer()
-	databasepb.RegisterDatabaseAdminServer(serv, &mockDatabaseAdmin)
-
-	lis, err := net.Listen("tcp", "localhost:0")
-	if err != nil {
-		log.Fatal(err)
-	}
-	go serv.Serve(lis)
-
-	conn, err := grpc.Dial(lis.Addr().String(), grpc.WithInsecure())
-	if err != nil {
-		log.Fatal(err)
-	}
-	clientOpt = option.WithGRPCConn(conn)
-
-	os.Exit(m.Run())
-}
-
-func TestDatabaseAdminListDatabases(t *testing.T) {
-	var nextPageToken string = ""
-	var databasesElement *databasepb.Database = &databasepb.Database{}
-	var databases = []*databasepb.Database{databasesElement}
-	var expectedResponse = &databasepb.ListDatabasesResponse{
-		NextPageToken: nextPageToken,
-		Databases:     databases,
-	}
-
-	mockDatabaseAdmin.err = nil
-	mockDatabaseAdmin.reqs = nil
-
-	mockDatabaseAdmin.resps = append(mockDatabaseAdmin.resps[:0], expectedResponse)
-
-	var formattedParent string = DatabaseAdminInstancePath("[PROJECT]", "[INSTANCE]")
-	var request = &databasepb.ListDatabasesRequest{
-		Parent: formattedParent,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.ListDatabases(context.Background(), request).Next()
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockDatabaseAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	want := (interface{})(expectedResponse.Databases[0])
-	got := (interface{})(resp)
-	var ok bool
-
-	switch want := (want).(type) {
-	case proto.Message:
-		ok = proto.Equal(want, got.(proto.Message))
-	default:
-		ok = want == got
-	}
-	if !ok {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestDatabaseAdminListDatabasesError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockDatabaseAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedParent string = DatabaseAdminInstancePath("[PROJECT]", "[INSTANCE]")
-	var request = &databasepb.ListDatabasesRequest{
-		Parent: formattedParent,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.ListDatabases(context.Background(), request).Next()
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
-func TestDatabaseAdminCreateDatabase(t *testing.T) {
-	var name string = "name3373707"
-	var expectedResponse = &databasepb.Database{
-		Name: name,
-	}
-
-	mockDatabaseAdmin.err = nil
-	mockDatabaseAdmin.reqs = nil
-
-	any, err := ptypes.MarshalAny(expectedResponse)
-	if err != nil {
-		t.Fatal(err)
-	}
-	mockDatabaseAdmin.resps = append(mockDatabaseAdmin.resps[:0], &longrunningpb.Operation{
-		Name:   "longrunning-test",
-		Done:   true,
-		Result: &longrunningpb.Operation_Response{Response: any},
-	})
-
-	var formattedParent string = DatabaseAdminInstancePath("[PROJECT]", "[INSTANCE]")
-	var createStatement string = "createStatement552974828"
-	var request = &databasepb.CreateDatabaseRequest{
-		Parent:          formattedParent,
-		CreateStatement: createStatement,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	respLRO, err := c.CreateDatabase(context.Background(), request)
-	if err != nil {
-		t.Fatal(err)
-	}
-	resp, err := respLRO.Wait(context.Background())
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockDatabaseAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	if want, got := expectedResponse, resp; !proto.Equal(want, got) {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestDatabaseAdminCreateDatabaseError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockDatabaseAdmin.err = nil
-	mockDatabaseAdmin.resps = append(mockDatabaseAdmin.resps[:0], &longrunningpb.Operation{
-		Name: "longrunning-test",
-		Done: true,
-		Result: &longrunningpb.Operation_Error{
-			Error: &status.Status{
-				Code:    int32(errCode),
-				Message: "test error",
-			},
-		},
-	})
-
-	var formattedParent string = DatabaseAdminInstancePath("[PROJECT]", "[INSTANCE]")
-	var createStatement string = "createStatement552974828"
-	var request = &databasepb.CreateDatabaseRequest{
-		Parent:          formattedParent,
-		CreateStatement: createStatement,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	respLRO, err := c.CreateDatabase(context.Background(), request)
-	if err != nil {
-		t.Fatal(err)
-	}
-	resp, err := respLRO.Wait(context.Background())
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
-func TestDatabaseAdminGetDatabase(t *testing.T) {
-	var name2 string = "name2-1052831874"
-	var expectedResponse = &databasepb.Database{
-		Name: name2,
-	}
-
-	mockDatabaseAdmin.err = nil
-	mockDatabaseAdmin.reqs = nil
-
-	mockDatabaseAdmin.resps = append(mockDatabaseAdmin.resps[:0], expectedResponse)
-
-	var formattedName string = DatabaseAdminDatabasePath("[PROJECT]", "[INSTANCE]", "[DATABASE]")
-	var request = &databasepb.GetDatabaseRequest{
-		Name: formattedName,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.GetDatabase(context.Background(), request)
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockDatabaseAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	if want, got := expectedResponse, resp; !proto.Equal(want, got) {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestDatabaseAdminGetDatabaseError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockDatabaseAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedName string = DatabaseAdminDatabasePath("[PROJECT]", "[INSTANCE]", "[DATABASE]")
-	var request = &databasepb.GetDatabaseRequest{
-		Name: formattedName,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.GetDatabase(context.Background(), request)
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
-func TestDatabaseAdminUpdateDatabaseDdl(t *testing.T) {
-	var expectedResponse *emptypb.Empty = &emptypb.Empty{}
-
-	mockDatabaseAdmin.err = nil
-	mockDatabaseAdmin.reqs = nil
-
-	any, err := ptypes.MarshalAny(expectedResponse)
-	if err != nil {
-		t.Fatal(err)
-	}
-	mockDatabaseAdmin.resps = append(mockDatabaseAdmin.resps[:0], &longrunningpb.Operation{
-		Name:   "longrunning-test",
-		Done:   true,
-		Result: &longrunningpb.Operation_Response{Response: any},
-	})
-
-	var formattedDatabase string = DatabaseAdminDatabasePath("[PROJECT]", "[INSTANCE]", "[DATABASE]")
-	var statements []string = nil
-	var request = &databasepb.UpdateDatabaseDdlRequest{
-		Database:   formattedDatabase,
-		Statements: statements,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	respLRO, err := c.UpdateDatabaseDdl(context.Background(), request)
-	if err != nil {
-		t.Fatal(err)
-	}
-	err = respLRO.Wait(context.Background())
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockDatabaseAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-}
-
-func TestDatabaseAdminUpdateDatabaseDdlError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockDatabaseAdmin.err = nil
-	mockDatabaseAdmin.resps = append(mockDatabaseAdmin.resps[:0], &longrunningpb.Operation{
-		Name: "longrunning-test",
-		Done: true,
-		Result: &longrunningpb.Operation_Error{
-			Error: &status.Status{
-				Code:    int32(errCode),
-				Message: "test error",
-			},
-		},
-	})
-
-	var formattedDatabase string = DatabaseAdminDatabasePath("[PROJECT]", "[INSTANCE]", "[DATABASE]")
-	var statements []string = nil
-	var request = &databasepb.UpdateDatabaseDdlRequest{
-		Database:   formattedDatabase,
-		Statements: statements,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	respLRO, err := c.UpdateDatabaseDdl(context.Background(), request)
-	if err != nil {
-		t.Fatal(err)
-	}
-	err = respLRO.Wait(context.Background())
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-}
-func TestDatabaseAdminDropDatabase(t *testing.T) {
-	var expectedResponse *emptypb.Empty = &emptypb.Empty{}
-
-	mockDatabaseAdmin.err = nil
-	mockDatabaseAdmin.reqs = nil
-
-	mockDatabaseAdmin.resps = append(mockDatabaseAdmin.resps[:0], expectedResponse)
-
-	var formattedDatabase string = DatabaseAdminDatabasePath("[PROJECT]", "[INSTANCE]", "[DATABASE]")
-	var request = &databasepb.DropDatabaseRequest{
-		Database: formattedDatabase,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	err = c.DropDatabase(context.Background(), request)
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockDatabaseAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-}
-
-func TestDatabaseAdminDropDatabaseError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockDatabaseAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedDatabase string = DatabaseAdminDatabasePath("[PROJECT]", "[INSTANCE]", "[DATABASE]")
-	var request = &databasepb.DropDatabaseRequest{
-		Database: formattedDatabase,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	err = c.DropDatabase(context.Background(), request)
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-}
-func TestDatabaseAdminGetDatabaseDdl(t *testing.T) {
-	var expectedResponse *databasepb.GetDatabaseDdlResponse = &databasepb.GetDatabaseDdlResponse{}
-
-	mockDatabaseAdmin.err = nil
-	mockDatabaseAdmin.reqs = nil
-
-	mockDatabaseAdmin.resps = append(mockDatabaseAdmin.resps[:0], expectedResponse)
-
-	var formattedDatabase string = DatabaseAdminDatabasePath("[PROJECT]", "[INSTANCE]", "[DATABASE]")
-	var request = &databasepb.GetDatabaseDdlRequest{
-		Database: formattedDatabase,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.GetDatabaseDdl(context.Background(), request)
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockDatabaseAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	if want, got := expectedResponse, resp; !proto.Equal(want, got) {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestDatabaseAdminGetDatabaseDdlError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockDatabaseAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedDatabase string = DatabaseAdminDatabasePath("[PROJECT]", "[INSTANCE]", "[DATABASE]")
-	var request = &databasepb.GetDatabaseDdlRequest{
-		Database: formattedDatabase,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.GetDatabaseDdl(context.Background(), request)
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
-func TestDatabaseAdminSetIamPolicy(t *testing.T) {
-	var version int32 = 351608024
-	var etag []byte = []byte("21")
-	var expectedResponse = &iampb.Policy{
-		Version: version,
-		Etag:    etag,
-	}
-
-	mockDatabaseAdmin.err = nil
-	mockDatabaseAdmin.reqs = nil
-
-	mockDatabaseAdmin.resps = append(mockDatabaseAdmin.resps[:0], expectedResponse)
-
-	var formattedResource string = DatabaseAdminDatabasePath("[PROJECT]", "[INSTANCE]", "[DATABASE]")
-	var policy *iampb.Policy = &iampb.Policy{}
-	var request = &iampb.SetIamPolicyRequest{
-		Resource: formattedResource,
-		Policy:   policy,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.SetIamPolicy(context.Background(), request)
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockDatabaseAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	if want, got := expectedResponse, resp; !proto.Equal(want, got) {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestDatabaseAdminSetIamPolicyError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockDatabaseAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedResource string = DatabaseAdminDatabasePath("[PROJECT]", "[INSTANCE]", "[DATABASE]")
-	var policy *iampb.Policy = &iampb.Policy{}
-	var request = &iampb.SetIamPolicyRequest{
-		Resource: formattedResource,
-		Policy:   policy,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.SetIamPolicy(context.Background(), request)
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
-func TestDatabaseAdminGetIamPolicy(t *testing.T) {
-	var version int32 = 351608024
-	var etag []byte = []byte("21")
-	var expectedResponse = &iampb.Policy{
-		Version: version,
-		Etag:    etag,
-	}
-
-	mockDatabaseAdmin.err = nil
-	mockDatabaseAdmin.reqs = nil
-
-	mockDatabaseAdmin.resps = append(mockDatabaseAdmin.resps[:0], expectedResponse)
-
-	var formattedResource string = DatabaseAdminDatabasePath("[PROJECT]", "[INSTANCE]", "[DATABASE]")
-	var request = &iampb.GetIamPolicyRequest{
-		Resource: formattedResource,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.GetIamPolicy(context.Background(), request)
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockDatabaseAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	if want, got := expectedResponse, resp; !proto.Equal(want, got) {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestDatabaseAdminGetIamPolicyError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockDatabaseAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedResource string = DatabaseAdminDatabasePath("[PROJECT]", "[INSTANCE]", "[DATABASE]")
-	var request = &iampb.GetIamPolicyRequest{
-		Resource: formattedResource,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.GetIamPolicy(context.Background(), request)
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
-func TestDatabaseAdminTestIamPermissions(t *testing.T) {
-	var expectedResponse *iampb.TestIamPermissionsResponse = &iampb.TestIamPermissionsResponse{}
-
-	mockDatabaseAdmin.err = nil
-	mockDatabaseAdmin.reqs = nil
-
-	mockDatabaseAdmin.resps = append(mockDatabaseAdmin.resps[:0], expectedResponse)
-
-	var formattedResource string = DatabaseAdminDatabasePath("[PROJECT]", "[INSTANCE]", "[DATABASE]")
-	var permissions []string = nil
-	var request = &iampb.TestIamPermissionsRequest{
-		Resource:    formattedResource,
-		Permissions: permissions,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.TestIamPermissions(context.Background(), request)
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockDatabaseAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	if want, got := expectedResponse, resp; !proto.Equal(want, got) {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestDatabaseAdminTestIamPermissionsError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockDatabaseAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedResource string = DatabaseAdminDatabasePath("[PROJECT]", "[INSTANCE]", "[DATABASE]")
-	var permissions []string = nil
-	var request = &iampb.TestIamPermissionsRequest{
-		Resource:    formattedResource,
-		Permissions: permissions,
-	}
-
-	c, err := NewDatabaseAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.TestIamPermissions(context.Background(), request)
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
diff --git a/vendor/cloud.google.com/go/spanner/admin/instance/apiv1/doc.go b/vendor/cloud.google.com/go/spanner/admin/instance/apiv1/doc.go
deleted file mode 100644
index b0c982123..000000000
--- a/vendor/cloud.google.com/go/spanner/admin/instance/apiv1/doc.go
+++ /dev/null
@@ -1,39 +0,0 @@
-// Copyright 2017, Google Inc. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// AUTO-GENERATED CODE. DO NOT EDIT.
-
-// Package instance is an experimental, auto-generated package for the
-// instance API.
-//
-package instance // import "cloud.google.com/go/spanner/admin/instance/apiv1"
-
-import (
-	"golang.org/x/net/context"
-	"google.golang.org/grpc/metadata"
-)
-
-func insertXGoog(ctx context.Context, val []string) context.Context {
-	md, _ := metadata.FromOutgoingContext(ctx)
-	md = md.Copy()
-	md["x-goog-api-client"] = val
-	return metadata.NewOutgoingContext(ctx, md)
-}
-
-func DefaultAuthScopes() []string {
-	return []string{
-		"https://www.googleapis.com/auth/cloud-platform",
-		"https://www.googleapis.com/auth/spanner.admin",
-	}
-}
diff --git a/vendor/cloud.google.com/go/spanner/admin/instance/apiv1/instance_admin_client.go b/vendor/cloud.google.com/go/spanner/admin/instance/apiv1/instance_admin_client.go
deleted file mode 100644
index 138e813f2..000000000
--- a/vendor/cloud.google.com/go/spanner/admin/instance/apiv1/instance_admin_client.go
+++ /dev/null
@@ -1,742 +0,0 @@
-// Copyright 2017, Google Inc. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// AUTO-GENERATED CODE. DO NOT EDIT.
-
-package instance
-
-import (
-	"math"
-	"time"
-
-	"cloud.google.com/go/internal/version"
-	"cloud.google.com/go/longrunning"
-	lroauto "cloud.google.com/go/longrunning/autogen"
-	gax "github.com/googleapis/gax-go"
-	"golang.org/x/net/context"
-	"google.golang.org/api/iterator"
-	"google.golang.org/api/option"
-	"google.golang.org/api/transport"
-	iampb "google.golang.org/genproto/googleapis/iam/v1"
-	longrunningpb "google.golang.org/genproto/googleapis/longrunning"
-	instancepb "google.golang.org/genproto/googleapis/spanner/admin/instance/v1"
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
-)
-
-var (
-	instanceAdminProjectPathTemplate        = gax.MustCompilePathTemplate("projects/{project}")
-	instanceAdminInstanceConfigPathTemplate = gax.MustCompilePathTemplate("projects/{project}/instanceConfigs/{instance_config}")
-	instanceAdminInstancePathTemplate       = gax.MustCompilePathTemplate("projects/{project}/instances/{instance}")
-)
-
-// InstanceAdminCallOptions contains the retry settings for each method of InstanceAdminClient.
-type InstanceAdminCallOptions struct {
-	ListInstanceConfigs []gax.CallOption
-	GetInstanceConfig   []gax.CallOption
-	ListInstances       []gax.CallOption
-	GetInstance         []gax.CallOption
-	CreateInstance      []gax.CallOption
-	UpdateInstance      []gax.CallOption
-	DeleteInstance      []gax.CallOption
-	SetIamPolicy        []gax.CallOption
-	GetIamPolicy        []gax.CallOption
-	TestIamPermissions  []gax.CallOption
-}
-
-func defaultInstanceAdminClientOptions() []option.ClientOption {
-	return []option.ClientOption{
-		option.WithEndpoint("spanner.googleapis.com:443"),
-		option.WithScopes(DefaultAuthScopes()...),
-	}
-}
-
-func defaultInstanceAdminCallOptions() *InstanceAdminCallOptions {
-	retry := map[[2]string][]gax.CallOption{
-		{"default", "idempotent"}: {
-			gax.WithRetry(func() gax.Retryer {
-				return gax.OnCodes([]codes.Code{
-					codes.DeadlineExceeded,
-					codes.Unavailable,
-				}, gax.Backoff{
-					Initial:    1000 * time.Millisecond,
-					Max:        32000 * time.Millisecond,
-					Multiplier: 1.3,
-				})
-			}),
-		},
-		{"default", "non_idempotent"}: {
-			gax.WithRetry(func() gax.Retryer {
-				return gax.OnCodes([]codes.Code{
-					codes.Unavailable,
-				}, gax.Backoff{
-					Initial:    1000 * time.Millisecond,
-					Max:        32000 * time.Millisecond,
-					Multiplier: 1.3,
-				})
-			}),
-		},
-	}
-	return &InstanceAdminCallOptions{
-		ListInstanceConfigs: retry[[2]string{"default", "idempotent"}],
-		GetInstanceConfig:   retry[[2]string{"default", "idempotent"}],
-		ListInstances:       retry[[2]string{"default", "idempotent"}],
-		GetInstance:         retry[[2]string{"default", "idempotent"}],
-		CreateInstance:      retry[[2]string{"default", "non_idempotent"}],
-		UpdateInstance:      retry[[2]string{"default", "non_idempotent"}],
-		DeleteInstance:      retry[[2]string{"default", "idempotent"}],
-		SetIamPolicy:        retry[[2]string{"default", "non_idempotent"}],
-		GetIamPolicy:        retry[[2]string{"default", "idempotent"}],
-		TestIamPermissions:  retry[[2]string{"default", "non_idempotent"}],
-	}
-}
-
-// InstanceAdminClient is a client for interacting with Cloud Spanner Instance Admin API.
-type InstanceAdminClient struct {
-	// The connection to the service.
-	conn *grpc.ClientConn
-
-	// The gRPC API client.
-	instanceAdminClient instancepb.InstanceAdminClient
-
-	// LROClient is used internally to handle longrunning operations.
-	// It is exposed so that its CallOptions can be modified if required.
-	// Users should not Close this client.
-	LROClient *lroauto.OperationsClient
-
-	// The call options for this service.
-	CallOptions *InstanceAdminCallOptions
-
-	// The metadata to be sent with each request.
-	xGoogHeader []string
-}
-
-// NewInstanceAdminClient creates a new instance admin client.
-//
-// Cloud Spanner Instance Admin API
-//
-// The Cloud Spanner Instance Admin API can be used to create, delete,
-// modify and list instances. Instances are dedicated Cloud Spanner serving
-// and storage resources to be used by Cloud Spanner databases.
-//
-// Each instance has a "configuration", which dictates where the
-// serving resources for the Cloud Spanner instance are located (e.g.,
-// US-central, Europe). Configurations are created by Google based on
-// resource availability.
-//
-// Cloud Spanner billing is based on the instances that exist and their
-// sizes. After an instance exists, there are no additional
-// per-database or per-operation charges for use of the instance
-// (though there may be additional network bandwidth charges).
-// Instances offer isolation: problems with databases in one instance
-// will not affect other instances. However, within an instance
-// databases can affect each other. For example, if one database in an
-// instance receives a lot of requests and consumes most of the
-// instance resources, fewer resources are available for other
-// databases in that instance, and their performance may suffer.
-func NewInstanceAdminClient(ctx context.Context, opts ...option.ClientOption) (*InstanceAdminClient, error) {
-	conn, err := transport.DialGRPC(ctx, append(defaultInstanceAdminClientOptions(), opts...)...)
-	if err != nil {
-		return nil, err
-	}
-	c := &InstanceAdminClient{
-		conn:        conn,
-		CallOptions: defaultInstanceAdminCallOptions(),
-
-		instanceAdminClient: instancepb.NewInstanceAdminClient(conn),
-	}
-	c.SetGoogleClientInfo()
-
-	c.LROClient, err = lroauto.NewOperationsClient(ctx, option.WithGRPCConn(conn))
-	if err != nil {
-		// This error "should not happen", since we are just reusing old connection
-		// and never actually need to dial.
-		// If this does happen, we could leak conn. However, we cannot close conn:
-		// If the user invoked the function with option.WithGRPCConn,
-		// we would close a connection that's still in use.
-		// TODO(pongad): investigate error conditions.
-		return nil, err
-	}
-	return c, nil
-}
-
-// Connection returns the client's connection to the API service.
-func (c *InstanceAdminClient) Connection() *grpc.ClientConn {
-	return c.conn
-}
-
-// Close closes the connection to the API service. The user should invoke this when
-// the client is no longer required.
-func (c *InstanceAdminClient) Close() error {
-	return c.conn.Close()
-}
-
-// SetGoogleClientInfo sets the name and version of the application in
-// the `x-goog-api-client` header passed on each request. Intended for
-// use by Google-written clients.
-func (c *InstanceAdminClient) SetGoogleClientInfo(keyval ...string) {
-	kv := append([]string{"gl-go", version.Go()}, keyval...)
-	kv = append(kv, "gapic", version.Repo, "gax", gax.Version, "grpc", grpc.Version)
-	c.xGoogHeader = []string{gax.XGoogHeader(kv...)}
-}
-
-// InstanceAdminProjectPath returns the path for the project resource.
-func InstanceAdminProjectPath(project string) string {
-	path, err := instanceAdminProjectPathTemplate.Render(map[string]string{
-		"project": project,
-	})
-	if err != nil {
-		panic(err)
-	}
-	return path
-}
-
-// InstanceAdminInstanceConfigPath returns the path for the instance config resource.
-func InstanceAdminInstanceConfigPath(project, instanceConfig string) string {
-	path, err := instanceAdminInstanceConfigPathTemplate.Render(map[string]string{
-		"project":         project,
-		"instance_config": instanceConfig,
-	})
-	if err != nil {
-		panic(err)
-	}
-	return path
-}
-
-// InstanceAdminInstancePath returns the path for the instance resource.
-func InstanceAdminInstancePath(project, instance string) string {
-	path, err := instanceAdminInstancePathTemplate.Render(map[string]string{
-		"project":  project,
-		"instance": instance,
-	})
-	if err != nil {
-		panic(err)
-	}
-	return path
-}
-
-// ListInstanceConfigs lists the supported instance configurations for a given project.
-func (c *InstanceAdminClient) ListInstanceConfigs(ctx context.Context, req *instancepb.ListInstanceConfigsRequest, opts ...gax.CallOption) *InstanceConfigIterator {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.ListInstanceConfigs[0:len(c.CallOptions.ListInstanceConfigs):len(c.CallOptions.ListInstanceConfigs)], opts...)
-	it := &InstanceConfigIterator{}
-	it.InternalFetch = func(pageSize int, pageToken string) ([]*instancepb.InstanceConfig, string, error) {
-		var resp *instancepb.ListInstanceConfigsResponse
-		req.PageToken = pageToken
-		if pageSize > math.MaxInt32 {
-			req.PageSize = math.MaxInt32
-		} else {
-			req.PageSize = int32(pageSize)
-		}
-		err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-			var err error
-			resp, err = c.instanceAdminClient.ListInstanceConfigs(ctx, req, settings.GRPC...)
-			return err
-		}, opts...)
-		if err != nil {
-			return nil, "", err
-		}
-		return resp.InstanceConfigs, resp.NextPageToken, nil
-	}
-	fetch := func(pageSize int, pageToken string) (string, error) {
-		items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
-		if err != nil {
-			return "", err
-		}
-		it.items = append(it.items, items...)
-		return nextPageToken, nil
-	}
-	it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
-	return it
-}
-
-// GetInstanceConfig gets information about a particular instance configuration.
-func (c *InstanceAdminClient) GetInstanceConfig(ctx context.Context, req *instancepb.GetInstanceConfigRequest, opts ...gax.CallOption) (*instancepb.InstanceConfig, error) {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.GetInstanceConfig[0:len(c.CallOptions.GetInstanceConfig):len(c.CallOptions.GetInstanceConfig)], opts...)
-	var resp *instancepb.InstanceConfig
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		resp, err = c.instanceAdminClient.GetInstanceConfig(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return resp, nil
-}
-
-// ListInstances lists all instances in the given project.
-func (c *InstanceAdminClient) ListInstances(ctx context.Context, req *instancepb.ListInstancesRequest, opts ...gax.CallOption) *InstanceIterator {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.ListInstances[0:len(c.CallOptions.ListInstances):len(c.CallOptions.ListInstances)], opts...)
-	it := &InstanceIterator{}
-	it.InternalFetch = func(pageSize int, pageToken string) ([]*instancepb.Instance, string, error) {
-		var resp *instancepb.ListInstancesResponse
-		req.PageToken = pageToken
-		if pageSize > math.MaxInt32 {
-			req.PageSize = math.MaxInt32
-		} else {
-			req.PageSize = int32(pageSize)
-		}
-		err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-			var err error
-			resp, err = c.instanceAdminClient.ListInstances(ctx, req, settings.GRPC...)
-			return err
-		}, opts...)
-		if err != nil {
-			return nil, "", err
-		}
-		return resp.Instances, resp.NextPageToken, nil
-	}
-	fetch := func(pageSize int, pageToken string) (string, error) {
-		items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
-		if err != nil {
-			return "", err
-		}
-		it.items = append(it.items, items...)
-		return nextPageToken, nil
-	}
-	it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
-	return it
-}
-
-// GetInstance gets information about a particular instance.
-func (c *InstanceAdminClient) GetInstance(ctx context.Context, req *instancepb.GetInstanceRequest, opts ...gax.CallOption) (*instancepb.Instance, error) {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.GetInstance[0:len(c.CallOptions.GetInstance):len(c.CallOptions.GetInstance)], opts...)
-	var resp *instancepb.Instance
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		resp, err = c.instanceAdminClient.GetInstance(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return resp, nil
-}
-
-// CreateInstance creates an instance and begins preparing it to begin serving. The
-// returned [long-running operation][google.longrunning.Operation]
-// can be used to track the progress of preparing the new
-// instance. The instance name is assigned by the caller. If the
-// named instance already exists, `CreateInstance` returns
-// `ALREADY_EXISTS`.
-//
-// Immediately upon completion of this request:
-//
-//   * The instance is readable via the API, with all requested attributes
-//     but no allocated resources. Its state is `CREATING`.
-//
-// Until completion of the returned operation:
-//
-//   * Cancelling the operation renders the instance immediately unreadable
-//     via the API.
-//   * The instance can be deleted.
-//   * All other attempts to modify the instance are rejected.
-//
-// Upon completion of the returned operation:
-//
-//   * Billing for all successfully-allocated resources begins (some types
-//     may have lower than the requested levels).
-//   * Databases can be created in the instance.
-//   * The instance's allocated resource levels are readable via the API.
-//   * The instance's state becomes `READY`.
-//
-// The returned [long-running operation][google.longrunning.Operation] will
-// have a name of the format `<instance_name>/operations/<operation_id>` and
-// can be used to track creation of the instance.  The
-// [metadata][google.longrunning.Operation.metadata] field type is
-// [CreateInstanceMetadata][google.spanner.admin.instance.v1.CreateInstanceMetadata].
-// The [response][google.longrunning.Operation.response] field type is
-// [Instance][google.spanner.admin.instance.v1.Instance], if successful.
-func (c *InstanceAdminClient) CreateInstance(ctx context.Context, req *instancepb.CreateInstanceRequest, opts ...gax.CallOption) (*CreateInstanceOperation, error) {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.CreateInstance[0:len(c.CallOptions.CreateInstance):len(c.CallOptions.CreateInstance)], opts...)
-	var resp *longrunningpb.Operation
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		resp, err = c.instanceAdminClient.CreateInstance(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return &CreateInstanceOperation{
-		lro: longrunning.InternalNewOperation(c.LROClient, resp),
-	}, nil
-}
-
-// UpdateInstance updates an instance, and begins allocating or releasing resources
-// as requested. The returned [long-running
-// operation][google.longrunning.Operation] can be used to track the
-// progress of updating the instance. If the named instance does not
-// exist, returns `NOT_FOUND`.
-//
-// Immediately upon completion of this request:
-//
-//   * For resource types for which a decrease in the instance's allocation
-//     has been requested, billing is based on the newly-requested level.
-//
-// Until completion of the returned operation:
-//
-//   * Cancelling the operation sets its metadata's
-//     [cancel_time][google.spanner.admin.instance.v1.UpdateInstanceMetadata.cancel_time], and begins
-//     restoring resources to their pre-request values. The operation
-//     is guaranteed to succeed at undoing all resource changes,
-//     after which point it terminates with a `CANCELLED` status.
-//   * All other attempts to modify the instance are rejected.
-//   * Reading the instance via the API continues to give the pre-request
-//     resource levels.
-//
-// Upon completion of the returned operation:
-//
-//   * Billing begins for all successfully-allocated resources (some types
-//     may have lower than the requested levels).
-//   * All newly-reserved resources are available for serving the instance's
-//     tables.
-//   * The instance's new resource levels are readable via the API.
-//
-// The returned [long-running operation][google.longrunning.Operation] will
-// have a name of the format `<instance_name>/operations/<operation_id>` and
-// can be used to track the instance modification.  The
-// [metadata][google.longrunning.Operation.metadata] field type is
-// [UpdateInstanceMetadata][google.spanner.admin.instance.v1.UpdateInstanceMetadata].
-// The [response][google.longrunning.Operation.response] field type is
-// [Instance][google.spanner.admin.instance.v1.Instance], if successful.
-//
-// Authorization requires `spanner.instances.update` permission on
-// resource [name][google.spanner.admin.instance.v1.Instance.name].
-func (c *InstanceAdminClient) UpdateInstance(ctx context.Context, req *instancepb.UpdateInstanceRequest, opts ...gax.CallOption) (*UpdateInstanceOperation, error) {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.UpdateInstance[0:len(c.CallOptions.UpdateInstance):len(c.CallOptions.UpdateInstance)], opts...)
-	var resp *longrunningpb.Operation
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		resp, err = c.instanceAdminClient.UpdateInstance(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return &UpdateInstanceOperation{
-		lro: longrunning.InternalNewOperation(c.LROClient, resp),
-	}, nil
-}
-
-// DeleteInstance deletes an instance.
-//
-// Immediately upon completion of the request:
-//
-//   * Billing ceases for all of the instance's reserved resources.
-//
-// Soon afterward:
-//
-//   * The instance and *all of its databases* immediately and
-//     irrevocably disappear from the API. All data in the databases
-//     is permanently deleted.
-func (c *InstanceAdminClient) DeleteInstance(ctx context.Context, req *instancepb.DeleteInstanceRequest, opts ...gax.CallOption) error {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.DeleteInstance[0:len(c.CallOptions.DeleteInstance):len(c.CallOptions.DeleteInstance)], opts...)
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		_, err = c.instanceAdminClient.DeleteInstance(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	return err
-}
-
-// SetIamPolicy sets the access control policy on an instance resource. Replaces any
-// existing policy.
-//
-// Authorization requires `spanner.instances.setIamPolicy` on
-// [resource][google.iam.v1.SetIamPolicyRequest.resource].
-func (c *InstanceAdminClient) SetIamPolicy(ctx context.Context, req *iampb.SetIamPolicyRequest, opts ...gax.CallOption) (*iampb.Policy, error) {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.SetIamPolicy[0:len(c.CallOptions.SetIamPolicy):len(c.CallOptions.SetIamPolicy)], opts...)
-	var resp *iampb.Policy
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		resp, err = c.instanceAdminClient.SetIamPolicy(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return resp, nil
-}
-
-// GetIamPolicy gets the access control policy for an instance resource. Returns an empty
-// policy if an instance exists but does not have a policy set.
-//
-// Authorization requires `spanner.instances.getIamPolicy` on
-// [resource][google.iam.v1.GetIamPolicyRequest.resource].
-func (c *InstanceAdminClient) GetIamPolicy(ctx context.Context, req *iampb.GetIamPolicyRequest, opts ...gax.CallOption) (*iampb.Policy, error) {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.GetIamPolicy[0:len(c.CallOptions.GetIamPolicy):len(c.CallOptions.GetIamPolicy)], opts...)
-	var resp *iampb.Policy
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		resp, err = c.instanceAdminClient.GetIamPolicy(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return resp, nil
-}
-
-// TestIamPermissions returns permissions that the caller has on the specified instance resource.
-//
-// Attempting this RPC on a non-existent Cloud Spanner instance resource will
-// result in a NOT_FOUND error if the user has `spanner.instances.list`
-// permission on the containing Google Cloud Project. Otherwise returns an
-// empty set of permissions.
-func (c *InstanceAdminClient) TestIamPermissions(ctx context.Context, req *iampb.TestIamPermissionsRequest, opts ...gax.CallOption) (*iampb.TestIamPermissionsResponse, error) {
-	ctx = insertXGoog(ctx, c.xGoogHeader)
-	opts = append(c.CallOptions.TestIamPermissions[0:len(c.CallOptions.TestIamPermissions):len(c.CallOptions.TestIamPermissions)], opts...)
-	var resp *iampb.TestIamPermissionsResponse
-	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
-		var err error
-		resp, err = c.instanceAdminClient.TestIamPermissions(ctx, req, settings.GRPC...)
-		return err
-	}, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return resp, nil
-}
-
-// InstanceConfigIterator manages a stream of *instancepb.InstanceConfig.
-type InstanceConfigIterator struct {
-	items    []*instancepb.InstanceConfig
-	pageInfo *iterator.PageInfo
-	nextFunc func() error
-
-	// InternalFetch is for use by the Google Cloud Libraries only.
-	// It is not part of the stable interface of this package.
-	//
-	// InternalFetch returns results from a single call to the underlying RPC.
-	// The number of results is no greater than pageSize.
-	// If there are no more results, nextPageToken is empty and err is nil.
-	InternalFetch func(pageSize int, pageToken string) (results []*instancepb.InstanceConfig, nextPageToken string, err error)
-}
-
-// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
-func (it *InstanceConfigIterator) PageInfo() *iterator.PageInfo {
-	return it.pageInfo
-}
-
-// Next returns the next result. Its second return value is iterator.Done if there are no more
-// results. Once Next returns Done, all subsequent calls will return Done.
-func (it *InstanceConfigIterator) Next() (*instancepb.InstanceConfig, error) {
-	var item *instancepb.InstanceConfig
-	if err := it.nextFunc(); err != nil {
-		return item, err
-	}
-	item = it.items[0]
-	it.items = it.items[1:]
-	return item, nil
-}
-
-func (it *InstanceConfigIterator) bufLen() int {
-	return len(it.items)
-}
-
-func (it *InstanceConfigIterator) takeBuf() interface{} {
-	b := it.items
-	it.items = nil
-	return b
-}
-
-// InstanceIterator manages a stream of *instancepb.Instance.
-type InstanceIterator struct {
-	items    []*instancepb.Instance
-	pageInfo *iterator.PageInfo
-	nextFunc func() error
-
-	// InternalFetch is for use by the Google Cloud Libraries only.
-	// It is not part of the stable interface of this package.
-	//
-	// InternalFetch returns results from a single call to the underlying RPC.
-	// The number of results is no greater than pageSize.
-	// If there are no more results, nextPageToken is empty and err is nil.
-	InternalFetch func(pageSize int, pageToken string) (results []*instancepb.Instance, nextPageToken string, err error)
-}
-
-// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
-func (it *InstanceIterator) PageInfo() *iterator.PageInfo {
-	return it.pageInfo
-}
-
-// Next returns the next result. Its second return value is iterator.Done if there are no more
-// results. Once Next returns Done, all subsequent calls will return Done.
-func (it *InstanceIterator) Next() (*instancepb.Instance, error) {
-	var item *instancepb.Instance
-	if err := it.nextFunc(); err != nil {
-		return item, err
-	}
-	item = it.items[0]
-	it.items = it.items[1:]
-	return item, nil
-}
-
-func (it *InstanceIterator) bufLen() int {
-	return len(it.items)
-}
-
-func (it *InstanceIterator) takeBuf() interface{} {
-	b := it.items
-	it.items = nil
-	return b
-}
-
-// CreateInstanceOperation manages a long-running operation from CreateInstance.
-type CreateInstanceOperation struct {
-	lro *longrunning.Operation
-}
-
-// CreateInstanceOperation returns a new CreateInstanceOperation from a given name.
-// The name must be that of a previously created CreateInstanceOperation, possibly from a different process.
-func (c *InstanceAdminClient) CreateInstanceOperation(name string) *CreateInstanceOperation {
-	return &CreateInstanceOperation{
-		lro: longrunning.InternalNewOperation(c.LROClient, &longrunningpb.Operation{Name: name}),
-	}
-}
-
-// Wait blocks until the long-running operation is completed, returning the response and any errors encountered.
-//
-// See documentation of Poll for error-handling information.
-func (op *CreateInstanceOperation) Wait(ctx context.Context, opts ...gax.CallOption) (*instancepb.Instance, error) {
-	var resp instancepb.Instance
-	if err := op.lro.Wait(ctx, &resp, opts...); err != nil {
-		return nil, err
-	}
-	return &resp, nil
-}
-
-// Poll fetches the latest state of the long-running operation.
-//
-// Poll also fetches the latest metadata, which can be retrieved by Metadata.
-//
-// If Poll fails, the error is returned and op is unmodified. If Poll succeeds and
-// the operation has completed with failure, the error is returned and op.Done will return true.
-// If Poll succeeds and the operation has completed successfully,
-// op.Done will return true, and the response of the operation is returned.
-// If Poll succeeds and the operation has not completed, the returned response and error are both nil.
-func (op *CreateInstanceOperation) Poll(ctx context.Context, opts ...gax.CallOption) (*instancepb.Instance, error) {
-	var resp instancepb.Instance
-	if err := op.lro.Poll(ctx, &resp, opts...); err != nil {
-		return nil, err
-	}
-	if !op.Done() {
-		return nil, nil
-	}
-	return &resp, nil
-}
-
-// Metadata returns metadata associated with the long-running operation.
-// Metadata itself does not contact the server, but Poll does.
-// To get the latest metadata, call this method after a successful call to Poll.
-// If the metadata is not available, the returned metadata and error are both nil.
-func (op *CreateInstanceOperation) Metadata() (*instancepb.CreateInstanceMetadata, error) {
-	var meta instancepb.CreateInstanceMetadata
-	if err := op.lro.Metadata(&meta); err == longrunning.ErrNoMetadata {
-		return nil, nil
-	} else if err != nil {
-		return nil, err
-	}
-	return &meta, nil
-}
-
-// Done reports whether the long-running operation has completed.
-func (op *CreateInstanceOperation) Done() bool {
-	return op.lro.Done()
-}
-
-// Name returns the name of the long-running operation.
-// The name is assigned by the server and is unique within the service from which the operation is created.
-func (op *CreateInstanceOperation) Name() string {
-	return op.lro.Name()
-}
-
-// UpdateInstanceOperation manages a long-running operation from UpdateInstance.
-type UpdateInstanceOperation struct {
-	lro *longrunning.Operation
-}
-
-// UpdateInstanceOperation returns a new UpdateInstanceOperation from a given name.
-// The name must be that of a previously created UpdateInstanceOperation, possibly from a different process.
-func (c *InstanceAdminClient) UpdateInstanceOperation(name string) *UpdateInstanceOperation {
-	return &UpdateInstanceOperation{
-		lro: longrunning.InternalNewOperation(c.LROClient, &longrunningpb.Operation{Name: name}),
-	}
-}
-
-// Wait blocks until the long-running operation is completed, returning the response and any errors encountered.
-//
-// See documentation of Poll for error-handling information.
-func (op *UpdateInstanceOperation) Wait(ctx context.Context, opts ...gax.CallOption) (*instancepb.Instance, error) {
-	var resp instancepb.Instance
-	if err := op.lro.Wait(ctx, &resp, opts...); err != nil {
-		return nil, err
-	}
-	return &resp, nil
-}
-
-// Poll fetches the latest state of the long-running operation.
-//
-// Poll also fetches the latest metadata, which can be retrieved by Metadata.
-//
-// If Poll fails, the error is returned and op is unmodified. If Poll succeeds and
-// the operation has completed with failure, the error is returned and op.Done will return true.
-// If Poll succeeds and the operation has completed successfully,
-// op.Done will return true, and the response of the operation is returned.
-// If Poll succeeds and the operation has not completed, the returned response and error are both nil.
-func (op *UpdateInstanceOperation) Poll(ctx context.Context, opts ...gax.CallOption) (*instancepb.Instance, error) {
-	var resp instancepb.Instance
-	if err := op.lro.Poll(ctx, &resp, opts...); err != nil {
-		return nil, err
-	}
-	if !op.Done() {
-		return nil, nil
-	}
-	return &resp, nil
-}
-
-// Metadata returns metadata associated with the long-running operation.
-// Metadata itself does not contact the server, but Poll does.
-// To get the latest metadata, call this method after a successful call to Poll.
-// If the metadata is not available, the returned metadata and error are both nil.
-func (op *UpdateInstanceOperation) Metadata() (*instancepb.UpdateInstanceMetadata, error) {
-	var meta instancepb.UpdateInstanceMetadata
-	if err := op.lro.Metadata(&meta); err == longrunning.ErrNoMetadata {
-		return nil, nil
-	} else if err != nil {
-		return nil, err
-	}
-	return &meta, nil
-}
-
-// Done reports whether the long-running operation has completed.
-func (op *UpdateInstanceOperation) Done() bool {
-	return op.lro.Done()
-}
-
-// Name returns the name of the long-running operation.
-// The name is assigned by the server and is unique within the service from which the operation is created.
-func (op *UpdateInstanceOperation) Name() string {
-	return op.lro.Name()
-}
diff --git a/vendor/cloud.google.com/go/spanner/admin/instance/apiv1/instance_admin_client_example_test.go b/vendor/cloud.google.com/go/spanner/admin/instance/apiv1/instance_admin_client_example_test.go
deleted file mode 100644
index ee807fdbc..000000000
--- a/vendor/cloud.google.com/go/spanner/admin/instance/apiv1/instance_admin_client_example_test.go
+++ /dev/null
@@ -1,230 +0,0 @@
-// Copyright 2017, Google Inc. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// AUTO-GENERATED CODE. DO NOT EDIT.
-
-package instance_test
-
-import (
-	"cloud.google.com/go/spanner/admin/instance/apiv1"
-	"golang.org/x/net/context"
-	iampb "google.golang.org/genproto/googleapis/iam/v1"
-	instancepb "google.golang.org/genproto/googleapis/spanner/admin/instance/v1"
-)
-
-func ExampleNewInstanceAdminClient() {
-	ctx := context.Background()
-	c, err := instance.NewInstanceAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use client.
-	_ = c
-}
-
-func ExampleInstanceAdminClient_ListInstanceConfigs() {
-	ctx := context.Background()
-	c, err := instance.NewInstanceAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &instancepb.ListInstanceConfigsRequest{
-	// TODO: Fill request struct fields.
-	}
-	it := c.ListInstanceConfigs(ctx, req)
-	for {
-		resp, err := it.Next()
-		if err != nil {
-			// TODO: Handle error.
-			break
-		}
-		// TODO: Use resp.
-		_ = resp
-	}
-}
-
-func ExampleInstanceAdminClient_GetInstanceConfig() {
-	ctx := context.Background()
-	c, err := instance.NewInstanceAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &instancepb.GetInstanceConfigRequest{
-	// TODO: Fill request struct fields.
-	}
-	resp, err := c.GetInstanceConfig(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use resp.
-	_ = resp
-}
-
-func ExampleInstanceAdminClient_ListInstances() {
-	ctx := context.Background()
-	c, err := instance.NewInstanceAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &instancepb.ListInstancesRequest{
-	// TODO: Fill request struct fields.
-	}
-	it := c.ListInstances(ctx, req)
-	for {
-		resp, err := it.Next()
-		if err != nil {
-			// TODO: Handle error.
-			break
-		}
-		// TODO: Use resp.
-		_ = resp
-	}
-}
-
-func ExampleInstanceAdminClient_GetInstance() {
-	ctx := context.Background()
-	c, err := instance.NewInstanceAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &instancepb.GetInstanceRequest{
-	// TODO: Fill request struct fields.
-	}
-	resp, err := c.GetInstance(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use resp.
-	_ = resp
-}
-
-func ExampleInstanceAdminClient_CreateInstance() {
-	ctx := context.Background()
-	c, err := instance.NewInstanceAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &instancepb.CreateInstanceRequest{
-	// TODO: Fill request struct fields.
-	}
-	op, err := c.CreateInstance(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	resp, err := op.Wait(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use resp.
-	_ = resp
-}
-
-func ExampleInstanceAdminClient_UpdateInstance() {
-	ctx := context.Background()
-	c, err := instance.NewInstanceAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &instancepb.UpdateInstanceRequest{
-	// TODO: Fill request struct fields.
-	}
-	op, err := c.UpdateInstance(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	resp, err := op.Wait(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use resp.
-	_ = resp
-}
-
-func ExampleInstanceAdminClient_DeleteInstance() {
-	ctx := context.Background()
-	c, err := instance.NewInstanceAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &instancepb.DeleteInstanceRequest{
-	// TODO: Fill request struct fields.
-	}
-	err = c.DeleteInstance(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-}
-
-func ExampleInstanceAdminClient_SetIamPolicy() {
-	ctx := context.Background()
-	c, err := instance.NewInstanceAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &iampb.SetIamPolicyRequest{
-	// TODO: Fill request struct fields.
-	}
-	resp, err := c.SetIamPolicy(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use resp.
-	_ = resp
-}
-
-func ExampleInstanceAdminClient_GetIamPolicy() {
-	ctx := context.Background()
-	c, err := instance.NewInstanceAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &iampb.GetIamPolicyRequest{
-	// TODO: Fill request struct fields.
-	}
-	resp, err := c.GetIamPolicy(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use resp.
-	_ = resp
-}
-
-func ExampleInstanceAdminClient_TestIamPermissions() {
-	ctx := context.Background()
-	c, err := instance.NewInstanceAdminClient(ctx)
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	req := &iampb.TestIamPermissionsRequest{
-	// TODO: Fill request struct fields.
-	}
-	resp, err := c.TestIamPermissions(ctx, req)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	// TODO: Use resp.
-	_ = resp
-}
diff --git a/vendor/cloud.google.com/go/spanner/admin/instance/apiv1/mock_test.go b/vendor/cloud.google.com/go/spanner/admin/instance/apiv1/mock_test.go
deleted file mode 100644
index 8728d0b25..000000000
--- a/vendor/cloud.google.com/go/spanner/admin/instance/apiv1/mock_test.go
+++ /dev/null
@@ -1,896 +0,0 @@
-// Copyright 2017, Google Inc. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// AUTO-GENERATED CODE. DO NOT EDIT.
-
-package instance
-
-import (
-	emptypb "github.com/golang/protobuf/ptypes/empty"
-	iampb "google.golang.org/genproto/googleapis/iam/v1"
-	longrunningpb "google.golang.org/genproto/googleapis/longrunning"
-	instancepb "google.golang.org/genproto/googleapis/spanner/admin/instance/v1"
-	field_maskpb "google.golang.org/genproto/protobuf/field_mask"
-)
-
-import (
-	"flag"
-	"fmt"
-	"io"
-	"log"
-	"net"
-	"os"
-	"strings"
-	"testing"
-
-	"github.com/golang/protobuf/proto"
-	"github.com/golang/protobuf/ptypes"
-	"golang.org/x/net/context"
-	"google.golang.org/api/option"
-	status "google.golang.org/genproto/googleapis/rpc/status"
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/metadata"
-)
-
-var _ = io.EOF
-var _ = ptypes.MarshalAny
-var _ status.Status
-
-type mockInstanceAdminServer struct {
-	// Embed for forward compatibility.
-	// Tests will keep working if more methods are added
-	// in the future.
-	instancepb.InstanceAdminServer
-
-	reqs []proto.Message
-
-	// If set, all calls return this error.
-	err error
-
-	// responses to return if err == nil
-	resps []proto.Message
-}
-
-func (s *mockInstanceAdminServer) ListInstanceConfigs(ctx context.Context, req *instancepb.ListInstanceConfigsRequest) (*instancepb.ListInstanceConfigsResponse, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*instancepb.ListInstanceConfigsResponse), nil
-}
-
-func (s *mockInstanceAdminServer) GetInstanceConfig(ctx context.Context, req *instancepb.GetInstanceConfigRequest) (*instancepb.InstanceConfig, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*instancepb.InstanceConfig), nil
-}
-
-func (s *mockInstanceAdminServer) ListInstances(ctx context.Context, req *instancepb.ListInstancesRequest) (*instancepb.ListInstancesResponse, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*instancepb.ListInstancesResponse), nil
-}
-
-func (s *mockInstanceAdminServer) GetInstance(ctx context.Context, req *instancepb.GetInstanceRequest) (*instancepb.Instance, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*instancepb.Instance), nil
-}
-
-func (s *mockInstanceAdminServer) CreateInstance(ctx context.Context, req *instancepb.CreateInstanceRequest) (*longrunningpb.Operation, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*longrunningpb.Operation), nil
-}
-
-func (s *mockInstanceAdminServer) UpdateInstance(ctx context.Context, req *instancepb.UpdateInstanceRequest) (*longrunningpb.Operation, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*longrunningpb.Operation), nil
-}
-
-func (s *mockInstanceAdminServer) DeleteInstance(ctx context.Context, req *instancepb.DeleteInstanceRequest) (*emptypb.Empty, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*emptypb.Empty), nil
-}
-
-func (s *mockInstanceAdminServer) SetIamPolicy(ctx context.Context, req *iampb.SetIamPolicyRequest) (*iampb.Policy, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*iampb.Policy), nil
-}
-
-func (s *mockInstanceAdminServer) GetIamPolicy(ctx context.Context, req *iampb.GetIamPolicyRequest) (*iampb.Policy, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*iampb.Policy), nil
-}
-
-func (s *mockInstanceAdminServer) TestIamPermissions(ctx context.Context, req *iampb.TestIamPermissionsRequest) (*iampb.TestIamPermissionsResponse, error) {
-	md, _ := metadata.FromIncomingContext(ctx)
-	if xg := md["x-goog-api-client"]; len(xg) == 0 || !strings.Contains(xg[0], "gl-go/") {
-		return nil, fmt.Errorf("x-goog-api-client = %v, expected gl-go key", xg)
-	}
-	s.reqs = append(s.reqs, req)
-	if s.err != nil {
-		return nil, s.err
-	}
-	return s.resps[0].(*iampb.TestIamPermissionsResponse), nil
-}
-
-// clientOpt is the option tests should use to connect to the test server.
-// It is initialized by TestMain.
-var clientOpt option.ClientOption
-
-var (
-	mockInstanceAdmin mockInstanceAdminServer
-)
-
-func TestMain(m *testing.M) {
-	flag.Parse()
-
-	serv := grpc.NewServer()
-	instancepb.RegisterInstanceAdminServer(serv, &mockInstanceAdmin)
-
-	lis, err := net.Listen("tcp", "localhost:0")
-	if err != nil {
-		log.Fatal(err)
-	}
-	go serv.Serve(lis)
-
-	conn, err := grpc.Dial(lis.Addr().String(), grpc.WithInsecure())
-	if err != nil {
-		log.Fatal(err)
-	}
-	clientOpt = option.WithGRPCConn(conn)
-
-	os.Exit(m.Run())
-}
-
-func TestInstanceAdminListInstanceConfigs(t *testing.T) {
-	var nextPageToken string = ""
-	var instanceConfigsElement *instancepb.InstanceConfig = &instancepb.InstanceConfig{}
-	var instanceConfigs = []*instancepb.InstanceConfig{instanceConfigsElement}
-	var expectedResponse = &instancepb.ListInstanceConfigsResponse{
-		NextPageToken:   nextPageToken,
-		InstanceConfigs: instanceConfigs,
-	}
-
-	mockInstanceAdmin.err = nil
-	mockInstanceAdmin.reqs = nil
-
-	mockInstanceAdmin.resps = append(mockInstanceAdmin.resps[:0], expectedResponse)
-
-	var formattedParent string = InstanceAdminProjectPath("[PROJECT]")
-	var request = &instancepb.ListInstanceConfigsRequest{
-		Parent: formattedParent,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.ListInstanceConfigs(context.Background(), request).Next()
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockInstanceAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	want := (interface{})(expectedResponse.InstanceConfigs[0])
-	got := (interface{})(resp)
-	var ok bool
-
-	switch want := (want).(type) {
-	case proto.Message:
-		ok = proto.Equal(want, got.(proto.Message))
-	default:
-		ok = want == got
-	}
-	if !ok {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestInstanceAdminListInstanceConfigsError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockInstanceAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedParent string = InstanceAdminProjectPath("[PROJECT]")
-	var request = &instancepb.ListInstanceConfigsRequest{
-		Parent: formattedParent,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.ListInstanceConfigs(context.Background(), request).Next()
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
-func TestInstanceAdminGetInstanceConfig(t *testing.T) {
-	var name2 string = "name2-1052831874"
-	var displayName string = "displayName1615086568"
-	var expectedResponse = &instancepb.InstanceConfig{
-		Name:        name2,
-		DisplayName: displayName,
-	}
-
-	mockInstanceAdmin.err = nil
-	mockInstanceAdmin.reqs = nil
-
-	mockInstanceAdmin.resps = append(mockInstanceAdmin.resps[:0], expectedResponse)
-
-	var formattedName string = InstanceAdminInstanceConfigPath("[PROJECT]", "[INSTANCE_CONFIG]")
-	var request = &instancepb.GetInstanceConfigRequest{
-		Name: formattedName,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.GetInstanceConfig(context.Background(), request)
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockInstanceAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	if want, got := expectedResponse, resp; !proto.Equal(want, got) {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestInstanceAdminGetInstanceConfigError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockInstanceAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedName string = InstanceAdminInstanceConfigPath("[PROJECT]", "[INSTANCE_CONFIG]")
-	var request = &instancepb.GetInstanceConfigRequest{
-		Name: formattedName,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.GetInstanceConfig(context.Background(), request)
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
-func TestInstanceAdminListInstances(t *testing.T) {
-	var nextPageToken string = ""
-	var instancesElement *instancepb.Instance = &instancepb.Instance{}
-	var instances = []*instancepb.Instance{instancesElement}
-	var expectedResponse = &instancepb.ListInstancesResponse{
-		NextPageToken: nextPageToken,
-		Instances:     instances,
-	}
-
-	mockInstanceAdmin.err = nil
-	mockInstanceAdmin.reqs = nil
-
-	mockInstanceAdmin.resps = append(mockInstanceAdmin.resps[:0], expectedResponse)
-
-	var formattedParent string = InstanceAdminProjectPath("[PROJECT]")
-	var request = &instancepb.ListInstancesRequest{
-		Parent: formattedParent,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.ListInstances(context.Background(), request).Next()
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockInstanceAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	want := (interface{})(expectedResponse.Instances[0])
-	got := (interface{})(resp)
-	var ok bool
-
-	switch want := (want).(type) {
-	case proto.Message:
-		ok = proto.Equal(want, got.(proto.Message))
-	default:
-		ok = want == got
-	}
-	if !ok {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestInstanceAdminListInstancesError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockInstanceAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedParent string = InstanceAdminProjectPath("[PROJECT]")
-	var request = &instancepb.ListInstancesRequest{
-		Parent: formattedParent,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.ListInstances(context.Background(), request).Next()
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
-func TestInstanceAdminGetInstance(t *testing.T) {
-	var name2 string = "name2-1052831874"
-	var config string = "config-1354792126"
-	var displayName string = "displayName1615086568"
-	var nodeCount int32 = 1539922066
-	var expectedResponse = &instancepb.Instance{
-		Name:        name2,
-		Config:      config,
-		DisplayName: displayName,
-		NodeCount:   nodeCount,
-	}
-
-	mockInstanceAdmin.err = nil
-	mockInstanceAdmin.reqs = nil
-
-	mockInstanceAdmin.resps = append(mockInstanceAdmin.resps[:0], expectedResponse)
-
-	var formattedName string = InstanceAdminInstancePath("[PROJECT]", "[INSTANCE]")
-	var request = &instancepb.GetInstanceRequest{
-		Name: formattedName,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.GetInstance(context.Background(), request)
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockInstanceAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	if want, got := expectedResponse, resp; !proto.Equal(want, got) {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestInstanceAdminGetInstanceError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockInstanceAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedName string = InstanceAdminInstancePath("[PROJECT]", "[INSTANCE]")
-	var request = &instancepb.GetInstanceRequest{
-		Name: formattedName,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.GetInstance(context.Background(), request)
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
-func TestInstanceAdminCreateInstance(t *testing.T) {
-	var name string = "name3373707"
-	var config string = "config-1354792126"
-	var displayName string = "displayName1615086568"
-	var nodeCount int32 = 1539922066
-	var expectedResponse = &instancepb.Instance{
-		Name:        name,
-		Config:      config,
-		DisplayName: displayName,
-		NodeCount:   nodeCount,
-	}
-
-	mockInstanceAdmin.err = nil
-	mockInstanceAdmin.reqs = nil
-
-	any, err := ptypes.MarshalAny(expectedResponse)
-	if err != nil {
-		t.Fatal(err)
-	}
-	mockInstanceAdmin.resps = append(mockInstanceAdmin.resps[:0], &longrunningpb.Operation{
-		Name:   "longrunning-test",
-		Done:   true,
-		Result: &longrunningpb.Operation_Response{Response: any},
-	})
-
-	var formattedParent string = InstanceAdminProjectPath("[PROJECT]")
-	var instanceId string = "instanceId-2101995259"
-	var instance *instancepb.Instance = &instancepb.Instance{}
-	var request = &instancepb.CreateInstanceRequest{
-		Parent:     formattedParent,
-		InstanceId: instanceId,
-		Instance:   instance,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	respLRO, err := c.CreateInstance(context.Background(), request)
-	if err != nil {
-		t.Fatal(err)
-	}
-	resp, err := respLRO.Wait(context.Background())
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockInstanceAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	if want, got := expectedResponse, resp; !proto.Equal(want, got) {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestInstanceAdminCreateInstanceError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockInstanceAdmin.err = nil
-	mockInstanceAdmin.resps = append(mockInstanceAdmin.resps[:0], &longrunningpb.Operation{
-		Name: "longrunning-test",
-		Done: true,
-		Result: &longrunningpb.Operation_Error{
-			Error: &status.Status{
-				Code:    int32(errCode),
-				Message: "test error",
-			},
-		},
-	})
-
-	var formattedParent string = InstanceAdminProjectPath("[PROJECT]")
-	var instanceId string = "instanceId-2101995259"
-	var instance *instancepb.Instance = &instancepb.Instance{}
-	var request = &instancepb.CreateInstanceRequest{
-		Parent:     formattedParent,
-		InstanceId: instanceId,
-		Instance:   instance,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	respLRO, err := c.CreateInstance(context.Background(), request)
-	if err != nil {
-		t.Fatal(err)
-	}
-	resp, err := respLRO.Wait(context.Background())
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
-func TestInstanceAdminUpdateInstance(t *testing.T) {
-	var name string = "name3373707"
-	var config string = "config-1354792126"
-	var displayName string = "displayName1615086568"
-	var nodeCount int32 = 1539922066
-	var expectedResponse = &instancepb.Instance{
-		Name:        name,
-		Config:      config,
-		DisplayName: displayName,
-		NodeCount:   nodeCount,
-	}
-
-	mockInstanceAdmin.err = nil
-	mockInstanceAdmin.reqs = nil
-
-	any, err := ptypes.MarshalAny(expectedResponse)
-	if err != nil {
-		t.Fatal(err)
-	}
-	mockInstanceAdmin.resps = append(mockInstanceAdmin.resps[:0], &longrunningpb.Operation{
-		Name:   "longrunning-test",
-		Done:   true,
-		Result: &longrunningpb.Operation_Response{Response: any},
-	})
-
-	var instance *instancepb.Instance = &instancepb.Instance{}
-	var fieldMask *field_maskpb.FieldMask = &field_maskpb.FieldMask{}
-	var request = &instancepb.UpdateInstanceRequest{
-		Instance:  instance,
-		FieldMask: fieldMask,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	respLRO, err := c.UpdateInstance(context.Background(), request)
-	if err != nil {
-		t.Fatal(err)
-	}
-	resp, err := respLRO.Wait(context.Background())
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockInstanceAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	if want, got := expectedResponse, resp; !proto.Equal(want, got) {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestInstanceAdminUpdateInstanceError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockInstanceAdmin.err = nil
-	mockInstanceAdmin.resps = append(mockInstanceAdmin.resps[:0], &longrunningpb.Operation{
-		Name: "longrunning-test",
-		Done: true,
-		Result: &longrunningpb.Operation_Error{
-			Error: &status.Status{
-				Code:    int32(errCode),
-				Message: "test error",
-			},
-		},
-	})
-
-	var instance *instancepb.Instance = &instancepb.Instance{}
-	var fieldMask *field_maskpb.FieldMask = &field_maskpb.FieldMask{}
-	var request = &instancepb.UpdateInstanceRequest{
-		Instance:  instance,
-		FieldMask: fieldMask,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	respLRO, err := c.UpdateInstance(context.Background(), request)
-	if err != nil {
-		t.Fatal(err)
-	}
-	resp, err := respLRO.Wait(context.Background())
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
-func TestInstanceAdminDeleteInstance(t *testing.T) {
-	var expectedResponse *emptypb.Empty = &emptypb.Empty{}
-
-	mockInstanceAdmin.err = nil
-	mockInstanceAdmin.reqs = nil
-
-	mockInstanceAdmin.resps = append(mockInstanceAdmin.resps[:0], expectedResponse)
-
-	var formattedName string = InstanceAdminInstancePath("[PROJECT]", "[INSTANCE]")
-	var request = &instancepb.DeleteInstanceRequest{
-		Name: formattedName,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	err = c.DeleteInstance(context.Background(), request)
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockInstanceAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-}
-
-func TestInstanceAdminDeleteInstanceError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockInstanceAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedName string = InstanceAdminInstancePath("[PROJECT]", "[INSTANCE]")
-	var request = &instancepb.DeleteInstanceRequest{
-		Name: formattedName,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	err = c.DeleteInstance(context.Background(), request)
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-}
-func TestInstanceAdminSetIamPolicy(t *testing.T) {
-	var version int32 = 351608024
-	var etag []byte = []byte("21")
-	var expectedResponse = &iampb.Policy{
-		Version: version,
-		Etag:    etag,
-	}
-
-	mockInstanceAdmin.err = nil
-	mockInstanceAdmin.reqs = nil
-
-	mockInstanceAdmin.resps = append(mockInstanceAdmin.resps[:0], expectedResponse)
-
-	var formattedResource string = InstanceAdminInstancePath("[PROJECT]", "[INSTANCE]")
-	var policy *iampb.Policy = &iampb.Policy{}
-	var request = &iampb.SetIamPolicyRequest{
-		Resource: formattedResource,
-		Policy:   policy,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.SetIamPolicy(context.Background(), request)
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockInstanceAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	if want, got := expectedResponse, resp; !proto.Equal(want, got) {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestInstanceAdminSetIamPolicyError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockInstanceAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedResource string = InstanceAdminInstancePath("[PROJECT]", "[INSTANCE]")
-	var policy *iampb.Policy = &iampb.Policy{}
-	var request = &iampb.SetIamPolicyRequest{
-		Resource: formattedResource,
-		Policy:   policy,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.SetIamPolicy(context.Background(), request)
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
-func TestInstanceAdminGetIamPolicy(t *testing.T) {
-	var version int32 = 351608024
-	var etag []byte = []byte("21")
-	var expectedResponse = &iampb.Policy{
-		Version: version,
-		Etag:    etag,
-	}
-
-	mockInstanceAdmin.err = nil
-	mockInstanceAdmin.reqs = nil
-
-	mockInstanceAdmin.resps = append(mockInstanceAdmin.resps[:0], expectedResponse)
-
-	var formattedResource string = InstanceAdminInstancePath("[PROJECT]", "[INSTANCE]")
-	var request = &iampb.GetIamPolicyRequest{
-		Resource: formattedResource,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.GetIamPolicy(context.Background(), request)
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockInstanceAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	if want, got := expectedResponse, resp; !proto.Equal(want, got) {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestInstanceAdminGetIamPolicyError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockInstanceAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedResource string = InstanceAdminInstancePath("[PROJECT]", "[INSTANCE]")
-	var request = &iampb.GetIamPolicyRequest{
-		Resource: formattedResource,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.GetIamPolicy(context.Background(), request)
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
-func TestInstanceAdminTestIamPermissions(t *testing.T) {
-	var expectedResponse *iampb.TestIamPermissionsResponse = &iampb.TestIamPermissionsResponse{}
-
-	mockInstanceAdmin.err = nil
-	mockInstanceAdmin.reqs = nil
-
-	mockInstanceAdmin.resps = append(mockInstanceAdmin.resps[:0], expectedResponse)
-
-	var formattedResource string = InstanceAdminInstancePath("[PROJECT]", "[INSTANCE]")
-	var permissions []string = nil
-	var request = &iampb.TestIamPermissionsRequest{
-		Resource:    formattedResource,
-		Permissions: permissions,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.TestIamPermissions(context.Background(), request)
-
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if want, got := request, mockInstanceAdmin.reqs[0]; !proto.Equal(want, got) {
-		t.Errorf("wrong request %q, want %q", got, want)
-	}
-
-	if want, got := expectedResponse, resp; !proto.Equal(want, got) {
-		t.Errorf("wrong response %q, want %q)", got, want)
-	}
-}
-
-func TestInstanceAdminTestIamPermissionsError(t *testing.T) {
-	errCode := codes.PermissionDenied
-	mockInstanceAdmin.err = grpc.Errorf(errCode, "test error")
-
-	var formattedResource string = InstanceAdminInstancePath("[PROJECT]", "[INSTANCE]")
-	var permissions []string = nil
-	var request = &iampb.TestIamPermissionsRequest{
-		Resource:    formattedResource,
-		Permissions: permissions,
-	}
-
-	c, err := NewInstanceAdminClient(context.Background(), clientOpt)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	resp, err := c.TestIamPermissions(context.Background(), request)
-
-	if c := grpc.Code(err); c != errCode {
-		t.Errorf("got error code %q, want %q", c, errCode)
-	}
-	_ = resp
-}
diff --git a/vendor/cloud.google.com/go/spanner/backoff.go b/vendor/cloud.google.com/go/spanner/backoff.go
deleted file mode 100644
index d38723843..000000000
--- a/vendor/cloud.google.com/go/spanner/backoff.go
+++ /dev/null
@@ -1,58 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"math/rand"
-	"time"
-)
-
-const (
-	// minBackoff is the minimum backoff used by default.
-	minBackoff = 1 * time.Second
-	// maxBackoff is the maximum backoff used by default.
-	maxBackoff = 32 * time.Second
-	// jitter is the jitter factor.
-	jitter = 0.4
-	// rate is the rate of exponential increase in the backoff.
-	rate = 1.3
-)
-
-var defaultBackoff = exponentialBackoff{minBackoff, maxBackoff}
-
-type exponentialBackoff struct {
-	min, max time.Duration
-}
-
-// delay calculates the delay that should happen at n-th
-// exponential backoff in a series.
-func (b exponentialBackoff) delay(retries int) time.Duration {
-	min, max := float64(b.min), float64(b.max)
-	delay := min
-	for delay < max && retries > 0 {
-		delay *= rate
-		retries--
-	}
-	if delay > max {
-		delay = max
-	}
-	delay -= delay * jitter * rand.Float64()
-	if delay < min {
-		delay = min
-	}
-	return time.Duration(delay)
-}
diff --git a/vendor/cloud.google.com/go/spanner/backoff_test.go b/vendor/cloud.google.com/go/spanner/backoff_test.go
deleted file mode 100644
index 7a0314e81..000000000
--- a/vendor/cloud.google.com/go/spanner/backoff_test.go
+++ /dev/null
@@ -1,62 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"math"
-	"time"
-
-	"testing"
-)
-
-// Test if exponential backoff helper can produce correct series of
-// retry delays.
-func TestBackoff(t *testing.T) {
-	b := exponentialBackoff{minBackoff, maxBackoff}
-	tests := []struct {
-		retries int
-		min     time.Duration
-		max     time.Duration
-	}{
-		{
-			retries: 0,
-			min:     minBackoff,
-			max:     minBackoff,
-		},
-		{
-			retries: 1,
-			min:     minBackoff,
-			max:     time.Duration(rate * float64(minBackoff)),
-		},
-		{
-			retries: 3,
-			min:     time.Duration(math.Pow(rate, 3) * (1 - jitter) * float64(minBackoff)),
-			max:     time.Duration(math.Pow(rate, 3) * float64(minBackoff)),
-		},
-		{
-			retries: 1000,
-			min:     time.Duration((1 - jitter) * float64(maxBackoff)),
-			max:     maxBackoff,
-		},
-	}
-	for _, test := range tests {
-		got := b.delay(test.retries)
-		if float64(got) < float64(test.min) || float64(got) > float64(test.max) {
-			t.Errorf("delay(%v) = %v, want in range [%v, %v]", test.retries, got, test.min, test.max)
-		}
-	}
-}
diff --git a/vendor/cloud.google.com/go/spanner/client.go b/vendor/cloud.google.com/go/spanner/client.go
deleted file mode 100644
index 4ccc9333a..000000000
--- a/vendor/cloud.google.com/go/spanner/client.go
+++ /dev/null
@@ -1,322 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"fmt"
-	"regexp"
-	"sync/atomic"
-	"time"
-
-	"cloud.google.com/go/internal/version"
-	"golang.org/x/net/context"
-	"google.golang.org/api/option"
-	"google.golang.org/api/transport"
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/metadata"
-)
-
-const (
-	prodAddr = "spanner.googleapis.com:443"
-
-	// resourcePrefixHeader is the name of the metadata header used to indicate
-	// the resource being operated on.
-	resourcePrefixHeader = "google-cloud-resource-prefix"
-	// apiClientHeader is the name of the metadata header used to indicate client
-	// information.
-	apiClientHeader = "x-goog-api-client"
-
-	// numChannels is the default value for NumChannels of client
-	numChannels = 4
-)
-
-const (
-	// Scope is the scope for Cloud Spanner Data API.
-	Scope = "https://www.googleapis.com/auth/spanner.data"
-
-	// AdminScope is the scope for Cloud Spanner Admin APIs.
-	AdminScope = "https://www.googleapis.com/auth/spanner.admin"
-)
-
-var (
-	validDBPattern  = regexp.MustCompile("^projects/[^/]+/instances/[^/]+/databases/[^/]+$")
-	clientUserAgent = fmt.Sprintf("gl-go/%s gccl/%s grpc/%s", version.Go(), version.Repo, grpc.Version)
-)
-
-func validDatabaseName(db string) error {
-	if matched := validDBPattern.MatchString(db); !matched {
-		return fmt.Errorf("database name %q should conform to pattern %q",
-			db, validDBPattern.String())
-	}
-	return nil
-}
-
-// Client is a client for reading and writing data to a Cloud Spanner database.  A
-// client is safe to use concurrently, except for its Close method.
-type Client struct {
-	// rr must be accessed through atomic operations.
-	rr       uint32
-	conns    []*grpc.ClientConn
-	clients  []sppb.SpannerClient
-	database string
-	// Metadata to be sent with each request.
-	md           metadata.MD
-	idleSessions *sessionPool
-}
-
-// ClientConfig has configurations for the client.
-type ClientConfig struct {
-	// NumChannels is the number of GRPC channels.
-	// If zero, numChannels is used.
-	NumChannels int
-	co          []option.ClientOption
-	// SessionPoolConfig is the configuration for session pool.
-	SessionPoolConfig
-}
-
-// errDial returns error for dialing to Cloud Spanner.
-func errDial(ci int, err error) error {
-	e := toSpannerError(err).(*Error)
-	e.decorate(fmt.Sprintf("dialing fails for channel[%v]", ci))
-	return e
-}
-
-func contextWithOutgoingMetadata(ctx context.Context, md metadata.MD) context.Context {
-	existing, ok := metadata.FromOutgoingContext(ctx)
-	if ok {
-		md = metadata.Join(existing, md)
-	}
-	return metadata.NewOutgoingContext(ctx, md)
-}
-
-// NewClient creates a client to a database. A valid database name has the
-// form projects/PROJECT_ID/instances/INSTANCE_ID/databases/DATABASE_ID. It uses a default
-// configuration.
-func NewClient(ctx context.Context, database string, opts ...option.ClientOption) (*Client, error) {
-	return NewClientWithConfig(ctx, database, ClientConfig{}, opts...)
-}
-
-// NewClientWithConfig creates a client to a database. A valid database name has the
-// form projects/PROJECT_ID/instances/INSTANCE_ID/databases/DATABASE_ID.
-func NewClientWithConfig(ctx context.Context, database string, config ClientConfig, opts ...option.ClientOption) (*Client, error) {
-	// Validate database path.
-	if err := validDatabaseName(database); err != nil {
-		return nil, err
-	}
-	c := &Client{
-		database: database,
-		md: metadata.Pairs(
-			resourcePrefixHeader, database,
-			apiClientHeader, clientUserAgent),
-	}
-	allOpts := []option.ClientOption{option.WithEndpoint(prodAddr), option.WithScopes(Scope), option.WithUserAgent(clientUserAgent), option.WithGRPCDialOption(grpc.WithDefaultCallOptions(grpc.MaxCallSendMsgSize(100<<20), grpc.MaxCallRecvMsgSize(100<<20)))}
-	allOpts = append(allOpts, opts...)
-	// Prepare gRPC channels.
-	if config.NumChannels == 0 {
-		config.NumChannels = numChannels
-	}
-	// Default MaxOpened sessions
-	if config.MaxOpened == 0 {
-		config.MaxOpened = uint64(config.NumChannels * 100)
-	}
-	if config.MaxBurst == 0 {
-		config.MaxBurst = 10
-	}
-	for i := 0; i < config.NumChannels; i++ {
-		conn, err := transport.DialGRPC(ctx, allOpts...)
-		if err != nil {
-			return nil, errDial(i, err)
-		}
-		c.conns = append(c.conns, conn)
-		c.clients = append(c.clients, sppb.NewSpannerClient(conn))
-	}
-	// Prepare session pool.
-	config.SessionPoolConfig.getRPCClient = func() (sppb.SpannerClient, error) {
-		// TODO: support more loadbalancing options.
-		return c.rrNext(), nil
-	}
-	sp, err := newSessionPool(database, config.SessionPoolConfig, c.md)
-	if err != nil {
-		c.Close()
-		return nil, err
-	}
-	c.idleSessions = sp
-	return c, nil
-}
-
-// rrNext returns the next available Cloud Spanner RPC client in a round-robin manner.
-func (c *Client) rrNext() sppb.SpannerClient {
-	return c.clients[atomic.AddUint32(&c.rr, 1)%uint32(len(c.clients))]
-}
-
-// Close closes the client.
-func (c *Client) Close() {
-	if c.idleSessions != nil {
-		c.idleSessions.close()
-	}
-	for _, conn := range c.conns {
-		conn.Close()
-	}
-}
-
-// Single provides a read-only snapshot transaction optimized for the case
-// where only a single read or query is needed.  This is more efficient than
-// using ReadOnlyTransaction() for a single read or query.
-//
-// Single will use a strong TimestampBound by default. Use
-// ReadOnlyTransaction.WithTimestampBound to specify a different
-// TimestampBound. A non-strong bound can be used to reduce latency, or
-// "time-travel" to prior versions of the database, see the documentation of
-// TimestampBound for details.
-func (c *Client) Single() *ReadOnlyTransaction {
-	t := &ReadOnlyTransaction{singleUse: true, sp: c.idleSessions}
-	t.txReadOnly.txReadEnv = t
-	return t
-}
-
-// ReadOnlyTransaction returns a ReadOnlyTransaction that can be used for
-// multiple reads from the database.  You must call Close() when the
-// ReadOnlyTransaction is no longer needed to release resources on the server.
-//
-// ReadOnlyTransaction will use a strong TimestampBound by default.  Use
-// ReadOnlyTransaction.WithTimestampBound to specify a different
-// TimestampBound.  A non-strong bound can be used to reduce latency, or
-// "time-travel" to prior versions of the database, see the documentation of
-// TimestampBound for details.
-func (c *Client) ReadOnlyTransaction() *ReadOnlyTransaction {
-	t := &ReadOnlyTransaction{
-		singleUse:       false,
-		sp:              c.idleSessions,
-		txReadyOrClosed: make(chan struct{}),
-	}
-	t.txReadOnly.txReadEnv = t
-	return t
-}
-
-type transactionInProgressKey struct{}
-
-func checkNestedTxn(ctx context.Context) error {
-	if ctx.Value(transactionInProgressKey{}) != nil {
-		return spannerErrorf(codes.FailedPrecondition, "Cloud Spanner does not support nested transactions")
-	}
-	return nil
-}
-
-// ReadWriteTransaction executes a read-write transaction, with retries as
-// necessary.
-//
-// The function f will be called one or more times. It must not maintain
-// any state between calls.
-//
-// If the transaction cannot be committed or if f returns an IsAborted error,
-// ReadWriteTransaction will call f again. It will continue to call f until the
-// transaction can be committed or the Context times out or is cancelled.  If f
-// returns an error other than IsAborted, ReadWriteTransaction will abort the
-// transaction and return the error.
-//
-// To limit the number of retries, set a deadline on the Context rather than
-// using a fixed limit on the number of attempts. ReadWriteTransaction will
-// retry as needed until that deadline is met.
-func (c *Client) ReadWriteTransaction(ctx context.Context, f func(context.Context, *ReadWriteTransaction) error) (time.Time, error) {
-	if err := checkNestedTxn(ctx); err != nil {
-		return time.Time{}, err
-	}
-	var (
-		ts time.Time
-		sh *sessionHandle
-	)
-	err := runRetryable(ctx, func(ctx context.Context) error {
-		var (
-			err error
-			t   *ReadWriteTransaction
-		)
-		if sh == nil || sh.getID() == "" || sh.getClient() == nil {
-			// Session handle hasn't been allocated or has been destroyed.
-			sh, err = c.idleSessions.takeWriteSession(ctx)
-			if err != nil {
-				// If session retrieval fails, just fail the transaction.
-				return err
-			}
-			t = &ReadWriteTransaction{
-				sh: sh,
-				tx: sh.getTransactionID(),
-			}
-		} else {
-			t = &ReadWriteTransaction{
-				sh: sh,
-			}
-		}
-		t.txReadOnly.txReadEnv = t
-		if err = t.begin(ctx); err != nil {
-			// Mask error from begin operation as retryable error.
-			return errRetry(err)
-		}
-		ts, err = t.runInTransaction(ctx, f)
-		if err != nil {
-			return err
-		}
-		return nil
-	})
-	if sh != nil {
-		sh.recycle()
-	}
-	return ts, err
-}
-
-// applyOption controls the behavior of Client.Apply.
-type applyOption struct {
-	// If atLeastOnce == true, Client.Apply will execute the mutations on Cloud Spanner at least once.
-	atLeastOnce bool
-}
-
-// An ApplyOption is an optional argument to Apply.
-type ApplyOption func(*applyOption)
-
-// ApplyAtLeastOnce returns an ApplyOption that removes replay protection.
-//
-// With this option, Apply may attempt to apply mutations more than once; if
-// the mutations are not idempotent, this may lead to a failure being reported
-// when the mutation was applied more than once. For example, an insert may
-// fail with ALREADY_EXISTS even though the row did not exist before Apply was
-// called. For this reason, most users of the library will prefer not to use
-// this option.  However, ApplyAtLeastOnce requires only a single RPC, whereas
-// Apply's default replay protection may require an additional RPC.  So this
-// option may be appropriate for latency sensitive and/or high throughput blind
-// writing.
-func ApplyAtLeastOnce() ApplyOption {
-	return func(ao *applyOption) {
-		ao.atLeastOnce = true
-	}
-}
-
-// Apply applies a list of mutations atomically to the database.
-func (c *Client) Apply(ctx context.Context, ms []*Mutation, opts ...ApplyOption) (time.Time, error) {
-	ao := &applyOption{}
-	for _, opt := range opts {
-		opt(ao)
-	}
-	if !ao.atLeastOnce {
-		return c.ReadWriteTransaction(ctx, func(ctx context.Context, t *ReadWriteTransaction) error {
-			t.BufferWrite(ms)
-			return nil
-		})
-	}
-	t := &writeOnlyTransaction{c.idleSessions}
-	return t.applyAtLeastOnce(ctx, ms...)
-}
diff --git a/vendor/cloud.google.com/go/spanner/client_test.go b/vendor/cloud.google.com/go/spanner/client_test.go
deleted file mode 100644
index 643f863b7..000000000
--- a/vendor/cloud.google.com/go/spanner/client_test.go
+++ /dev/null
@@ -1,50 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"strings"
-	"testing"
-)
-
-// Test validDatabaseName()
-func TestValidDatabaseName(t *testing.T) {
-	validDbUri := "projects/spanner-cloud-test/instances/foo/databases/foodb"
-	invalidDbUris := []string{
-		// Completely wrong DB URI.
-		"foobarDB",
-		// Project ID contains "/".
-		"projects/spanner-cloud/test/instances/foo/databases/foodb",
-		// No instance ID.
-		"projects/spanner-cloud-test/instances//databases/foodb",
-	}
-	if err := validDatabaseName(validDbUri); err != nil {
-		t.Errorf("validateDatabaseName(%q) = %v, want nil", validDbUri, err)
-	}
-	for _, d := range invalidDbUris {
-		if err, wantErr := validDatabaseName(d), "should conform to pattern"; !strings.Contains(err.Error(), wantErr) {
-			t.Errorf("validateDatabaseName(%q) = %q, want error pattern %q", validDbUri, err, wantErr)
-		}
-	}
-}
-
-func TestReadOnlyTransactionClose(t *testing.T) {
-	// Closing a ReadOnlyTransaction shouldn't panic.
-	c := &Client{}
-	tx := c.ReadOnlyTransaction()
-	tx.Close()
-}
diff --git a/vendor/cloud.google.com/go/spanner/doc.go b/vendor/cloud.google.com/go/spanner/doc.go
deleted file mode 100644
index 88f0b3221..000000000
--- a/vendor/cloud.google.com/go/spanner/doc.go
+++ /dev/null
@@ -1,311 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-/*
-Package spanner provides a client for reading and writing to Cloud Spanner
-databases. See the packages under admin for clients that operate on databases
-and instances.
-
-Note: This package is in alpha. Backwards-incompatible changes may occur
-without notice.
-
-See https://cloud.google.com/spanner/docs/getting-started/go/ for an introduction
-to Cloud Spanner and additional help on using this API.
-
-Creating a Client
-
-To start working with this package, create a client that refers to the database
-of interest:
-
-    ctx := context.Background()
-    client, err := spanner.NewClient(ctx, "projects/P/instances/I/databases/D")
-    defer client.Close()
-    if err != nil {
-        // TODO: Handle error.
-    }
-
-Remember to close the client after use to free up the sessions in the session
-pool.
-
-
-Simple Reads and Writes
-
-Two Client methods, Apply and Single, work well for simple reads and writes. As
-a quick introduction, here we write a new row to the database and read it back:
-
-    _, err := client.Apply(ctx, []*spanner.Mutation{
-        spanner.Insert("Users",
-            []string{"name", "email"},
-            []interface{}{"alice", "a@example.com"})})
-    if err != nil {
-        // TODO: Handle error.
-    }
-    row, err := client.Single().ReadRow(ctx, "Users",
-        spanner.Key{"alice"}, []string{"email"})
-    if err != nil {
-        // TODO: Handle error.
-    }
-
-All the methods used above are discussed in more detail below.
-
-
-Keys
-
-Every Cloud Spanner row has a unique key, composed of one or more columns.
-Construct keys with a literal of type Key:
-
-   key1 := spanner.Key{"alice"}
-
-
-KeyRanges
-
-The keys of a Cloud Spanner table are ordered. You can specify ranges of keys
-using the KeyRange type:
-
-    kr1 := spanner.KeyRange{Start: key1, End: key2}
-
-By default, a KeyRange includes its start key but not its end key. Use
-the Kind field to specify other boundary conditions:
-
-    // include both keys
-    kr2 := spanner.KeyRange{Start: key1, End: key2, Kind: spanner.ClosedClosed}
-
-
-KeySets
-
-A KeySet represents a set of keys. A single Key or KeyRange can act as a KeySet. Use
-the KeySets function to build the union of several KeySets:
-
-    ks1 := spanner.KeySets(key1, key2, kr1, kr2)
-
-AllKeys returns a KeySet that refers to all the keys in a table:
-
-    ks2 := spanner.AllKeys()
-
-
-Transactions
-
-All Cloud Spanner reads and writes occur inside transactions. There are two
-types of transactions, read-only and read-write. Read-only transactions cannot
-change the database, do not acquire locks, and may access either the current
-database state or states in the past. Read-write transactions can read the
-database before writing to it, and always apply to the most recent database
-state.
-
-
-Single Reads
-
-The simplest and fastest transaction is a ReadOnlyTransaction that supports a
-single read operation. Use Client.Single to create such a transaction. You can
-chain the call to Single with a call to a Read method.
-
-When you only want one row whose key you know, use ReadRow. Provide the table
-name, key, and the columns you want to read:
-
-    row, err := client.Single().ReadRow(ctx, "Accounts", spanner.Key{"alice"}, []string{"balance"})
-
-Read multiple rows with the Read method. It takes a table name, KeySet, and list
-of columns:
-
-    iter := client.Single().Read(ctx, "Accounts", keyset1, columns)
-
-Read returns a RowIterator. You can call the Do method on the iterator and pass
-a callback:
-
-    err := iter.Do(func(row *Row) error {
-       // TODO: use row
-       return nil
-    })
-
-RowIterator also follows the standard pattern for the Google
-Cloud Client Libraries:
-
-    defer iter.Stop()
-    for {
-        row, err := iter.Next()
-        if err == iterator.Done {
-            break
-        }
-        if err != nil {
-            // TODO: Handle error.
-        }
-        // TODO: use row
-    }
-
-Always call Stop when you finish using an iterator this way, whether or not you
-iterate to the end. (Failing to call Stop could lead you to exhaust the
-database's session quota.)
-
-To read rows with an index, use ReadUsingIndex.
-
-Statements
-
-The most general form of reading uses SQL statements. Construct a Statement
-with NewStatement, setting any parameters using the Statement's Params map:
-
-    stmt := spanner.NewStatement("SELECT First, Last FROM SINGERS WHERE Last >= @start")
-    stmt.Params["start"] = "Dylan"
-
-You can also construct a Statement directly with a struct literal, providing
-your own map of parameters.
-
-Use the Query method to run the statement and obtain an iterator:
-
-    iter := client.Single().Query(ctx, stmt)
-
-
-Rows
-
-Once you have a Row, via an iterator or a call to ReadRow, you can extract
-column values in several ways. Pass in a pointer to a Go variable of the
-appropriate type when you extract a value.
-
-You can extract by column position or name:
-
-   err := row.Column(0, &name)
-   err = row.ColumnByName("balance", &balance)
-
-You can extract all the columns at once:
-
-   err = row.Columns(&name, &balance)
-
-Or you can define a Go struct that corresponds to your columns, and extract
-into that:
-
-   var s struct { Name string; Balance int64 }
-   err = row.ToStruct(&s)
-
-
-For Cloud Spanner columns that may contain NULL, use one of the NullXXX types,
-like NullString:
-
-    var ns spanner.NullString
-    if err =: row.Column(0, &ns); err != nil {
-        // TODO: Handle error.
-    }
-    if ns.Valid {
-        fmt.Println(ns.StringVal)
-    } else {
-        fmt.Println("column is NULL")
-    }
-
-
-Multiple Reads
-
-To perform more than one read in a transaction, use ReadOnlyTransaction:
-
-    txn := client.ReadOnlyTransaction()
-    defer txn.Close()
-    iter := txn.Query(ctx, stmt1)
-    // ...
-    iter =  txn.Query(ctx, stmt2)
-    // ...
-
-You must call Close when you are done with the transaction.
-
-
-Timestamps and Timestamp Bounds
-
-Cloud Spanner read-only transactions conceptually perform all their reads at a
-single moment in time, called the transaction's read timestamp. Once a read has
-started, you can call ReadOnlyTransaction's Timestamp method to obtain the read
-timestamp.
-
-By default, a transaction will pick the most recent time (a time where all
-previously committed transactions are visible) for its reads. This provides the
-freshest data, but may involve some delay. You can often get a quicker response
-if you are willing to tolerate "stale" data. You can control the read timestamp
-selected by a transaction by calling the WithTimestampBound method on the
-transaction before using it. For example, to perform a query on data that is at
-most one minute stale, use
-
-    client.Single().
-        WithTimestampBound(spanner.MaxStaleness(1*time.Minute)).
-        Query(ctx, stmt)
-
-See the documentation of TimestampBound for more details.
-
-
-Mutations
-
-To write values to a Cloud Spanner database, construct a Mutation. The spanner
-package has functions for inserting, updating and deleting rows. Except for the
-Delete methods, which take a Key or KeyRange, each mutation-building function
-comes in three varieties.
-
-One takes lists of columns and values along with the table name:
-
-    m1 := spanner.Insert("Users",
-        []string{"name", "email"},
-        []interface{}{"alice", "a@example.com"})
-
-One takes a map from column names to values:
-
-    m2 := spanner.InsertMap("Users", map[string]interface{}{
-        "name":  "alice",
-        "email": "a@example.com",
-    })
-
-And the third accepts a struct value, and determines the columns from the
-struct field names:
-
-    type User struct { Name, Email string }
-    u := User{Name: "alice", Email: "a@example.com"}
-    m3, err := spanner.InsertStruct("Users", u)
-
-
-Writes
-
-To apply a list of mutations to the database, use Apply:
-
-    _, err := client.Apply(ctx, []*spanner.Mutation{m1, m2, m3})
-
-If you need to read before writing in a single transaction, use a
-ReadWriteTransaction. ReadWriteTransactions may abort and need to be retried.
-You pass in a function to ReadWriteTransaction, and the client will handle the
-retries automatically. Use the transaction's BufferWrite method to buffer
-mutations, which will all be executed at the end of the transaction:
-
-    _, err := client.ReadWriteTransaction(ctx, func(txn *spanner.ReadWriteTransaction) error {
-        var balance int64
-        row, err := txn.ReadRow(ctx, "Accounts", spanner.Key{"alice"}, []string{"balance"})
-        if err != nil {
-            // This function will be called again if this is an IsAborted error.
-            return err
-        }
-        if err := row.Column(0, &balance); err != nil {
-            return err
-        }
-
-        if balance <= 10 {
-            return errors.New("insufficient funds in account")
-        }
-        balance -= 10
-        m := spanner.Update("Accounts", []string{"user", "balance"}, []interface{}{"alice", balance})
-        txn.BufferWrite([]*spanner.Mutation{m})
-
-        // The buffered mutation will be committed.  If the commit
-        // fails with an IsAborted error, this function will be called
-        // again.
-        return nil
-    })
-
-Authentication
-
-See examples of authorization and authentication at
-https://godoc.org/cloud.google.com/go#pkg-examples.
-*/
-package spanner // import "cloud.google.com/go/spanner"
diff --git a/vendor/cloud.google.com/go/spanner/errors.go b/vendor/cloud.google.com/go/spanner/errors.go
deleted file mode 100644
index 13106f2ed..000000000
--- a/vendor/cloud.google.com/go/spanner/errors.go
+++ /dev/null
@@ -1,108 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"fmt"
-
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/metadata"
-)
-
-// Error is the structured error returned by Cloud Spanner client.
-type Error struct {
-	// Code is the canonical error code for describing the nature of a
-	// particular error.
-	Code codes.Code
-	// Desc explains more details of the error.
-	Desc string
-	// trailers are the trailers returned in the response, if any.
-	trailers metadata.MD
-}
-
-// Error implements error.Error.
-func (e *Error) Error() string {
-	if e == nil {
-		return fmt.Sprintf("spanner: OK")
-	}
-	return fmt.Sprintf("spanner: code = %q, desc = %q", e.Code, e.Desc)
-}
-
-// decorate decorates an existing spanner.Error with more information.
-func (e *Error) decorate(info string) {
-	e.Desc = fmt.Sprintf("%v, %v", info, e.Desc)
-}
-
-// spannerErrorf generates a *spanner.Error with the given error code and
-// description.
-func spannerErrorf(ec codes.Code, format string, args ...interface{}) error {
-	return &Error{
-		Code: ec,
-		Desc: fmt.Sprintf(format, args...),
-	}
-}
-
-// toSpannerError converts general Go error to *spanner.Error.
-func toSpannerError(err error) error {
-	return toSpannerErrorWithMetadata(err, nil)
-}
-
-// toSpannerErrorWithMetadata converts general Go error and grpc trailers to *spanner.Error.
-// Note: modifies original error if trailers aren't nil
-func toSpannerErrorWithMetadata(err error, trailers metadata.MD) error {
-	if err == nil {
-		return nil
-	}
-	if se, ok := err.(*Error); ok {
-		if trailers != nil {
-			se.trailers = metadata.Join(se.trailers, trailers)
-		}
-		return se
-	}
-	if grpc.Code(err) == codes.Unknown {
-		return &Error{codes.Unknown, err.Error(), trailers}
-	}
-	return &Error{grpc.Code(err), grpc.ErrorDesc(err), trailers}
-}
-
-// ErrCode extracts the canonical error code from a Go error.
-func ErrCode(err error) codes.Code {
-	se, ok := toSpannerError(err).(*Error)
-	if !ok {
-		return codes.Unknown
-	}
-	return se.Code
-}
-
-// ErrDesc extracts the Cloud Spanner error description from a Go error.
-func ErrDesc(err error) string {
-	se, ok := toSpannerError(err).(*Error)
-	if !ok {
-		return err.Error()
-	}
-	return se.Desc
-}
-
-// errTrailers extracts the grpc trailers if present from a Go error.
-func errTrailers(err error) metadata.MD {
-	se, ok := err.(*Error)
-	if !ok {
-		return nil
-	}
-	return se.trailers
-}
diff --git a/vendor/cloud.google.com/go/spanner/examples_test.go b/vendor/cloud.google.com/go/spanner/examples_test.go
deleted file mode 100644
index 4cd19451c..000000000
--- a/vendor/cloud.google.com/go/spanner/examples_test.go
+++ /dev/null
@@ -1,536 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner_test
-
-import (
-	"errors"
-	"fmt"
-	"time"
-
-	"cloud.google.com/go/spanner"
-	"golang.org/x/net/context"
-	"google.golang.org/api/iterator"
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-)
-
-func ExampleNewClient() {
-	ctx := context.Background()
-	const myDB = "projects/my-project/instances/my-instance/database/my-db"
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	_ = client // TODO: Use client.
-}
-
-const myDB = "projects/my-project/instances/my-instance/database/my-db"
-
-func ExampleNewClientWithConfig() {
-	ctx := context.Background()
-	const myDB = "projects/my-project/instances/my-instance/database/my-db"
-	client, err := spanner.NewClientWithConfig(ctx, myDB, spanner.ClientConfig{
-		NumChannels: 10,
-	})
-	if err != nil {
-		// TODO: Handle error.
-	}
-	_ = client     // TODO: Use client.
-	client.Close() // Close client when done.
-}
-
-func ExampleClient_Single() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	iter := client.Single().Query(ctx, spanner.NewStatement("SELECT FirstName FROM Singers"))
-	_ = iter // TODO: iterate using Next or Do.
-}
-
-func ExampleClient_ReadOnlyTransaction() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	t := client.ReadOnlyTransaction()
-	defer t.Close()
-	// TODO: Read with t using Read, ReadRow, ReadUsingIndex, or Query.
-}
-
-func ExampleClient_ReadWriteTransaction() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	_, err = client.ReadWriteTransaction(ctx, func(ctx context.Context, txn *spanner.ReadWriteTransaction) error {
-		var balance int64
-		row, err := txn.ReadRow(ctx, "Accounts", spanner.Key{"alice"}, []string{"balance"})
-		if err != nil {
-			// This function will be called again if this is an
-			// IsAborted error.
-			return err
-		}
-		if err := row.Column(0, &balance); err != nil {
-			return err
-		}
-
-		if balance <= 10 {
-			return errors.New("insufficient funds in account")
-		}
-		balance -= 10
-		m := spanner.Update("Accounts", []string{"user", "balance"}, []interface{}{"alice", balance})
-		return txn.BufferWrite([]*spanner.Mutation{m})
-		// The buffered mutation will be committed.  If the commit
-		// fails with an IsAborted error, this function will be called
-		// again.
-	})
-	if err != nil {
-		// TODO: Handle error.
-	}
-}
-
-func ExampleUpdate() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	_, err = client.ReadWriteTransaction(ctx, func(ctx context.Context, txn *spanner.ReadWriteTransaction) error {
-		row, err := txn.ReadRow(ctx, "Accounts", spanner.Key{"alice"}, []string{"balance"})
-		if err != nil {
-			return err
-		}
-		var balance int64
-		if err := row.Column(0, &balance); err != nil {
-			return err
-		}
-		return txn.BufferWrite([]*spanner.Mutation{
-			spanner.Update("Accounts", []string{"user", "balance"}, []interface{}{"alice", balance + 10}),
-		})
-	})
-	if err != nil {
-		// TODO: Handle error.
-	}
-}
-
-// This example is the same as the one for Update, except for the use of UpdateMap.
-func ExampleUpdateMap() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	_, err = client.ReadWriteTransaction(ctx, func(ctx context.Context, txn *spanner.ReadWriteTransaction) error {
-		row, err := txn.ReadRow(ctx, "Accounts", spanner.Key{"alice"}, []string{"balance"})
-		if err != nil {
-			return err
-		}
-		var balance int64
-		if err := row.Column(0, &balance); err != nil {
-			return err
-		}
-		return txn.BufferWrite([]*spanner.Mutation{
-			spanner.UpdateMap("Accounts", map[string]interface{}{
-				"user":    "alice",
-				"balance": balance + 10,
-			}),
-		})
-	})
-	if err != nil {
-		// TODO: Handle error.
-	}
-}
-
-// This example is the same as the one for Update, except for the use of UpdateStruct.
-func ExampleUpdateStruct() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	type account struct {
-		User    string `spanner:"user"`
-		Balance int64  `spanner:"balance"`
-	}
-	_, err = client.ReadWriteTransaction(ctx, func(ctx context.Context, txn *spanner.ReadWriteTransaction) error {
-		row, err := txn.ReadRow(ctx, "Accounts", spanner.Key{"alice"}, []string{"balance"})
-		if err != nil {
-			return err
-		}
-		var balance int64
-		if err := row.Column(0, &balance); err != nil {
-			return err
-		}
-		m, err := spanner.UpdateStruct("Accounts", account{
-			User:    "alice",
-			Balance: balance + 10,
-		})
-		if err != nil {
-			return err
-		}
-		return txn.BufferWrite([]*spanner.Mutation{m})
-	})
-	if err != nil {
-		// TODO: Handle error.
-	}
-}
-
-func ExampleClient_Apply() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	m := spanner.Update("Users", []string{"name", "email"}, []interface{}{"alice", "a@example.com"})
-	_, err = client.Apply(ctx, []*spanner.Mutation{m})
-	if err != nil {
-		// TODO: Handle error.
-	}
-}
-
-func ExampleInsert() {
-	m := spanner.Insert("Users", []string{"name", "email"}, []interface{}{"alice", "a@example.com"})
-	_ = m // TODO: use with Client.Apply or in a ReadWriteTransaction.
-}
-
-func ExampleInsertMap() {
-	m := spanner.InsertMap("Users", map[string]interface{}{
-		"name":  "alice",
-		"email": "a@example.com",
-	})
-	_ = m // TODO: use with Client.Apply or in a ReadWriteTransaction.
-}
-
-func ExampleInsertStruct() {
-	type User struct {
-		Name, Email string
-	}
-	u := User{Name: "alice", Email: "a@example.com"}
-	m, err := spanner.InsertStruct("Users", u)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	_ = m // TODO: use with Client.Apply or in a ReadWriteTransaction.
-}
-
-func ExampleDelete() {
-	m := spanner.Delete("Users", spanner.Key{"alice"})
-	_ = m // TODO: use with Client.Apply or in a ReadWriteTransaction.
-}
-
-func ExampleDelete_KeyRange() {
-	m := spanner.Delete("Users", spanner.KeyRange{
-		Start: spanner.Key{"alice"},
-		End:   spanner.Key{"bob"},
-		Kind:  spanner.ClosedClosed,
-	})
-	_ = m // TODO: use with Client.Apply or in a ReadWriteTransaction.
-}
-
-func ExampleRowIterator_Next() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	iter := client.Single().Query(ctx, spanner.NewStatement("SELECT FirstName FROM Singers"))
-	defer iter.Stop()
-	for {
-		row, err := iter.Next()
-		if err == iterator.Done {
-			break
-		}
-		if err != nil {
-			// TODO: Handle error.
-		}
-		var firstName string
-		if err := row.Column(0, &firstName); err != nil {
-			// TODO: Handle error.
-		}
-		fmt.Println(firstName)
-	}
-}
-
-func ExampleRowIterator_Do() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	iter := client.Single().Query(ctx, spanner.NewStatement("SELECT FirstName FROM Singers"))
-	err = iter.Do(func(r *spanner.Row) error {
-		var firstName string
-		if err := r.Column(0, &firstName); err != nil {
-			return err
-		}
-		fmt.Println(firstName)
-		return nil
-	})
-	if err != nil {
-		// TODO: Handle error.
-	}
-}
-
-func ExampleRow_Size() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	row, err := client.Single().ReadRow(ctx, "Accounts", spanner.Key{"alice"}, []string{"name", "balance"})
-	if err != nil {
-		// TODO: Handle error.
-	}
-	fmt.Println(row.Size()) // size is 2
-}
-
-func ExampleRow_ColumnName() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	row, err := client.Single().ReadRow(ctx, "Accounts", spanner.Key{"alice"}, []string{"name", "balance"})
-	if err != nil {
-		// TODO: Handle error.
-	}
-	fmt.Println(row.ColumnName(1)) // prints "balance"
-}
-
-func ExampleRow_ColumnIndex() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	row, err := client.Single().ReadRow(ctx, "Accounts", spanner.Key{"alice"}, []string{"name", "balance"})
-	if err != nil {
-		// TODO: Handle error.
-	}
-	index, err := row.ColumnIndex("balance")
-	if err != nil {
-		// TODO: Handle error.
-	}
-	fmt.Println(index)
-}
-
-func ExampleRow_ColumnNames() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	row, err := client.Single().ReadRow(ctx, "Accounts", spanner.Key{"alice"}, []string{"name", "balance"})
-	if err != nil {
-		// TODO: Handle error.
-	}
-	fmt.Println(row.ColumnNames())
-}
-
-func ExampleRow_ColumnByName() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	row, err := client.Single().ReadRow(ctx, "Accounts", spanner.Key{"alice"}, []string{"name", "balance"})
-	if err != nil {
-		// TODO: Handle error.
-	}
-	var balance int64
-	if err := row.ColumnByName("balance", &balance); err != nil {
-		// TODO: Handle error.
-	}
-	fmt.Println(balance)
-}
-
-func ExampleRow_Columns() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	row, err := client.Single().ReadRow(ctx, "Accounts", spanner.Key{"alice"}, []string{"name", "balance"})
-	if err != nil {
-		// TODO: Handle error.
-	}
-	var name string
-	var balance int64
-	if err := row.Columns(&name, &balance); err != nil {
-		// TODO: Handle error.
-	}
-	fmt.Println(name, balance)
-}
-
-func ExampleRow_ToStruct() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	row, err := client.Single().ReadRow(ctx, "Accounts", spanner.Key{"alice"}, []string{"name", "balance"})
-	if err != nil {
-		// TODO: Handle error.
-	}
-
-	type Account struct {
-		Name    string
-		Balance int64
-	}
-
-	var acct Account
-	if err := row.ToStruct(&acct); err != nil {
-		// TODO: Handle error.
-	}
-	fmt.Println(acct)
-}
-
-func ExampleReadOnlyTransaction_Read() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	iter := client.Single().Read(ctx, "Users",
-		spanner.KeySets(spanner.Key{"alice"}, spanner.Key{"bob"}),
-		[]string{"name", "email"})
-	_ = iter // TODO: iterate using Next or Do.
-}
-
-func ExampleReadOnlyTransaction_ReadUsingIndex() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	iter := client.Single().ReadUsingIndex(ctx, "Users",
-		"UsersByEmail",
-		spanner.KeySets(spanner.Key{"a@example.com"}, spanner.Key{"b@example.com"}),
-		[]string{"name", "email"})
-	_ = iter // TODO: iterate using Next or Do.
-}
-
-func ExampleReadOnlyTransaction_ReadRow() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	row, err := client.Single().ReadRow(ctx, "Users", spanner.Key{"alice"},
-		[]string{"name", "email"})
-	if err != nil {
-		// TODO: Handle error.
-	}
-	_ = row // TODO: use row
-}
-
-func ExampleReadOnlyTransaction_Query() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	iter := client.Single().Query(ctx, spanner.NewStatement("SELECT FirstName FROM Singers"))
-	_ = iter // TODO: iterate using Next or Do.
-}
-
-func ExampleNewStatement() {
-	stmt := spanner.NewStatement("SELECT FirstName, LastName FROM SINGERS WHERE LastName >= @start")
-	stmt.Params["start"] = "Dylan"
-	// TODO: Use stmt in Query.
-}
-
-func ExampleNewStatement_structLiteral() {
-	stmt := spanner.Statement{
-		SQL:    "SELECT FirstName, LastName FROM SINGERS WHERE LastName >= @start",
-		Params: map[string]interface{}{"start": "Dylan"},
-	}
-	_ = stmt // TODO: Use stmt in Query.
-}
-
-func ExampleReadOnlyTransaction_Timestamp() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	txn := client.Single()
-	row, err := txn.ReadRow(ctx, "Users", spanner.Key{"alice"},
-		[]string{"name", "email"})
-	if err != nil {
-		// TODO: Handle error.
-	}
-	readTimestamp, err := txn.Timestamp()
-	if err != nil {
-		// TODO: Handle error.
-	}
-	fmt.Println("read happened at", readTimestamp)
-	_ = row // TODO: use row
-}
-
-func ExampleReadOnlyTransaction_WithTimestampBound() {
-	ctx := context.Background()
-	client, err := spanner.NewClient(ctx, myDB)
-	if err != nil {
-		// TODO: Handle error.
-	}
-	txn := client.Single().WithTimestampBound(spanner.MaxStaleness(30 * time.Second))
-	row, err := txn.ReadRow(ctx, "Users", spanner.Key{"alice"}, []string{"name", "email"})
-	if err != nil {
-		// TODO: Handle error.
-	}
-	_ = row // TODO: use row
-	readTimestamp, err := txn.Timestamp()
-	if err != nil {
-		// TODO: Handle error.
-	}
-	fmt.Println("read happened at", readTimestamp)
-}
-
-func ExampleNewGenericColumnValue_Decode() {
-	// In real applications, rows can be retrieved by methods like client.Single().ReadRow().
-	row, err := spanner.NewRow([]string{"intCol", "strCol"}, []interface{}{42, "my-text"})
-	if err != nil {
-		// TODO: Handle error.
-	}
-	for i := 0; i < row.Size(); i++ {
-		var col spanner.GenericColumnValue
-		if err := row.Column(i, &col); err != nil {
-			// TODO: Handle error.
-		}
-		switch col.Type.Code {
-		case sppb.TypeCode_INT64:
-			var v int64
-			if err := col.Decode(&v); err != nil {
-				// TODO: Handle error.
-			}
-			fmt.Println("int", v)
-		case sppb.TypeCode_STRING:
-			var v string
-			if err := col.Decode(&v); err != nil {
-				// TODO: Handle error.
-			}
-			fmt.Println("string", v)
-		}
-	}
-	// Output:
-	// int 42
-	// string my-text
-}
diff --git a/vendor/cloud.google.com/go/spanner/internal/testutil/mockclient.go b/vendor/cloud.google.com/go/spanner/internal/testutil/mockclient.go
deleted file mode 100644
index f278c7cc6..000000000
--- a/vendor/cloud.google.com/go/spanner/internal/testutil/mockclient.go
+++ /dev/null
@@ -1,355 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package testutil
-
-import (
-	"errors"
-	"fmt"
-	"reflect"
-	"sync"
-	"testing"
-	"time"
-
-	"golang.org/x/net/context"
-
-	"github.com/golang/protobuf/ptypes/empty"
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-	pbt "github.com/golang/protobuf/ptypes/timestamp"
-
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
-)
-
-// Action is a mocked RPC activity that MockCloudSpannerClient will take.
-type Action struct {
-	method string
-	err    error
-}
-
-// NewAction creates Action objects.
-func NewAction(m string, e error) Action {
-	return Action{m, e}
-}
-
-// MockCloudSpannerClient is a mock implementation of sppb.SpannerClient.
-type MockCloudSpannerClient struct {
-	mu sync.Mutex
-	t  *testing.T
-	// Live sessions on the client.
-	sessions map[string]bool
-	// Expected set of actions that will be executed by the client.
-	actions []Action
-	// Session ping history
-	pings []string
-	// Injected error, will be returned by all APIs
-	injErr map[string]error
-	// nice client will not fail on any request
-	nice bool
-}
-
-// NewMockCloudSpannerClient creates new MockCloudSpannerClient instance.
-func NewMockCloudSpannerClient(t *testing.T, acts ...Action) *MockCloudSpannerClient {
-	mc := &MockCloudSpannerClient{t: t, sessions: map[string]bool{}, injErr: map[string]error{}}
-	mc.SetActions(acts...)
-	return mc
-}
-
-// MakeNice makes this a nice mock which will not fail on any request.
-func (m *MockCloudSpannerClient) MakeNice() {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	m.nice = true
-}
-
-// MakeStrict makes this a strict mock which will fail on any unexpected request.
-func (m *MockCloudSpannerClient) MakeStrict() {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	m.nice = false
-}
-
-// InjectError injects a global error that will be returned by all APIs regardless of
-// the actions array.
-func (m *MockCloudSpannerClient) InjectError(method string, err error) {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	m.injErr[method] = err
-}
-
-// SetActions sets the new set of expected actions to MockCloudSpannerClient.
-func (m *MockCloudSpannerClient) SetActions(acts ...Action) {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	m.actions = []Action{}
-	for _, act := range acts {
-		m.actions = append(m.actions, act)
-	}
-}
-
-// DumpPings dumps the ping history.
-func (m *MockCloudSpannerClient) DumpPings() []string {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	return append([]string(nil), m.pings...)
-}
-
-// DumpSessions dumps the internal session table.
-func (m *MockCloudSpannerClient) DumpSessions() map[string]bool {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	st := map[string]bool{}
-	for s, v := range m.sessions {
-		st[s] = v
-	}
-	return st
-}
-
-// CreateSession is a placeholder for SpannerClient.CreateSession.
-func (m *MockCloudSpannerClient) CreateSession(c context.Context, r *sppb.CreateSessionRequest, opts ...grpc.CallOption) (*sppb.Session, error) {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	if err := m.injErr["CreateSession"]; err != nil {
-		return nil, err
-	}
-	s := &sppb.Session{}
-	if r.Database != "mockdb" {
-		// Reject other databases
-		return s, grpc.Errorf(codes.NotFound, fmt.Sprintf("database not found: %v", r.Database))
-	}
-	// Generate & record session name.
-	s.Name = fmt.Sprintf("mockdb-%v", time.Now().UnixNano())
-	m.sessions[s.Name] = true
-	return s, nil
-}
-
-// GetSession is a placeholder for SpannerClient.GetSession.
-func (m *MockCloudSpannerClient) GetSession(c context.Context, r *sppb.GetSessionRequest, opts ...grpc.CallOption) (*sppb.Session, error) {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	if err := m.injErr["GetSession"]; err != nil {
-		return nil, err
-	}
-	m.pings = append(m.pings, r.Name)
-	if _, ok := m.sessions[r.Name]; !ok {
-		return nil, grpc.Errorf(codes.NotFound, fmt.Sprintf("Session not found: %v", r.Name))
-	}
-	return &sppb.Session{Name: r.Name}, nil
-}
-
-// DeleteSession is a placeholder for SpannerClient.DeleteSession.
-func (m *MockCloudSpannerClient) DeleteSession(c context.Context, r *sppb.DeleteSessionRequest, opts ...grpc.CallOption) (*empty.Empty, error) {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	if err := m.injErr["DeleteSession"]; err != nil {
-		return nil, err
-	}
-	if _, ok := m.sessions[r.Name]; !ok {
-		// Session not found.
-		return &empty.Empty{}, grpc.Errorf(codes.NotFound, fmt.Sprintf("Session not found: %v", r.Name))
-	}
-	// Delete session from in-memory table.
-	delete(m.sessions, r.Name)
-	return &empty.Empty{}, nil
-}
-
-// ExecuteSql is a placeholder for SpannerClient.ExecuteSql.
-func (m *MockCloudSpannerClient) ExecuteSql(c context.Context, r *sppb.ExecuteSqlRequest, opts ...grpc.CallOption) (*sppb.ResultSet, error) {
-	return nil, errors.New("Unimplemented")
-}
-
-// ExecuteStreamingSql is a mock implementation of SpannerClient.ExecuteStreamingSql.
-func (m *MockCloudSpannerClient) ExecuteStreamingSql(c context.Context, r *sppb.ExecuteSqlRequest, opts ...grpc.CallOption) (sppb.Spanner_ExecuteStreamingSqlClient, error) {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	if err := m.injErr["ExecuteStreamingSql"]; err != nil {
-		return nil, err
-	}
-	if len(m.actions) == 0 {
-		m.t.Fatalf("unexpected ExecuteStreamingSql executed")
-	}
-	act := m.actions[0]
-	m.actions = m.actions[1:]
-	if act.method != "ExecuteStreamingSql" {
-		m.t.Fatalf("unexpected ExecuteStreamingSql call, want action: %v", act)
-	}
-	wantReq := &sppb.ExecuteSqlRequest{
-		Session: "mocksession",
-		Transaction: &sppb.TransactionSelector{
-			Selector: &sppb.TransactionSelector_SingleUse{
-				SingleUse: &sppb.TransactionOptions{
-					Mode: &sppb.TransactionOptions_ReadOnly_{
-						ReadOnly: &sppb.TransactionOptions_ReadOnly{
-							TimestampBound: &sppb.TransactionOptions_ReadOnly_Strong{
-								Strong: true,
-							},
-							ReturnReadTimestamp: false,
-						},
-					},
-				},
-			},
-		},
-		Sql: "mockquery",
-		Params: &proto3.Struct{
-			Fields: map[string]*proto3.Value{"var1": &proto3.Value{Kind: &proto3.Value_StringValue{StringValue: "abc"}}},
-		},
-		ParamTypes: map[string]*sppb.Type{"var1": &sppb.Type{Code: sppb.TypeCode_STRING}},
-	}
-	if !reflect.DeepEqual(r, wantReq) {
-		return nil, fmt.Errorf("got query request: %v, want: %v", r, wantReq)
-	}
-	if act.err != nil {
-		return nil, act.err
-	}
-	return nil, errors.New("query never succeeds on mock client")
-}
-
-// Read is a placeholder for SpannerClient.Read.
-func (m *MockCloudSpannerClient) Read(c context.Context, r *sppb.ReadRequest, opts ...grpc.CallOption) (*sppb.ResultSet, error) {
-	m.t.Fatalf("Read is unimplemented")
-	return nil, errors.New("Unimplemented")
-}
-
-// StreamingRead is a placeholder for SpannerClient.StreamingRead.
-func (m *MockCloudSpannerClient) StreamingRead(c context.Context, r *sppb.ReadRequest, opts ...grpc.CallOption) (sppb.Spanner_StreamingReadClient, error) {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	if err := m.injErr["StreamingRead"]; err != nil {
-		return nil, err
-	}
-	if len(m.actions) == 0 {
-		m.t.Fatalf("unexpected StreamingRead executed")
-	}
-	act := m.actions[0]
-	m.actions = m.actions[1:]
-	if act.method != "StreamingRead" && act.method != "StreamingIndexRead" {
-		m.t.Fatalf("unexpected read call, want action: %v", act)
-	}
-	wantReq := &sppb.ReadRequest{
-		Session: "mocksession",
-		Transaction: &sppb.TransactionSelector{
-			Selector: &sppb.TransactionSelector_SingleUse{
-				SingleUse: &sppb.TransactionOptions{
-					Mode: &sppb.TransactionOptions_ReadOnly_{
-						ReadOnly: &sppb.TransactionOptions_ReadOnly{
-							TimestampBound: &sppb.TransactionOptions_ReadOnly_Strong{
-								Strong: true,
-							},
-							ReturnReadTimestamp: false,
-						},
-					},
-				},
-			},
-		},
-		Table:   "t_mock",
-		Columns: []string{"col1", "col2"},
-		KeySet: &sppb.KeySet{
-			[]*proto3.ListValue{
-				&proto3.ListValue{
-					Values: []*proto3.Value{
-						&proto3.Value{Kind: &proto3.Value_StringValue{StringValue: "foo"}},
-					},
-				},
-			},
-			[]*sppb.KeyRange{},
-			false,
-		},
-	}
-	if act.method == "StreamingIndexRead" {
-		wantReq.Index = "idx1"
-	}
-	if !reflect.DeepEqual(r, wantReq) {
-		return nil, fmt.Errorf("got query request: %v, want: %v", r, wantReq)
-	}
-	if act.err != nil {
-		return nil, act.err
-	}
-	return nil, errors.New("read never succeeds on mock client")
-}
-
-// BeginTransaction is a placeholder for SpannerClient.BeginTransaction.
-func (m *MockCloudSpannerClient) BeginTransaction(c context.Context, r *sppb.BeginTransactionRequest, opts ...grpc.CallOption) (*sppb.Transaction, error) {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	if !m.nice {
-		if err := m.injErr["BeginTransaction"]; err != nil {
-			return nil, err
-		}
-		if len(m.actions) == 0 {
-			m.t.Fatalf("unexpected Begin executed")
-		}
-		act := m.actions[0]
-		m.actions = m.actions[1:]
-		if act.method != "Begin" {
-			m.t.Fatalf("unexpected Begin call, want action: %v", act)
-		}
-		if act.err != nil {
-			return nil, act.err
-		}
-	}
-	resp := &sppb.Transaction{Id: []byte("transaction-1")}
-	if _, ok := r.Options.Mode.(*sppb.TransactionOptions_ReadOnly_); ok {
-		resp.ReadTimestamp = &pbt.Timestamp{Seconds: 3, Nanos: 4}
-	}
-	return resp, nil
-}
-
-// Commit is a placeholder for SpannerClient.Commit.
-func (m *MockCloudSpannerClient) Commit(c context.Context, r *sppb.CommitRequest, opts ...grpc.CallOption) (*sppb.CommitResponse, error) {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	if !m.nice {
-		if err := m.injErr["Commit"]; err != nil {
-			return nil, err
-		}
-		if len(m.actions) == 0 {
-			m.t.Fatalf("unexpected Commit executed")
-		}
-		act := m.actions[0]
-		m.actions = m.actions[1:]
-		if act.method != "Commit" {
-			m.t.Fatalf("unexpected Commit call, want action: %v", act)
-		}
-		if act.err != nil {
-			return nil, act.err
-		}
-	}
-	return &sppb.CommitResponse{CommitTimestamp: &pbt.Timestamp{Seconds: 1, Nanos: 2}}, nil
-}
-
-// Rollback is a placeholder for SpannerClient.Rollback.
-func (m *MockCloudSpannerClient) Rollback(c context.Context, r *sppb.RollbackRequest, opts ...grpc.CallOption) (*empty.Empty, error) {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	if !m.nice {
-		if err := m.injErr["Rollback"]; err != nil {
-			return nil, err
-		}
-		if len(m.actions) == 0 {
-			m.t.Fatalf("unexpected Rollback executed")
-		}
-		act := m.actions[0]
-		m.actions = m.actions[1:]
-		if act.method != "Rollback" {
-			m.t.Fatalf("unexpected Rollback call, want action: %v", act)
-		}
-		if act.err != nil {
-			return nil, act.err
-		}
-	}
-	return nil, nil
-}
diff --git a/vendor/cloud.google.com/go/spanner/internal/testutil/mockserver.go b/vendor/cloud.google.com/go/spanner/internal/testutil/mockserver.go
deleted file mode 100644
index 7a04e7f7f..000000000
--- a/vendor/cloud.google.com/go/spanner/internal/testutil/mockserver.go
+++ /dev/null
@@ -1,255 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package testutil
-
-import (
-	"encoding/binary"
-	"errors"
-	"fmt"
-	"io"
-	"net"
-	"testing"
-	"time"
-
-	"golang.org/x/net/context"
-
-	"github.com/golang/protobuf/ptypes/empty"
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-	pbt "github.com/golang/protobuf/ptypes/timestamp"
-
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
-)
-
-var (
-	// KvMeta is the Metadata for mocked KV table.
-	KvMeta = sppb.ResultSetMetadata{
-		RowType: &sppb.StructType{
-			Fields: []*sppb.StructType_Field{
-				{
-					Name: "Key",
-					Type: &sppb.Type{Code: sppb.TypeCode_STRING},
-				},
-				{
-					Name: "Value",
-					Type: &sppb.Type{Code: sppb.TypeCode_STRING},
-				},
-			},
-		},
-	}
-)
-
-// MockCtlMsg encapsulates PartialResultSet/error that might be sent to
-// client
-type MockCtlMsg struct {
-	// If ResumeToken == true, mock server will generate a row with
-	// resume token.
-	ResumeToken bool
-	// If Err != nil, mock server will return error in RPC response.
-	Err error
-}
-
-// MockCloudSpanner is a mock implementation of SpannerServer interface.
-// TODO: make MockCloudSpanner a full-fleged Cloud Spanner implementation.
-type MockCloudSpanner struct {
-	s      *grpc.Server
-	t      *testing.T
-	addr   string
-	msgs   chan MockCtlMsg
-	readTs time.Time
-	next   int
-}
-
-// Addr returns the listening address of mock server.
-func (m *MockCloudSpanner) Addr() string {
-	return m.addr
-}
-
-// AddMsg generates a new mocked row which can be received by client.
-func (m *MockCloudSpanner) AddMsg(err error, resumeToken bool) {
-	msg := MockCtlMsg{
-		ResumeToken: resumeToken,
-		Err:         err,
-	}
-	if err == io.EOF {
-		close(m.msgs)
-	} else {
-		m.msgs <- msg
-	}
-}
-
-// Done signals an end to a mocked stream.
-func (m *MockCloudSpanner) Done() {
-	close(m.msgs)
-}
-
-// CreateSession is a placeholder for SpannerServer.CreateSession.
-func (m *MockCloudSpanner) CreateSession(c context.Context, r *sppb.CreateSessionRequest) (*sppb.Session, error) {
-	m.t.Fatalf("CreateSession is unimplemented")
-	return nil, errors.New("Unimplemented")
-}
-
-// GetSession is a placeholder for SpannerServer.GetSession.
-func (m *MockCloudSpanner) GetSession(c context.Context, r *sppb.GetSessionRequest) (*sppb.Session, error) {
-	m.t.Fatalf("GetSession is unimplemented")
-	return nil, errors.New("Unimplemented")
-}
-
-// DeleteSession is a placeholder for SpannerServer.DeleteSession.
-func (m *MockCloudSpanner) DeleteSession(c context.Context, r *sppb.DeleteSessionRequest) (*empty.Empty, error) {
-	m.t.Fatalf("DeleteSession is unimplemented")
-	return nil, errors.New("Unimplemented")
-}
-
-// ExecuteSql is a placeholder for SpannerServer.ExecuteSql.
-func (m *MockCloudSpanner) ExecuteSql(c context.Context, r *sppb.ExecuteSqlRequest) (*sppb.ResultSet, error) {
-	m.t.Fatalf("ExecuteSql is unimplemented")
-	return nil, errors.New("Unimplemented")
-}
-
-// EncodeResumeToken return mock resume token encoding for an uint64 integer.
-func EncodeResumeToken(t uint64) []byte {
-	rt := make([]byte, 16)
-	binary.PutUvarint(rt, t)
-	return rt
-}
-
-// DecodeResumeToken decodes a mock resume token into an uint64 integer.
-func DecodeResumeToken(t []byte) (uint64, error) {
-	s, n := binary.Uvarint(t)
-	if n <= 0 {
-		return 0, fmt.Errorf("invalid resume token: %v", t)
-	}
-	return s, nil
-}
-
-// ExecuteStreamingSql is a mock implementation of SpannerServer.ExecuteStreamingSql.
-func (m *MockCloudSpanner) ExecuteStreamingSql(r *sppb.ExecuteSqlRequest, s sppb.Spanner_ExecuteStreamingSqlServer) error {
-	switch r.Sql {
-	case "SELECT * from t_unavailable":
-		return grpc.Errorf(codes.Unavailable, "mock table unavailable")
-	case "SELECT t.key key, t.value value FROM t_mock t":
-		if r.ResumeToken != nil {
-			s, err := DecodeResumeToken(r.ResumeToken)
-			if err != nil {
-				return err
-			}
-			m.next = int(s) + 1
-		}
-		for {
-			msg, more := <-m.msgs
-			if !more {
-				break
-			}
-			if msg.Err == nil {
-				var rt []byte
-				if msg.ResumeToken {
-					rt = EncodeResumeToken(uint64(m.next))
-				}
-				meta := KvMeta
-				meta.Transaction = &sppb.Transaction{
-					ReadTimestamp: &pbt.Timestamp{
-						Seconds: m.readTs.Unix(),
-						Nanos:   int32(m.readTs.Nanosecond()),
-					},
-				}
-				err := s.Send(&sppb.PartialResultSet{
-					Metadata: &meta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: fmt.Sprintf("foo-%02d", m.next)}},
-						{Kind: &proto3.Value_StringValue{StringValue: fmt.Sprintf("bar-%02d", m.next)}},
-					},
-					ResumeToken: rt,
-				})
-				m.next = m.next + 1
-				if err != nil {
-					return err
-				}
-				continue
-			}
-			return msg.Err
-		}
-		return nil
-	default:
-		return fmt.Errorf("unsupported SQL: %v", r.Sql)
-	}
-}
-
-// Read is a placeholder for SpannerServer.Read.
-func (m *MockCloudSpanner) Read(c context.Context, r *sppb.ReadRequest) (*sppb.ResultSet, error) {
-	m.t.Fatalf("Read is unimplemented")
-	return nil, errors.New("Unimplemented")
-}
-
-// StreamingRead is a placeholder for SpannerServer.StreamingRead.
-func (m *MockCloudSpanner) StreamingRead(r *sppb.ReadRequest, s sppb.Spanner_StreamingReadServer) error {
-	m.t.Fatalf("StreamingRead is unimplemented")
-	return errors.New("Unimplemented")
-}
-
-// BeginTransaction is a placeholder for SpannerServer.BeginTransaction.
-func (m *MockCloudSpanner) BeginTransaction(c context.Context, r *sppb.BeginTransactionRequest) (*sppb.Transaction, error) {
-	m.t.Fatalf("BeginTransaction is unimplemented")
-	return nil, errors.New("Unimplemented")
-}
-
-// Commit is a placeholder for SpannerServer.Commit.
-func (m *MockCloudSpanner) Commit(c context.Context, r *sppb.CommitRequest) (*sppb.CommitResponse, error) {
-	m.t.Fatalf("Commit is unimplemented")
-	return nil, errors.New("Unimplemented")
-}
-
-// Rollback is a placeholder for SpannerServer.Rollback.
-func (m *MockCloudSpanner) Rollback(c context.Context, r *sppb.RollbackRequest) (*empty.Empty, error) {
-	m.t.Fatalf("Rollback is unimplemented")
-	return nil, errors.New("Unimplemented")
-}
-
-// Serve runs a MockCloudSpanner listening on a random localhost address.
-func (m *MockCloudSpanner) Serve() {
-	m.s = grpc.NewServer()
-	if m.addr == "" {
-		m.addr = "localhost:0"
-	}
-	lis, err := net.Listen("tcp", m.addr)
-	if err != nil {
-		m.t.Fatalf("Failed to listen: %v", err)
-	}
-	go m.s.Serve(lis)
-	_, port, err := net.SplitHostPort(lis.Addr().String())
-	if err != nil {
-		m.t.Fatalf("Failed to parse listener address: %v", err)
-	}
-	sppb.RegisterSpannerServer(m.s, m)
-	m.addr = "localhost:" + port
-}
-
-// Stop terminates MockCloudSpanner and closes the serving port.
-func (m *MockCloudSpanner) Stop() {
-	m.s.Stop()
-}
-
-// NewMockCloudSpanner creates a new MockCloudSpanner instance.
-func NewMockCloudSpanner(t *testing.T, ts time.Time) *MockCloudSpanner {
-	mcs := &MockCloudSpanner{
-		t:      t,
-		msgs:   make(chan MockCtlMsg, 1000),
-		readTs: ts,
-	}
-	return mcs
-}
diff --git a/vendor/cloud.google.com/go/spanner/key.go b/vendor/cloud.google.com/go/spanner/key.go
deleted file mode 100644
index 1b780deff..000000000
--- a/vendor/cloud.google.com/go/spanner/key.go
+++ /dev/null
@@ -1,400 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"bytes"
-	"fmt"
-	"time"
-
-	"google.golang.org/grpc/codes"
-
-	"cloud.google.com/go/civil"
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-)
-
-// A Key can be either a Cloud Spanner row's primary key or a secondary index key.
-// It is essentially an interface{} array, which represents a set of Cloud Spanner
-// columns. A Key type has the following usages:
-//
-//     - Used as primary key which uniquely identifies a Cloud Spanner row.
-//     - Used as secondary index key which maps to a set of Cloud Spanner rows
-//       indexed under it.
-//     - Used as endpoints of primary key/secondary index ranges,
-//       see also the KeyRange type.
-//
-// Rows that are identified by the Key type are outputs of read operation or targets of
-// delete operation in a mutation. Note that for Insert/Update/InsertOrUpdate/Update
-// mutation types, although they don't require a primary key explicitly, the column list
-// provided must contain enough columns that can comprise a primary key.
-//
-// Keys are easy to construct.  For example, suppose you have a table with a
-// primary key of username and product ID.  To make a key for this table:
-//
-//	key := spanner.Key{"john", 16}
-//
-// See the description of Row and Mutation types for how Go types are
-// mapped to Cloud Spanner types. For convenience, Key type supports a wide range
-// of Go types:
-//     - int, int8, int16, int32, int64, and NullInt64 are mapped to Cloud Spanner's INT64 type.
-//     - uint8, uint16 and uint32 are also mapped to Cloud Spanner's INT64 type.
-//     - float32, float64, NullFloat64 are mapped to Cloud Spanner's FLOAT64 type.
-//     - bool and NullBool are mapped to Cloud Spanner's BOOL type.
-//     - []byte is mapped to Cloud Spanner's BYTES type.
-//     - string and NullString are mapped to Cloud Spanner's STRING type.
-//     - time.Time and NullTime are mapped to Cloud Spanner's TIMESTAMP type.
-//     - civil.Date and NullDate are mapped to Cloud Spanner's DATE type.
-type Key []interface{}
-
-// errInvdKeyPartType returns error for unsupported key part type.
-func errInvdKeyPartType(part interface{}) error {
-	return spannerErrorf(codes.InvalidArgument, "key part has unsupported type %T", part)
-}
-
-// keyPartValue converts a part of the Key (which is a valid Cloud Spanner type)
-// into a proto3.Value. Used for encoding Key type into protobuf.
-func keyPartValue(part interface{}) (pb *proto3.Value, err error) {
-	switch v := part.(type) {
-	case int:
-		pb, _, err = encodeValue(int64(v))
-	case int8:
-		pb, _, err = encodeValue(int64(v))
-	case int16:
-		pb, _, err = encodeValue(int64(v))
-	case int32:
-		pb, _, err = encodeValue(int64(v))
-	case uint8:
-		pb, _, err = encodeValue(int64(v))
-	case uint16:
-		pb, _, err = encodeValue(int64(v))
-	case uint32:
-		pb, _, err = encodeValue(int64(v))
-	case float32:
-		pb, _, err = encodeValue(float64(v))
-	case int64, float64, NullInt64, NullFloat64, bool, NullBool, []byte, string, NullString, time.Time, civil.Date, NullTime, NullDate:
-		pb, _, err = encodeValue(v)
-	default:
-		return nil, errInvdKeyPartType(v)
-	}
-	return pb, err
-}
-
-// proto converts a spanner.Key into a proto3.ListValue.
-func (key Key) proto() (*proto3.ListValue, error) {
-	lv := &proto3.ListValue{}
-	lv.Values = make([]*proto3.Value, 0, len(key))
-	for _, part := range key {
-		v, err := keyPartValue(part)
-		if err != nil {
-			return nil, err
-		}
-		lv.Values = append(lv.Values, v)
-	}
-	return lv, nil
-}
-
-// keySetProto lets a single Key act as a KeySet.
-func (key Key) keySetProto() (*sppb.KeySet, error) {
-	kp, err := key.proto()
-	if err != nil {
-		return nil, err
-	}
-	return &sppb.KeySet{Keys: []*proto3.ListValue{kp}}, nil
-}
-
-// String implements fmt.Stringer for Key. For string, []byte and NullString, it
-// prints the uninterpreted bytes of their contents, leaving caller with the
-// opportunity to escape the output.
-func (key Key) String() string {
-	b := &bytes.Buffer{}
-	fmt.Fprint(b, "(")
-	for i, part := range []interface{}(key) {
-		if i != 0 {
-			fmt.Fprint(b, ",")
-		}
-		switch v := part.(type) {
-		case int, int8, int16, int32, int64, uint, uint8, uint16, uint32, float32, float64, bool:
-			// Use %v to print numeric types and bool.
-			fmt.Fprintf(b, "%v", v)
-		case string:
-			fmt.Fprintf(b, "%q", v)
-		case []byte:
-			if v != nil {
-				fmt.Fprintf(b, "%q", v)
-			} else {
-				fmt.Fprint(b, "<null>")
-			}
-		case NullInt64, NullFloat64, NullBool, NullString, NullTime, NullDate:
-			// The above types implement fmt.Stringer.
-			fmt.Fprintf(b, "%s", v)
-		case civil.Date:
-			fmt.Fprintf(b, "%q", v)
-		case time.Time:
-			fmt.Fprintf(b, "%q", v.Format(time.RFC3339Nano))
-		default:
-			fmt.Fprintf(b, "%v", v)
-		}
-	}
-	fmt.Fprint(b, ")")
-	return b.String()
-}
-
-// AsPrefix returns a KeyRange for all keys where k is the prefix.
-func (k Key) AsPrefix() KeyRange {
-	return KeyRange{
-		Start: k,
-		End:   k,
-		Kind:  ClosedClosed,
-	}
-}
-
-// KeyRangeKind describes the kind of interval represented by a KeyRange:
-// whether it is open or closed on the left and right.
-type KeyRangeKind int
-
-const (
-	// ClosedOpen is closed on the left and open on the right: the Start
-	// key is included, the End key is excluded.
-	ClosedOpen KeyRangeKind = iota
-
-	// ClosedClosed is closed on the left and the right: both keys are included.
-	ClosedClosed
-
-	// OpenClosed is open on the left and closed on the right: the Start
-	// key is excluded, the End key is included.
-	OpenClosed
-
-	// OpenOpen is open on the left and the right: neither key is included.
-	OpenOpen
-)
-
-// A KeyRange represents a range of rows in a table or index.
-//
-// A range has a Start key and an End key.  IncludeStart and IncludeEnd
-// indicate whether the Start and End keys are included in the range.
-//
-// For example, consider the following table definition:
-//
-//	CREATE TABLE UserEvents (
-//	  UserName STRING(MAX),
-//	  EventDate STRING(10),
-//	) PRIMARY KEY(UserName, EventDate);
-//
-// The following keys name rows in this table:
-//
-//	spanner.Key{"Bob", "2014-09-23"}
-//	spanner.Key{"Alfred", "2015-06-12"}
-//
-// Since the UserEvents table's PRIMARY KEY clause names two columns, each
-// UserEvents key has two elements; the first is the UserName, and the second
-// is the EventDate.
-//
-// Key ranges with multiple components are interpreted lexicographically by
-// component using the table or index key's declared sort order. For example,
-// the following range returns all events for user "Bob" that occurred in the
-// year 2015:
-//
-// 	spanner.KeyRange{
-//		Start: spanner.Key{"Bob", "2015-01-01"},
-//		End:   spanner.Key{"Bob", "2015-12-31"},
-//		Kind:  ClosedClosed,
-//	}
-//
-// Start and end keys can omit trailing key components. This affects the
-// inclusion and exclusion of rows that exactly match the provided key
-// components: if IncludeStart is true, then rows that exactly match the
-// provided components of the Start key are included; if IncludeStart is false
-// then rows that exactly match are not included.  IncludeEnd and End key
-// behave in the same fashion.
-//
-// For example, the following range includes all events for "Bob" that occurred
-// during and after the year 2000:
-//
-//	spanner.KeyRange{
-//		Start: spanner.Key{"Bob", "2000-01-01"},
-//		End:   spanner.Key{"Bob"},
-//		Kind:  ClosedClosed,
-//	}
-//
-// The next example retrieves all events for "Bob":
-//
-//	spanner.Key{"Bob"}.AsPrefix()
-//
-// To retrieve events before the year 2000:
-//
-//	spanner.KeyRange{
-//		Start: spanner.Key{"Bob"},
-//		End:   spanner.Key{"Bob", "2000-01-01"},
-//		Kind:  ClosedOpen,
-//	}
-//
-// Although we specified a Kind for this KeyRange, we didn't need to, because
-// the default is ClosedOpen. In later examples we'll omit Kind if it is
-// ClosedOpen.
-//
-// The following range includes all rows in a table or under a
-// index:
-//
-//	spanner.AllKeys()
-//
-// This range returns all users whose UserName begins with any
-// character from A to C:
-//
-//	spanner.KeyRange{
-//		Start: spanner.Key{"A"},
-//		End:   spanner.Key{"D"},
-//	}
-//
-// This range returns all users whose UserName begins with B:
-//
-//	spanner.KeyRange{
-//		Start: spanner.Key{"B"},
-//		End:   spanner.Key{"C"},
-//	}
-//
-// Key ranges honor column sort order. For example, suppose a table is defined
-// as follows:
-//
-//	CREATE TABLE DescendingSortedTable {
-//	  Key INT64,
-//	  ...
-//	) PRIMARY KEY(Key DESC);
-//
-// The following range retrieves all rows with key values between 1 and 100
-// inclusive:
-//
-//	spanner.KeyRange{
-//		Start: spanner.Key{100},
-//		End:   spanner.Key{1},
-//		Kind:  ClosedClosed,
-//	}
-//
-// Note that 100 is passed as the start, and 1 is passed as the end, because
-// Key is a descending column in the schema.
-type KeyRange struct {
-	// Start specifies the left boundary of the key range; End specifies
-	// the right boundary of the key range.
-	Start, End Key
-
-	// Kind describes whether the boundaries of the key range include
-	// their keys.
-	Kind KeyRangeKind
-}
-
-// String implements fmt.Stringer for KeyRange type.
-func (r KeyRange) String() string {
-	var left, right string
-	switch r.Kind {
-	case ClosedClosed:
-		left, right = "[", "]"
-	case ClosedOpen:
-		left, right = "[", ")"
-	case OpenClosed:
-		left, right = "(", "]"
-	case OpenOpen:
-		left, right = "(", ")"
-	default:
-		left, right = "?", "?"
-	}
-	return fmt.Sprintf("%s%s,%s%s", left, r.Start, r.End, right)
-}
-
-// proto converts KeyRange into sppb.KeyRange.
-func (r KeyRange) proto() (*sppb.KeyRange, error) {
-	var err error
-	var start, end *proto3.ListValue
-	pb := &sppb.KeyRange{}
-	if start, err = r.Start.proto(); err != nil {
-		return nil, err
-	}
-	if end, err = r.End.proto(); err != nil {
-		return nil, err
-	}
-	if r.Kind == ClosedClosed || r.Kind == ClosedOpen {
-		pb.StartKeyType = &sppb.KeyRange_StartClosed{StartClosed: start}
-	} else {
-		pb.StartKeyType = &sppb.KeyRange_StartOpen{StartOpen: start}
-	}
-	if r.Kind == ClosedClosed || r.Kind == OpenClosed {
-		pb.EndKeyType = &sppb.KeyRange_EndClosed{EndClosed: end}
-	} else {
-		pb.EndKeyType = &sppb.KeyRange_EndOpen{EndOpen: end}
-	}
-	return pb, nil
-}
-
-// keySetProto lets a KeyRange act as a KeySet.
-func (r KeyRange) keySetProto() (*sppb.KeySet, error) {
-	rp, err := r.proto()
-	if err != nil {
-		return nil, err
-	}
-	return &sppb.KeySet{Ranges: []*sppb.KeyRange{rp}}, nil
-}
-
-// A KeySet defines a collection of Cloud Spanner keys and/or key ranges. All the
-// keys are expected to be in the same table or index. The keys need not be sorted in
-// any particular way.
-//
-// An individual Key can act as a KeySet, as can a KeyRange. Use the KeySets function
-// to create a KeySet consisting of multiple Keys and KeyRanges. To obtain an empty
-// KeySet, call KeySets with no arguments.
-//
-// If the same key is specified multiple times in the set (for example if two
-// ranges, two keys, or a key and a range overlap), the Cloud Spanner backend behaves
-// as if the key were only specified once.
-type KeySet interface {
-	keySetProto() (*sppb.KeySet, error)
-}
-
-// AllKeys returns a KeySet that represents all Keys of a table or a index.
-func AllKeys() KeySet {
-	return all{}
-}
-
-type all struct{}
-
-func (all) keySetProto() (*sppb.KeySet, error) {
-	return &sppb.KeySet{All: true}, nil
-}
-
-// KeySets returns the union of the KeySets. If any of the KeySets is AllKeys, then
-// the resulting KeySet will be equivalent to AllKeys.
-func KeySets(keySets ...KeySet) KeySet {
-	u := make(union, len(keySets))
-	copy(u, keySets)
-	return u
-}
-
-type union []KeySet
-
-func (u union) keySetProto() (*sppb.KeySet, error) {
-	upb := &sppb.KeySet{}
-	for _, ks := range u {
-		pb, err := ks.keySetProto()
-		if err != nil {
-			return nil, err
-		}
-		if pb.All {
-			return pb, nil
-		}
-		upb.Keys = append(upb.Keys, pb.Keys...)
-		upb.Ranges = append(upb.Ranges, pb.Ranges...)
-	}
-	return upb, nil
-}
diff --git a/vendor/cloud.google.com/go/spanner/key_test.go b/vendor/cloud.google.com/go/spanner/key_test.go
deleted file mode 100644
index e552e8647..000000000
--- a/vendor/cloud.google.com/go/spanner/key_test.go
+++ /dev/null
@@ -1,373 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"reflect"
-	"testing"
-	"time"
-
-	"cloud.google.com/go/civil"
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-)
-
-// Test Key.String() and Key.proto().
-func TestKey(t *testing.T) {
-	tm, _ := time.Parse(time.RFC3339Nano, "2016-11-15T15:04:05.999999999Z")
-	dt, _ := civil.ParseDate("2016-11-15")
-	for _, test := range []struct {
-		k         Key
-		wantProto *proto3.ListValue
-		wantStr   string
-	}{
-		{
-			k:         Key{int(1)},
-			wantProto: listValueProto(stringProto("1")),
-			wantStr:   "(1)",
-		},
-		{
-			k:         Key{int8(1)},
-			wantProto: listValueProto(stringProto("1")),
-			wantStr:   "(1)",
-		},
-		{
-			k:         Key{int16(1)},
-			wantProto: listValueProto(stringProto("1")),
-			wantStr:   "(1)",
-		},
-		{
-			k:         Key{int32(1)},
-			wantProto: listValueProto(stringProto("1")),
-			wantStr:   "(1)",
-		},
-		{
-			k:         Key{int64(1)},
-			wantProto: listValueProto(stringProto("1")),
-			wantStr:   "(1)",
-		},
-		{
-			k:         Key{uint8(1)},
-			wantProto: listValueProto(stringProto("1")),
-			wantStr:   "(1)",
-		},
-		{
-			k:         Key{uint16(1)},
-			wantProto: listValueProto(stringProto("1")),
-			wantStr:   "(1)",
-		},
-		{
-			k:         Key{uint32(1)},
-			wantProto: listValueProto(stringProto("1")),
-			wantStr:   "(1)",
-		},
-		{
-			k:         Key{true},
-			wantProto: listValueProto(boolProto(true)),
-			wantStr:   "(true)",
-		},
-		{
-			k:         Key{float32(1.5)},
-			wantProto: listValueProto(floatProto(1.5)),
-			wantStr:   "(1.5)",
-		},
-		{
-			k:         Key{float64(1.5)},
-			wantProto: listValueProto(floatProto(1.5)),
-			wantStr:   "(1.5)",
-		},
-		{
-			k:         Key{"value"},
-			wantProto: listValueProto(stringProto("value")),
-			wantStr:   `("value")`,
-		},
-		{
-			k:         Key{[]byte(nil)},
-			wantProto: listValueProto(nullProto()),
-			wantStr:   "(<null>)",
-		},
-		{
-			k:         Key{[]byte{}},
-			wantProto: listValueProto(stringProto("")),
-			wantStr:   `("")`,
-		},
-		{
-			k:         Key{tm},
-			wantProto: listValueProto(stringProto("2016-11-15T15:04:05.999999999Z")),
-			wantStr:   `("2016-11-15T15:04:05.999999999Z")`,
-		},
-		{k: Key{dt},
-			wantProto: listValueProto(stringProto("2016-11-15")),
-			wantStr:   `("2016-11-15")`,
-		},
-		{
-			k:         Key{[]byte("value")},
-			wantProto: listValueProto(bytesProto([]byte("value"))),
-			wantStr:   `("value")`,
-		},
-		{
-			k:         Key{NullInt64{1, true}},
-			wantProto: listValueProto(stringProto("1")),
-			wantStr:   "(1)",
-		},
-		{
-			k:         Key{NullInt64{2, false}},
-			wantProto: listValueProto(nullProto()),
-			wantStr:   "(<null>)",
-		},
-		{
-			k:         Key{NullFloat64{1.5, true}},
-			wantProto: listValueProto(floatProto(1.5)),
-			wantStr:   "(1.5)",
-		},
-		{
-			k:         Key{NullFloat64{2.0, false}},
-			wantProto: listValueProto(nullProto()),
-			wantStr:   "(<null>)",
-		},
-		{
-			k:         Key{NullBool{true, true}},
-			wantProto: listValueProto(boolProto(true)),
-			wantStr:   "(true)",
-		},
-		{
-			k:         Key{NullBool{true, false}},
-			wantProto: listValueProto(nullProto()),
-			wantStr:   "(<null>)",
-		},
-		{
-			k:         Key{NullString{"value", true}},
-			wantProto: listValueProto(stringProto("value")),
-			wantStr:   `("value")`,
-		},
-		{
-			k:         Key{NullString{"value", false}},
-			wantProto: listValueProto(nullProto()),
-			wantStr:   "(<null>)",
-		},
-		{
-			k:         Key{NullTime{tm, true}},
-			wantProto: listValueProto(timeProto(tm)),
-			wantStr:   `("2016-11-15T15:04:05.999999999Z")`,
-		},
-
-		{
-			k:         Key{NullTime{time.Now(), false}},
-			wantProto: listValueProto(nullProto()),
-			wantStr:   "(<null>)",
-		},
-		{
-			k:         Key{NullDate{dt, true}},
-			wantProto: listValueProto(dateProto(dt)),
-			wantStr:   `("2016-11-15")`,
-		},
-		{
-			k:         Key{NullDate{civil.Date{}, false}},
-			wantProto: listValueProto(nullProto()),
-			wantStr:   "(<null>)",
-		},
-		{
-			k:         Key{int(1), NullString{"value", false}, "value", 1.5, true},
-			wantProto: listValueProto(stringProto("1"), nullProto(), stringProto("value"), floatProto(1.5), boolProto(true)),
-			wantStr:   `(1,<null>,"value",1.5,true)`,
-		},
-	} {
-		if got := test.k.String(); got != test.wantStr {
-			t.Errorf("%v.String() = %v, want %v", test.k, got, test.wantStr)
-		}
-		gotProto, err := test.k.proto()
-		if err != nil {
-			t.Errorf("%v.proto() returns error %v; want nil error", test.k, err)
-		}
-		if !reflect.DeepEqual(gotProto, test.wantProto) {
-			t.Errorf("%v.proto() = \n%v\nwant:\n%v", test.k, gotProto, test.wantProto)
-		}
-	}
-}
-
-// Test KeyRange.String() and KeyRange.proto().
-func TestKeyRange(t *testing.T) {
-	for _, test := range []struct {
-		kr        KeyRange
-		wantProto *sppb.KeyRange
-		wantStr   string
-	}{
-		{
-			kr: KeyRange{Key{"A"}, Key{"D"}, OpenOpen},
-			wantProto: &sppb.KeyRange{
-				&sppb.KeyRange_StartOpen{listValueProto(stringProto("A"))},
-				&sppb.KeyRange_EndOpen{listValueProto(stringProto("D"))},
-			},
-			wantStr: `(("A"),("D"))`,
-		},
-		{
-			kr: KeyRange{Key{1}, Key{10}, OpenClosed},
-			wantProto: &sppb.KeyRange{
-				&sppb.KeyRange_StartOpen{listValueProto(stringProto("1"))},
-				&sppb.KeyRange_EndClosed{listValueProto(stringProto("10"))},
-			},
-			wantStr: "((1),(10)]",
-		},
-		{
-			kr: KeyRange{Key{1.5, 2.1, 0.2}, Key{1.9, 0.7}, ClosedOpen},
-			wantProto: &sppb.KeyRange{
-				&sppb.KeyRange_StartClosed{listValueProto(floatProto(1.5), floatProto(2.1), floatProto(0.2))},
-				&sppb.KeyRange_EndOpen{listValueProto(floatProto(1.9), floatProto(0.7))},
-			},
-			wantStr: "[(1.5,2.1,0.2),(1.9,0.7))",
-		},
-		{
-			kr: KeyRange{Key{NullInt64{1, true}}, Key{10}, ClosedClosed},
-			wantProto: &sppb.KeyRange{
-				&sppb.KeyRange_StartClosed{listValueProto(stringProto("1"))},
-				&sppb.KeyRange_EndClosed{listValueProto(stringProto("10"))},
-			},
-			wantStr: "[(1),(10)]",
-		},
-	} {
-		if got := test.kr.String(); got != test.wantStr {
-			t.Errorf("%v.String() = %v, want %v", test.kr, got, test.wantStr)
-		}
-		gotProto, err := test.kr.proto()
-		if err != nil {
-			t.Errorf("%v.proto() returns error %v; want nil error", test.kr, err)
-		}
-		if !reflect.DeepEqual(gotProto, test.wantProto) {
-			t.Errorf("%v.proto() = \n%v\nwant:\n%v", test.kr, gotProto.String(), test.wantProto.String())
-		}
-	}
-}
-
-func TestPrefixRange(t *testing.T) {
-	got := Key{1}.AsPrefix()
-	want := KeyRange{Start: Key{1}, End: Key{1}, Kind: ClosedClosed}
-	if !reflect.DeepEqual(got, want) {
-		t.Errorf("got %v, want %v", got, want)
-	}
-}
-
-func TestKeySets(t *testing.T) {
-	int1 := intProto(1)
-	int2 := intProto(2)
-	int3 := intProto(3)
-	int4 := intProto(4)
-	for i, test := range []struct {
-		ks        KeySet
-		wantProto *sppb.KeySet
-	}{
-		{
-			KeySets(),
-			&sppb.KeySet{},
-		},
-		{
-			Key{4},
-			&sppb.KeySet{
-				Keys: []*proto3.ListValue{listValueProto(int4)},
-			},
-		},
-		{
-			AllKeys(),
-			&sppb.KeySet{All: true},
-		},
-		{
-			KeySets(Key{1, 2}, Key{3, 4}),
-			&sppb.KeySet{
-				Keys: []*proto3.ListValue{
-					listValueProto(int1, int2),
-					listValueProto(int3, int4),
-				},
-			},
-		},
-		{
-			KeyRange{Key{1}, Key{2}, ClosedOpen},
-			&sppb.KeySet{Ranges: []*sppb.KeyRange{
-				&sppb.KeyRange{
-					&sppb.KeyRange_StartClosed{listValueProto(int1)},
-					&sppb.KeyRange_EndOpen{listValueProto(int2)},
-				},
-			}},
-		},
-		{
-			Key{2}.AsPrefix(),
-			&sppb.KeySet{Ranges: []*sppb.KeyRange{
-				&sppb.KeyRange{
-					&sppb.KeyRange_StartClosed{listValueProto(int2)},
-					&sppb.KeyRange_EndClosed{listValueProto(int2)},
-				},
-			}},
-		},
-		{
-			KeySets(
-				KeyRange{Key{1}, Key{2}, ClosedClosed},
-				KeyRange{Key{3}, Key{4}, OpenClosed},
-			),
-			&sppb.KeySet{
-				Ranges: []*sppb.KeyRange{
-					&sppb.KeyRange{
-						&sppb.KeyRange_StartClosed{listValueProto(int1)},
-						&sppb.KeyRange_EndClosed{listValueProto(int2)},
-					},
-					&sppb.KeyRange{
-						&sppb.KeyRange_StartOpen{listValueProto(int3)},
-						&sppb.KeyRange_EndClosed{listValueProto(int4)},
-					},
-				},
-			},
-		},
-		{
-			KeySets(
-				Key{1},
-				KeyRange{Key{2}, Key{3}, ClosedClosed},
-				KeyRange{Key{4}, Key{5}, OpenClosed},
-				KeySets(),
-				Key{6}),
-			&sppb.KeySet{
-				Keys: []*proto3.ListValue{
-					listValueProto(int1),
-					listValueProto(intProto(6)),
-				},
-				Ranges: []*sppb.KeyRange{
-					&sppb.KeyRange{
-						&sppb.KeyRange_StartClosed{listValueProto(int2)},
-						&sppb.KeyRange_EndClosed{listValueProto(int3)},
-					},
-					&sppb.KeyRange{
-						&sppb.KeyRange_StartOpen{listValueProto(int4)},
-						&sppb.KeyRange_EndClosed{listValueProto(intProto(5))},
-					},
-				},
-			},
-		},
-		{
-			KeySets(
-				Key{1},
-				KeyRange{Key{2}, Key{3}, ClosedClosed},
-				AllKeys(),
-				KeyRange{Key{4}, Key{5}, OpenClosed},
-				Key{6}),
-			&sppb.KeySet{All: true},
-		},
-	} {
-		gotProto, err := test.ks.keySetProto()
-		if err != nil {
-			t.Errorf("#%d: %v.proto() returns error %v; want nil error", i, test.ks, err)
-		}
-		if !reflect.DeepEqual(gotProto, test.wantProto) {
-			t.Errorf("#%d: %v.proto() = \n%v\nwant:\n%v", i, test.ks, gotProto.String(), test.wantProto.String())
-		}
-	}
-}
diff --git a/vendor/cloud.google.com/go/spanner/mutation.go b/vendor/cloud.google.com/go/spanner/mutation.go
deleted file mode 100644
index 81f25746d..000000000
--- a/vendor/cloud.google.com/go/spanner/mutation.go
+++ /dev/null
@@ -1,431 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"reflect"
-
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-	"google.golang.org/grpc/codes"
-)
-
-// op is the mutation operation.
-type op int
-
-const (
-	// opDelete removes a row from a table.  Succeeds whether or not the
-	// key was present.
-	opDelete op = iota
-	// opInsert inserts a row into a table.  If the row already exists, the
-	// write or transaction fails.
-	opInsert
-	// opInsertOrUpdate inserts a row into a table. If the row already
-	// exists, it updates it instead.  Any column values not explicitly
-	// written are preserved.
-	opInsertOrUpdate
-	// opReplace inserts a row into a table, deleting any existing row.
-	// Unlike InsertOrUpdate, this means any values not explicitly written
-	// become NULL.
-	opReplace
-	// opUpdate updates a row in a table.  If the row does not already
-	// exist, the write or transaction fails.
-	opUpdate
-)
-
-// A Mutation describes a modification to one or more Cloud Spanner rows.  The
-// mutation represents an insert, update, delete, etc on a table.
-//
-// Many mutations can be applied in a single atomic commit. For purposes of
-// constraint checking (such as foreign key constraints), the operations can be
-// viewed as applying in same order as the mutations are supplied in (so that
-// e.g., a row and its logical "child" can be inserted in the same commit).
-//
-//	- The Apply function applies series of mutations.
-//	- A ReadWriteTransaction applies a series of mutations as part of an
-//	  atomic read-modify-write operation.
-// Example:
-//
-//	m := spanner.Insert("User",
-//		[]string{"user_id", "profile"},
-//		[]interface{}{UserID, profile})
-//	_, err := client.Apply(ctx, []*spanner.Mutation{m})
-//
-// In this example, we insert a new row into the User table. The primary key
-// for the new row is UserID (presuming that "user_id" has been declared as the
-// primary key of the "User" table).
-//
-// Updating a row
-//
-// Changing the values of columns in an existing row is very similar to
-// inserting a new row:
-//
-//	m := spanner.Update("User",
-//		[]string{"user_id", "profile"},
-//		[]interface{}{UserID, profile})
-//	_, err := client.Apply(ctx, []*spanner.Mutation{m})
-//
-// Deleting a row
-//
-// To delete a row, use spanner.Delete:
-//
-//	m := spanner.Delete("User", spanner.Key{UserId})
-//	_, err := client.Apply(ctx, []*spanner.Mutation{m})
-//
-// spanner.Delete accepts a KeySet, so you can also pass in a KeyRange, or use the
-// spanner.KeySets function to build any combination of Keys and KeyRanges.
-//
-// Note that deleting a row in a table may also delete rows from other tables
-// if cascading deletes are specified in those tables' schemas. Delete does
-// nothing if the named row does not exist (does not yield an error).
-//
-// Deleting a field
-//
-// To delete/clear a field within a row, use spanner.Update with the value nil:
-//
-//	m := spanner.Update("User",
-//		[]string{"user_id", "profile"},
-//		[]interface{}{UserID, nil})
-//	_, err := client.Apply(ctx, []*spanner.Mutation{m})
-//
-// The valid Go types and their corresponding Cloud Spanner types that can be
-// used in the Insert/Update/InsertOrUpdate functions are:
-//
-//     string, NullString - STRING
-//     []string, []NullString - STRING ARRAY
-//     []byte - BYTES
-//     [][]byte - BYTES ARRAY
-//     int, int64, NullInt64 - INT64
-//     []int, []int64, []NullInt64 - INT64 ARRAY
-//     bool, NullBool - BOOL
-//     []bool, []NullBool - BOOL ARRAY
-//     float64, NullFloat64 - FLOAT64
-//     []float64, []NullFloat64 - FLOAT64 ARRAY
-//     time.Time, NullTime - TIMESTAMP
-//     []time.Time, []NullTime - TIMESTAMP ARRAY
-//     Date, NullDate - DATE
-//     []Date, []NullDate - DATE ARRAY
-//
-// To compare two Mutations for testing purposes, use reflect.DeepEqual.
-type Mutation struct {
-	// op is the operation type of the mutation.
-	// See documentation for spanner.op for more details.
-	op op
-	// Table is the name of the taget table to be modified.
-	table string
-	// keySet is a set of primary keys that names the rows
-	// in a delete operation.
-	keySet KeySet
-	// columns names the set of columns that are going to be
-	// modified by Insert, InsertOrUpdate, Replace or Update
-	// operations.
-	columns []string
-	// values specifies the new values for the target columns
-	// named by Columns.
-	values []interface{}
-}
-
-// mapToMutationParams converts Go map into mutation parameters.
-func mapToMutationParams(in map[string]interface{}) ([]string, []interface{}) {
-	cols := []string{}
-	vals := []interface{}{}
-	for k, v := range in {
-		cols = append(cols, k)
-		vals = append(vals, v)
-	}
-	return cols, vals
-}
-
-// errNotStruct returns error for not getting a go struct type.
-func errNotStruct(in interface{}) error {
-	return spannerErrorf(codes.InvalidArgument, "%T is not a go struct type", in)
-}
-
-// structToMutationParams converts Go struct into mutation parameters.
-// If the input is not a valid Go struct type, structToMutationParams
-// returns error.
-func structToMutationParams(in interface{}) ([]string, []interface{}, error) {
-	if in == nil {
-		return nil, nil, errNotStruct(in)
-	}
-	v := reflect.ValueOf(in)
-	t := v.Type()
-	if t.Kind() == reflect.Ptr && t.Elem().Kind() == reflect.Struct {
-		// t is a pointer to a struct.
-		if v.IsNil() {
-			// Return empty results.
-			return nil, nil, nil
-		}
-		// Get the struct value that in points to.
-		v = v.Elem()
-		t = t.Elem()
-	}
-	if t.Kind() != reflect.Struct {
-		return nil, nil, errNotStruct(in)
-	}
-	fields, err := fieldCache.Fields(t)
-	if err != nil {
-		return nil, nil, toSpannerError(err)
-	}
-	var cols []string
-	var vals []interface{}
-	for _, f := range fields {
-		cols = append(cols, f.Name)
-		vals = append(vals, v.FieldByIndex(f.Index).Interface())
-	}
-	return cols, vals, nil
-}
-
-// Insert returns a Mutation to insert a row into a table. If the row already
-// exists, the write or transaction fails.
-func Insert(table string, cols []string, vals []interface{}) *Mutation {
-	return &Mutation{
-		op:      opInsert,
-		table:   table,
-		columns: cols,
-		values:  vals,
-	}
-}
-
-// InsertMap returns a Mutation to insert a row into a table, specified by
-// a map of column name to value. If the row already exists, the write or
-// transaction fails.
-func InsertMap(table string, in map[string]interface{}) *Mutation {
-	cols, vals := mapToMutationParams(in)
-	return Insert(table, cols, vals)
-}
-
-// InsertStruct returns a Mutation to insert a row into a table, specified by
-// a Go struct.  If the row already exists, the write or transaction fails.
-//
-// The in argument must be a struct or a pointer to a struct. Its exported
-// fields specify the column names and values. Use a field tag like "spanner:name"
-// to provide an alternative column name, or use "spanner:-" to ignore the field.
-func InsertStruct(table string, in interface{}) (*Mutation, error) {
-	cols, vals, err := structToMutationParams(in)
-	if err != nil {
-		return nil, err
-	}
-	return Insert(table, cols, vals), nil
-}
-
-// Update returns a Mutation to update a row in a table. If the row does not
-// already exist, the write or transaction fails.
-func Update(table string, cols []string, vals []interface{}) *Mutation {
-	return &Mutation{
-		op:      opUpdate,
-		table:   table,
-		columns: cols,
-		values:  vals,
-	}
-}
-
-// UpdateMap returns a Mutation to update a row in a table, specified by
-// a map of column to value. If the row does not already exist, the write or
-// transaction fails.
-func UpdateMap(table string, in map[string]interface{}) *Mutation {
-	cols, vals := mapToMutationParams(in)
-	return Update(table, cols, vals)
-}
-
-// UpdateStruct returns a Mutation to update a row in a table, specified by a Go
-// struct. If the row does not already exist, the write or transaction fails.
-func UpdateStruct(table string, in interface{}) (*Mutation, error) {
-	cols, vals, err := structToMutationParams(in)
-	if err != nil {
-		return nil, err
-	}
-	return Update(table, cols, vals), nil
-}
-
-// InsertOrUpdate returns a Mutation to insert a row into a table. If the row
-// already exists, it updates it instead. Any column values not explicitly
-// written are preserved.
-//
-// For a similar example, See Update.
-func InsertOrUpdate(table string, cols []string, vals []interface{}) *Mutation {
-	return &Mutation{
-		op:      opInsertOrUpdate,
-		table:   table,
-		columns: cols,
-		values:  vals,
-	}
-}
-
-// InsertOrUpdateMap returns a Mutation to insert a row into a table,
-// specified by a map of column to value. If the row already exists, it
-// updates it instead. Any column values not explicitly written are preserved.
-//
-// For a similar example, See UpdateMap.
-func InsertOrUpdateMap(table string, in map[string]interface{}) *Mutation {
-	cols, vals := mapToMutationParams(in)
-	return InsertOrUpdate(table, cols, vals)
-}
-
-// InsertOrUpdateStruct returns a Mutation to insert a row into a table,
-// specified by a Go struct. If the row already exists, it updates it instead.
-// Any column values not explicitly written are preserved.
-//
-// The in argument must be a struct or a pointer to a struct. Its exported
-// fields specify the column names and values. Use a field tag like "spanner:name"
-// to provide an alternative column name, or use "spanner:-" to ignore the field.
-//
-// For a similar example, See UpdateStruct.
-func InsertOrUpdateStruct(table string, in interface{}) (*Mutation, error) {
-	cols, vals, err := structToMutationParams(in)
-	if err != nil {
-		return nil, err
-	}
-	return InsertOrUpdate(table, cols, vals), nil
-}
-
-// Replace returns a Mutation to insert a row into a table, deleting any
-// existing row. Unlike InsertOrUpdate, this means any values not explicitly
-// written become NULL.
-//
-// For a similar example, See Update.
-func Replace(table string, cols []string, vals []interface{}) *Mutation {
-	return &Mutation{
-		op:      opReplace,
-		table:   table,
-		columns: cols,
-		values:  vals,
-	}
-}
-
-// ReplaceMap returns a Mutation to insert a row into a table, deleting any
-// existing row. Unlike InsertOrUpdateMap, this means any values not explicitly
-// written become NULL.  The row is specified by a map of column to value.
-//
-// For a similar example, See UpdateMap.
-func ReplaceMap(table string, in map[string]interface{}) *Mutation {
-	cols, vals := mapToMutationParams(in)
-	return Replace(table, cols, vals)
-}
-
-// ReplaceStruct returns a Mutation to insert a row into a table, deleting any
-// existing row. Unlike InsertOrUpdateMap, this means any values not explicitly
-// written become NULL.  The row is specified by a Go struct.
-//
-// The in argument must be a struct or a pointer to a struct. Its exported
-// fields specify the column names and values. Use a field tag like "spanner:name"
-// to provide an alternative column name, or use "spanner:-" to ignore the field.
-//
-// For a similar example, See UpdateStruct.
-func ReplaceStruct(table string, in interface{}) (*Mutation, error) {
-	cols, vals, err := structToMutationParams(in)
-	if err != nil {
-		return nil, err
-	}
-	return Replace(table, cols, vals), nil
-}
-
-// Delete removes the rows described by the KeySet from the table. It succeeds
-// whether or not the keys were present.
-func Delete(table string, ks KeySet) *Mutation {
-	return &Mutation{
-		op:     opDelete,
-		table:  table,
-		keySet: ks,
-	}
-}
-
-// prepareWrite generates sppb.Mutation_Write from table name, column names
-// and new column values.
-func prepareWrite(table string, columns []string, vals []interface{}) (*sppb.Mutation_Write, error) {
-	v, err := encodeValueArray(vals)
-	if err != nil {
-		return nil, err
-	}
-	return &sppb.Mutation_Write{
-		Table:   table,
-		Columns: columns,
-		Values:  []*proto3.ListValue{v},
-	}, nil
-}
-
-// errInvdMutationOp returns error for unrecognized mutation operation.
-func errInvdMutationOp(m Mutation) error {
-	return spannerErrorf(codes.InvalidArgument, "Unknown op type: %d", m.op)
-}
-
-// proto converts spanner.Mutation to sppb.Mutation, in preparation to send
-// RPCs.
-func (m Mutation) proto() (*sppb.Mutation, error) {
-	var pb *sppb.Mutation
-	switch m.op {
-	case opDelete:
-		var kp *sppb.KeySet
-		if m.keySet != nil {
-			var err error
-			kp, err = m.keySet.keySetProto()
-			if err != nil {
-				return nil, err
-			}
-		}
-		pb = &sppb.Mutation{
-			Operation: &sppb.Mutation_Delete_{
-				Delete: &sppb.Mutation_Delete{
-					Table:  m.table,
-					KeySet: kp,
-				},
-			},
-		}
-	case opInsert:
-		w, err := prepareWrite(m.table, m.columns, m.values)
-		if err != nil {
-			return nil, err
-		}
-		pb = &sppb.Mutation{Operation: &sppb.Mutation_Insert{Insert: w}}
-	case opInsertOrUpdate:
-		w, err := prepareWrite(m.table, m.columns, m.values)
-		if err != nil {
-			return nil, err
-		}
-		pb = &sppb.Mutation{Operation: &sppb.Mutation_InsertOrUpdate{InsertOrUpdate: w}}
-	case opReplace:
-		w, err := prepareWrite(m.table, m.columns, m.values)
-		if err != nil {
-			return nil, err
-		}
-		pb = &sppb.Mutation{Operation: &sppb.Mutation_Replace{Replace: w}}
-	case opUpdate:
-		w, err := prepareWrite(m.table, m.columns, m.values)
-		if err != nil {
-			return nil, err
-		}
-		pb = &sppb.Mutation{Operation: &sppb.Mutation_Update{Update: w}}
-	default:
-		return nil, errInvdMutationOp(m)
-	}
-	return pb, nil
-}
-
-// mutationsProto turns a spanner.Mutation array into a sppb.Mutation array,
-// it is convenient for sending batch mutations to Cloud Spanner.
-func mutationsProto(ms []*Mutation) ([]*sppb.Mutation, error) {
-	l := make([]*sppb.Mutation, 0, len(ms))
-	for _, m := range ms {
-		pb, err := m.proto()
-		if err != nil {
-			return nil, err
-		}
-		l = append(l, pb)
-	}
-	return l, nil
-}
diff --git a/vendor/cloud.google.com/go/spanner/mutation_test.go b/vendor/cloud.google.com/go/spanner/mutation_test.go
deleted file mode 100644
index 795db7c89..000000000
--- a/vendor/cloud.google.com/go/spanner/mutation_test.go
+++ /dev/null
@@ -1,543 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"reflect"
-	"sort"
-	"strings"
-	"testing"
-
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-)
-
-// keysetProto returns protobuf encoding of valid spanner.KeySet.
-func keysetProto(t *testing.T, ks KeySet) *sppb.KeySet {
-	k, err := ks.keySetProto()
-	if err != nil {
-		t.Fatalf("cannot convert keyset %v to protobuf: %v", ks, err)
-	}
-	return k
-}
-
-// Test encoding from spanner.Mutation to protobuf.
-func TestMutationToProto(t *testing.T) {
-	for i, test := range []struct {
-		m    *Mutation
-		want *sppb.Mutation
-	}{
-		// Delete Mutation
-		{
-			&Mutation{opDelete, "t_foo", Key{"foo"}, nil, nil},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_Delete_{
-					Delete: &sppb.Mutation_Delete{
-						Table:  "t_foo",
-						KeySet: keysetProto(t, Key{"foo"}),
-					},
-				},
-			},
-		},
-		// Insert Mutation
-		{
-			&Mutation{opInsert, "t_foo", KeySets(), []string{"col1", "col2"}, []interface{}{int64(1), int64(2)}},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_Insert{
-					Insert: &sppb.Mutation_Write{
-						Table:   "t_foo",
-						Columns: []string{"col1", "col2"},
-						Values: []*proto3.ListValue{
-							&proto3.ListValue{
-								Values: []*proto3.Value{intProto(1), intProto(2)},
-							},
-						},
-					},
-				},
-			},
-		},
-		// InsertOrUpdate Mutation
-		{
-			&Mutation{opInsertOrUpdate, "t_foo", KeySets(), []string{"col1", "col2"}, []interface{}{1.0, 2.0}},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_InsertOrUpdate{
-					InsertOrUpdate: &sppb.Mutation_Write{
-						Table:   "t_foo",
-						Columns: []string{"col1", "col2"},
-						Values: []*proto3.ListValue{
-							&proto3.ListValue{
-								Values: []*proto3.Value{floatProto(1.0), floatProto(2.0)},
-							},
-						},
-					},
-				},
-			},
-		},
-		// Replace Mutation
-		{
-			&Mutation{opReplace, "t_foo", KeySets(), []string{"col1", "col2"}, []interface{}{"one", 2.0}},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_Replace{
-					Replace: &sppb.Mutation_Write{
-						Table:   "t_foo",
-						Columns: []string{"col1", "col2"},
-						Values: []*proto3.ListValue{
-							&proto3.ListValue{
-								Values: []*proto3.Value{stringProto("one"), floatProto(2.0)},
-							},
-						},
-					},
-				},
-			},
-		},
-		// Update Mutation
-		{
-			&Mutation{opUpdate, "t_foo", KeySets(), []string{"col1", "col2"}, []interface{}{"one", []byte(nil)}},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_Update{
-					Update: &sppb.Mutation_Write{
-						Table:   "t_foo",
-						Columns: []string{"col1", "col2"},
-						Values: []*proto3.ListValue{
-							&proto3.ListValue{
-								Values: []*proto3.Value{stringProto("one"), nullProto()},
-							},
-						},
-					},
-				},
-			},
-		},
-	} {
-		if got, err := test.m.proto(); err != nil || !reflect.DeepEqual(got, test.want) {
-			t.Errorf("%d: (%#v).proto() = (%v, %v), want (%v, nil)", i, test.m, got, err, test.want)
-		}
-	}
-}
-
-// mutationColumnSorter implements sort.Interface for sorting column-value pairs in a Mutation by column names.
-type mutationColumnSorter struct {
-	Mutation
-}
-
-// newMutationColumnSorter creates new instance of mutationColumnSorter by duplicating the input Mutation so that
-// sorting won't change the input Mutation.
-func newMutationColumnSorter(m *Mutation) *mutationColumnSorter {
-	return &mutationColumnSorter{
-		Mutation{
-			m.op,
-			m.table,
-			m.keySet,
-			append([]string(nil), m.columns...),
-			append([]interface{}(nil), m.values...),
-		},
-	}
-}
-
-// Len implements sort.Interface.Len.
-func (ms *mutationColumnSorter) Len() int {
-	return len(ms.columns)
-}
-
-// Swap implements sort.Interface.Swap.
-func (ms *mutationColumnSorter) Swap(i, j int) {
-	ms.columns[i], ms.columns[j] = ms.columns[j], ms.columns[i]
-	ms.values[i], ms.values[j] = ms.values[j], ms.values[i]
-}
-
-// Less implements sort.Interface.Less.
-func (ms *mutationColumnSorter) Less(i, j int) bool {
-	return strings.Compare(ms.columns[i], ms.columns[j]) < 0
-}
-
-// mutationEqual returns true if two mutations in question are equal
-// to each other.
-func mutationEqual(t *testing.T, m1, m2 Mutation) bool {
-	// Two mutations are considered to be equal even if their column values have different
-	// orders.
-	ms1 := newMutationColumnSorter(&m1)
-	ms2 := newMutationColumnSorter(&m2)
-	sort.Sort(ms1)
-	sort.Sort(ms2)
-	return reflect.DeepEqual(ms1, ms2)
-}
-
-// Test helper functions which help to generate spanner.Mutation.
-func TestMutationHelpers(t *testing.T) {
-	for _, test := range []struct {
-		m    string
-		got  *Mutation
-		want *Mutation
-	}{
-		{
-			"Insert",
-			Insert("t_foo", []string{"col1", "col2"}, []interface{}{int64(1), int64(2)}),
-			&Mutation{opInsert, "t_foo", nil, []string{"col1", "col2"}, []interface{}{int64(1), int64(2)}},
-		},
-		{
-			"InsertMap",
-			InsertMap("t_foo", map[string]interface{}{"col1": int64(1), "col2": int64(2)}),
-			&Mutation{opInsert, "t_foo", nil, []string{"col1", "col2"}, []interface{}{int64(1), int64(2)}},
-		},
-		{
-			"InsertStruct",
-			func() *Mutation {
-				m, err := InsertStruct(
-					"t_foo",
-					struct {
-						notCol bool
-						Col1   int64 `spanner:"col1"`
-						Col2   int64 `spanner:"col2"`
-					}{false, int64(1), int64(2)},
-				)
-				if err != nil {
-					t.Errorf("cannot convert struct into mutation: %v", err)
-				}
-				return m
-			}(),
-			&Mutation{opInsert, "t_foo", nil, []string{"col1", "col2"}, []interface{}{int64(1), int64(2)}},
-		},
-		{
-			"Update",
-			Update("t_foo", []string{"col1", "col2"}, []interface{}{"one", []byte(nil)}),
-			&Mutation{opUpdate, "t_foo", nil, []string{"col1", "col2"}, []interface{}{"one", []byte(nil)}},
-		},
-		{
-			"UpdateMap",
-			UpdateMap("t_foo", map[string]interface{}{"col1": "one", "col2": []byte(nil)}),
-			&Mutation{opUpdate, "t_foo", nil, []string{"col1", "col2"}, []interface{}{"one", []byte(nil)}},
-		},
-		{
-			"UpdateStruct",
-			func() *Mutation {
-				m, err := UpdateStruct(
-					"t_foo",
-					struct {
-						Col1   string `spanner:"col1"`
-						notCol int
-						Col2   []byte `spanner:"col2"`
-					}{"one", 1, nil},
-				)
-				if err != nil {
-					t.Errorf("cannot convert struct into mutation: %v", err)
-				}
-				return m
-			}(),
-			&Mutation{opUpdate, "t_foo", nil, []string{"col1", "col2"}, []interface{}{"one", []byte(nil)}},
-		},
-		{
-			"InsertOrUpdate",
-			InsertOrUpdate("t_foo", []string{"col1", "col2"}, []interface{}{1.0, 2.0}),
-			&Mutation{opInsertOrUpdate, "t_foo", nil, []string{"col1", "col2"}, []interface{}{1.0, 2.0}},
-		},
-		{
-			"InsertOrUpdateMap",
-			InsertOrUpdateMap("t_foo", map[string]interface{}{"col1": 1.0, "col2": 2.0}),
-			&Mutation{opInsertOrUpdate, "t_foo", nil, []string{"col1", "col2"}, []interface{}{1.0, 2.0}},
-		},
-		{
-			"InsertOrUpdateStruct",
-			func() *Mutation {
-				m, err := InsertOrUpdateStruct(
-					"t_foo",
-					struct {
-						Col1   float64 `spanner:"col1"`
-						Col2   float64 `spanner:"col2"`
-						notCol float64
-					}{1.0, 2.0, 3.0},
-				)
-				if err != nil {
-					t.Errorf("cannot convert struct into mutation: %v", err)
-				}
-				return m
-			}(),
-			&Mutation{opInsertOrUpdate, "t_foo", nil, []string{"col1", "col2"}, []interface{}{1.0, 2.0}},
-		},
-		{
-			"Replace",
-			Replace("t_foo", []string{"col1", "col2"}, []interface{}{"one", 2.0}),
-			&Mutation{opReplace, "t_foo", nil, []string{"col1", "col2"}, []interface{}{"one", 2.0}},
-		},
-		{
-			"ReplaceMap",
-			ReplaceMap("t_foo", map[string]interface{}{"col1": "one", "col2": 2.0}),
-			&Mutation{opReplace, "t_foo", nil, []string{"col1", "col2"}, []interface{}{"one", 2.0}},
-		},
-		{
-			"ReplaceStruct",
-			func() *Mutation {
-				m, err := ReplaceStruct(
-					"t_foo",
-					struct {
-						Col1   string  `spanner:"col1"`
-						Col2   float64 `spanner:"col2"`
-						notCol string
-					}{"one", 2.0, "foo"},
-				)
-				if err != nil {
-					t.Errorf("cannot convert struct into mutation: %v", err)
-				}
-				return m
-			}(),
-			&Mutation{opReplace, "t_foo", nil, []string{"col1", "col2"}, []interface{}{"one", 2.0}},
-		},
-		{
-			"Delete",
-			Delete("t_foo", Key{"foo"}),
-			&Mutation{opDelete, "t_foo", Key{"foo"}, nil, nil},
-		},
-		{
-			"DeleteRange",
-			Delete("t_foo", KeyRange{Key{"bar"}, Key{"foo"}, ClosedClosed}),
-			&Mutation{opDelete, "t_foo", KeyRange{Key{"bar"}, Key{"foo"}, ClosedClosed}, nil, nil},
-		},
-	} {
-		if !mutationEqual(t, *test.got, *test.want) {
-			t.Errorf("%v: got Mutation %v, want %v", test.m, test.got, test.want)
-		}
-	}
-}
-
-// Test encoding non-struct types by using *Struct helpers.
-func TestBadStructs(t *testing.T) {
-	val := "i_am_not_a_struct"
-	wantErr := errNotStruct(val)
-	if _, gotErr := InsertStruct("t_test", val); !reflect.DeepEqual(gotErr, wantErr) {
-		t.Errorf("InsertStruct(%q) returns error %v, want %v", val, gotErr, wantErr)
-	}
-	if _, gotErr := InsertOrUpdateStruct("t_test", val); !reflect.DeepEqual(gotErr, wantErr) {
-		t.Errorf("InsertOrUpdateStruct(%q) returns error %v, want %v", val, gotErr, wantErr)
-	}
-	if _, gotErr := UpdateStruct("t_test", val); !reflect.DeepEqual(gotErr, wantErr) {
-		t.Errorf("UpdateStruct(%q) returns error %v, want %v", val, gotErr, wantErr)
-	}
-	if _, gotErr := ReplaceStruct("t_test", val); !reflect.DeepEqual(gotErr, wantErr) {
-		t.Errorf("ReplaceStruct(%q) returns error %v, want %v", val, gotErr, wantErr)
-	}
-}
-
-// Test encoding Mutation into proto.
-func TestEncodeMutation(t *testing.T) {
-	for _, test := range []struct {
-		name      string
-		mutation  Mutation
-		wantProto *sppb.Mutation
-		wantErr   error
-	}{
-		{
-			"OpDelete",
-			Mutation{opDelete, "t_test", Key{1}, nil, nil},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_Delete_{
-					Delete: &sppb.Mutation_Delete{
-						Table: "t_test",
-						KeySet: &sppb.KeySet{
-							Keys: []*proto3.ListValue{listValueProto(intProto(1))},
-						},
-					},
-				},
-			},
-			nil,
-		},
-		{
-			"OpDelete - Key error",
-			Mutation{opDelete, "t_test", Key{struct{}{}}, nil, nil},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_Delete_{
-					Delete: &sppb.Mutation_Delete{
-						Table:  "t_test",
-						KeySet: &sppb.KeySet{},
-					},
-				},
-			},
-			errInvdKeyPartType(struct{}{}),
-		},
-		{
-			"OpInsert",
-			Mutation{opInsert, "t_test", nil, []string{"key", "val"}, []interface{}{"foo", 1}},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_Insert{
-					Insert: &sppb.Mutation_Write{
-						Table:   "t_test",
-						Columns: []string{"key", "val"},
-						Values:  []*proto3.ListValue{listValueProto(stringProto("foo"), intProto(1))},
-					},
-				},
-			},
-			nil,
-		},
-		{
-			"OpInsert - Value Type Error",
-			Mutation{opInsert, "t_test", nil, []string{"key", "val"}, []interface{}{struct{}{}, 1}},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_Insert{
-					Insert: &sppb.Mutation_Write{},
-				},
-			},
-			errEncoderUnsupportedType(struct{}{}),
-		},
-		{
-			"OpInsertOrUpdate",
-			Mutation{opInsertOrUpdate, "t_test", nil, []string{"key", "val"}, []interface{}{"foo", 1}},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_InsertOrUpdate{
-					InsertOrUpdate: &sppb.Mutation_Write{
-						Table:   "t_test",
-						Columns: []string{"key", "val"},
-						Values:  []*proto3.ListValue{listValueProto(stringProto("foo"), intProto(1))},
-					},
-				},
-			},
-			nil,
-		},
-		{
-			"OpInsertOrUpdate - Value Type Error",
-			Mutation{opInsertOrUpdate, "t_test", nil, []string{"key", "val"}, []interface{}{struct{}{}, 1}},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_InsertOrUpdate{
-					InsertOrUpdate: &sppb.Mutation_Write{},
-				},
-			},
-			errEncoderUnsupportedType(struct{}{}),
-		},
-		{
-			"OpReplace",
-			Mutation{opReplace, "t_test", nil, []string{"key", "val"}, []interface{}{"foo", 1}},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_Replace{
-					Replace: &sppb.Mutation_Write{
-						Table:   "t_test",
-						Columns: []string{"key", "val"},
-						Values:  []*proto3.ListValue{listValueProto(stringProto("foo"), intProto(1))},
-					},
-				},
-			},
-			nil,
-		},
-		{
-			"OpReplace - Value Type Error",
-			Mutation{opReplace, "t_test", nil, []string{"key", "val"}, []interface{}{struct{}{}, 1}},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_Replace{
-					Replace: &sppb.Mutation_Write{},
-				},
-			},
-			errEncoderUnsupportedType(struct{}{}),
-		},
-		{
-			"OpUpdate",
-			Mutation{opUpdate, "t_test", nil, []string{"key", "val"}, []interface{}{"foo", 1}},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_Update{
-					Update: &sppb.Mutation_Write{
-						Table:   "t_test",
-						Columns: []string{"key", "val"},
-						Values:  []*proto3.ListValue{listValueProto(stringProto("foo"), intProto(1))},
-					},
-				},
-			},
-			nil,
-		},
-		{
-			"OpUpdate - Value Type Error",
-			Mutation{opUpdate, "t_test", nil, []string{"key", "val"}, []interface{}{struct{}{}, 1}},
-			&sppb.Mutation{
-				Operation: &sppb.Mutation_Update{
-					Update: &sppb.Mutation_Write{},
-				},
-			},
-			errEncoderUnsupportedType(struct{}{}),
-		},
-		{
-			"OpKnown - Unknown Mutation Operation Code",
-			Mutation{op(100), "t_test", nil, nil, nil},
-			&sppb.Mutation{},
-			errInvdMutationOp(Mutation{op(100), "t_test", nil, nil, nil}),
-		},
-	} {
-		gotProto, gotErr := test.mutation.proto()
-		if gotErr != nil {
-			if !reflect.DeepEqual(gotErr, test.wantErr) {
-				t.Errorf("%s: %v.proto() returns error %v, want %v", test.name, test.mutation, gotErr, test.wantErr)
-			}
-			continue
-		}
-		if !reflect.DeepEqual(gotProto, test.wantProto) {
-			t.Errorf("%s: %v.proto() = (%v, nil), want (%v, nil)", test.name, test.mutation, gotProto, test.wantProto)
-		}
-	}
-}
-
-// Test Encoding an array of mutations.
-func TestEncodeMutationArray(t *testing.T) {
-	for _, test := range []struct {
-		name    string
-		ms      []*Mutation
-		want    []*sppb.Mutation
-		wantErr error
-	}{
-		{
-			"Multiple Mutations",
-			[]*Mutation{
-				&Mutation{opDelete, "t_test", Key{"bar"}, nil, nil},
-				&Mutation{opInsertOrUpdate, "t_test", nil, []string{"key", "val"}, []interface{}{"foo", 1}},
-			},
-			[]*sppb.Mutation{
-				&sppb.Mutation{
-					Operation: &sppb.Mutation_Delete_{
-						Delete: &sppb.Mutation_Delete{
-							Table: "t_test",
-							KeySet: &sppb.KeySet{
-								Keys: []*proto3.ListValue{listValueProto(stringProto("bar"))},
-							},
-						},
-					},
-				},
-				&sppb.Mutation{
-					Operation: &sppb.Mutation_InsertOrUpdate{
-						InsertOrUpdate: &sppb.Mutation_Write{
-							Table:   "t_test",
-							Columns: []string{"key", "val"},
-							Values:  []*proto3.ListValue{listValueProto(stringProto("foo"), intProto(1))},
-						},
-					},
-				},
-			},
-			nil,
-		},
-		{
-			"Multiple Mutations - Bad Mutation",
-			[]*Mutation{
-				&Mutation{opDelete, "t_test", Key{"bar"}, nil, nil},
-				&Mutation{opInsertOrUpdate, "t_test", nil, []string{"key", "val"}, []interface{}{"foo", struct{}{}}},
-			},
-			[]*sppb.Mutation{},
-			errEncoderUnsupportedType(struct{}{}),
-		},
-	} {
-		gotProto, gotErr := mutationsProto(test.ms)
-		if gotErr != nil {
-			if !reflect.DeepEqual(gotErr, test.wantErr) {
-				t.Errorf("%v: mutationsProto(%v) returns error %v, want %v", test.name, test.ms, gotErr, test.wantErr)
-			}
-			continue
-		}
-		if !reflect.DeepEqual(gotProto, test.want) {
-			t.Errorf("%v: mutationsProto(%v) = (%v, nil), want (%v, nil)", test.name, test.ms, gotProto, test.want)
-		}
-	}
-}
diff --git a/vendor/cloud.google.com/go/spanner/protoutils.go b/vendor/cloud.google.com/go/spanner/protoutils.go
deleted file mode 100644
index df12432d5..000000000
--- a/vendor/cloud.google.com/go/spanner/protoutils.go
+++ /dev/null
@@ -1,113 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"encoding/base64"
-	"strconv"
-	"time"
-
-	"cloud.google.com/go/civil"
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-)
-
-// Helpers to generate protobuf values and Cloud Spanner types.
-
-func stringProto(s string) *proto3.Value {
-	return &proto3.Value{Kind: stringKind(s)}
-}
-
-func stringKind(s string) *proto3.Value_StringValue {
-	return &proto3.Value_StringValue{StringValue: s}
-}
-
-func stringType() *sppb.Type {
-	return &sppb.Type{Code: sppb.TypeCode_STRING}
-}
-
-func boolProto(b bool) *proto3.Value {
-	return &proto3.Value{Kind: &proto3.Value_BoolValue{BoolValue: b}}
-}
-
-func boolType() *sppb.Type {
-	return &sppb.Type{Code: sppb.TypeCode_BOOL}
-}
-
-func intProto(n int64) *proto3.Value {
-	return &proto3.Value{Kind: &proto3.Value_StringValue{StringValue: strconv.FormatInt(n, 10)}}
-}
-
-func intType() *sppb.Type {
-	return &sppb.Type{Code: sppb.TypeCode_INT64}
-}
-
-func floatProto(n float64) *proto3.Value {
-	return &proto3.Value{Kind: &proto3.Value_NumberValue{NumberValue: n}}
-}
-
-func floatType() *sppb.Type {
-	return &sppb.Type{Code: sppb.TypeCode_FLOAT64}
-}
-
-func bytesProto(b []byte) *proto3.Value {
-	return &proto3.Value{Kind: &proto3.Value_StringValue{StringValue: base64.StdEncoding.EncodeToString(b)}}
-}
-
-func bytesType() *sppb.Type {
-	return &sppb.Type{Code: sppb.TypeCode_BYTES}
-}
-
-func timeProto(t time.Time) *proto3.Value {
-	return stringProto(t.UTC().Format(time.RFC3339Nano))
-}
-
-func timeType() *sppb.Type {
-	return &sppb.Type{Code: sppb.TypeCode_TIMESTAMP}
-}
-
-func dateProto(d civil.Date) *proto3.Value {
-	return stringProto(d.String())
-}
-
-func dateType() *sppb.Type {
-	return &sppb.Type{Code: sppb.TypeCode_DATE}
-}
-
-func listProto(p ...*proto3.Value) *proto3.Value {
-	return &proto3.Value{Kind: &proto3.Value_ListValue{ListValue: &proto3.ListValue{Values: p}}}
-}
-
-func listValueProto(p ...*proto3.Value) *proto3.ListValue {
-	return &proto3.ListValue{Values: p}
-}
-
-func listType(t *sppb.Type) *sppb.Type {
-	return &sppb.Type{Code: sppb.TypeCode_ARRAY, ArrayElementType: t}
-}
-
-func mkField(n string, t *sppb.Type) *sppb.StructType_Field {
-	return &sppb.StructType_Field{n, t}
-}
-
-func structType(fields ...*sppb.StructType_Field) *sppb.Type {
-	return &sppb.Type{Code: sppb.TypeCode_STRUCT, StructType: &sppb.StructType{Fields: fields}}
-}
-
-func nullProto() *proto3.Value {
-	return &proto3.Value{Kind: &proto3.Value_NullValue{NullValue: proto3.NullValue_NULL_VALUE}}
-}
diff --git a/vendor/cloud.google.com/go/spanner/read.go b/vendor/cloud.google.com/go/spanner/read.go
deleted file mode 100644
index 5d733f1ca..000000000
--- a/vendor/cloud.google.com/go/spanner/read.go
+++ /dev/null
@@ -1,685 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"bytes"
-	"io"
-	"sync/atomic"
-	"time"
-
-	log "github.com/golang/glog"
-	proto "github.com/golang/protobuf/proto"
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-	"golang.org/x/net/context"
-
-	"google.golang.org/api/iterator"
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-	"google.golang.org/grpc/codes"
-)
-
-// streamingReceiver is the interface for receiving data from a client side
-// stream.
-type streamingReceiver interface {
-	Recv() (*sppb.PartialResultSet, error)
-}
-
-// errEarlyReadEnd returns error for read finishes when gRPC stream is still active.
-func errEarlyReadEnd() error {
-	return spannerErrorf(codes.FailedPrecondition, "read completed with active stream")
-}
-
-// stream is the internal fault tolerant method for streaming data from
-// Cloud Spanner.
-func stream(ctx context.Context, rpc func(ct context.Context, resumeToken []byte) (streamingReceiver, error), setTimestamp func(time.Time), release func(error)) *RowIterator {
-	ctx, cancel := context.WithCancel(ctx)
-	return &RowIterator{
-		streamd:      newResumableStreamDecoder(ctx, rpc),
-		rowd:         &partialResultSetDecoder{},
-		setTimestamp: setTimestamp,
-		release:      release,
-		cancel:       cancel,
-	}
-}
-
-// RowIterator is an iterator over Rows.
-type RowIterator struct {
-	streamd      *resumableStreamDecoder
-	rowd         *partialResultSetDecoder
-	setTimestamp func(time.Time)
-	release      func(error)
-	cancel       func()
-	err          error
-	rows         []*Row
-}
-
-// Next returns the next result. Its second return value is iterator.Done if
-// there are no more results. Once Next returns Done, all subsequent calls
-// will return Done.
-func (r *RowIterator) Next() (*Row, error) {
-	if r.err != nil {
-		return nil, r.err
-	}
-	for len(r.rows) == 0 && r.streamd.next() {
-		r.rows, r.err = r.rowd.add(r.streamd.get())
-		if r.err != nil {
-			return nil, r.err
-		}
-		if !r.rowd.ts.IsZero() && r.setTimestamp != nil {
-			r.setTimestamp(r.rowd.ts)
-			r.setTimestamp = nil
-		}
-	}
-	if len(r.rows) > 0 {
-		row := r.rows[0]
-		r.rows = r.rows[1:]
-		return row, nil
-	}
-	if err := r.streamd.lastErr(); err != nil {
-		r.err = toSpannerError(err)
-	} else if !r.rowd.done() {
-		r.err = errEarlyReadEnd()
-	} else {
-		r.err = iterator.Done
-	}
-	return nil, r.err
-}
-
-// Do calls the provided function once in sequence for each row in the iteration.  If the
-// function returns a non-nil error, Do immediately returns that error.
-//
-// If there are no rows in the iterator, Do will return nil without calling the
-// provided function.
-//
-// Do always calls Stop on the iterator.
-func (r *RowIterator) Do(f func(r *Row) error) error {
-	defer r.Stop()
-	for {
-		row, err := r.Next()
-		switch err {
-		case iterator.Done:
-			return nil
-		case nil:
-			if err = f(row); err != nil {
-				return err
-			}
-		default:
-			return err
-		}
-	}
-}
-
-// Stop terminates the iteration. It should be called after every iteration.
-func (r *RowIterator) Stop() {
-	if r.cancel != nil {
-		r.cancel()
-	}
-	if r.release != nil {
-		r.release(r.err)
-		if r.err == nil {
-			r.err = spannerErrorf(codes.FailedPrecondition, "Next called after Stop")
-		}
-		r.release = nil
-
-	}
-}
-
-// partialResultQueue implements a simple FIFO queue.  The zero value is a
-// valid queue.
-type partialResultQueue struct {
-	q     []*sppb.PartialResultSet
-	first int
-	last  int
-	n     int // number of elements in queue
-}
-
-// empty returns if the partialResultQueue is empty.
-func (q *partialResultQueue) empty() bool {
-	return q.n == 0
-}
-
-// errEmptyQueue returns error for dequeuing an empty queue.
-func errEmptyQueue() error {
-	return spannerErrorf(codes.OutOfRange, "empty partialResultQueue")
-}
-
-// peekLast returns the last item in partialResultQueue; if the queue
-// is empty, it returns error.
-func (q *partialResultQueue) peekLast() (*sppb.PartialResultSet, error) {
-	if q.empty() {
-		return nil, errEmptyQueue()
-	}
-	return q.q[(q.last+cap(q.q)-1)%cap(q.q)], nil
-}
-
-// push adds an item to the tail of partialResultQueue.
-func (q *partialResultQueue) push(r *sppb.PartialResultSet) {
-	if q.q == nil {
-		q.q = make([]*sppb.PartialResultSet, 8 /* arbitrary */)
-	}
-	if q.n == cap(q.q) {
-		buf := make([]*sppb.PartialResultSet, cap(q.q)*2)
-		for i := 0; i < q.n; i++ {
-			buf[i] = q.q[(q.first+i)%cap(q.q)]
-		}
-		q.q = buf
-		q.first = 0
-		q.last = q.n
-	}
-	q.q[q.last] = r
-	q.last = (q.last + 1) % cap(q.q)
-	q.n++
-}
-
-// pop removes an item from the head of partialResultQueue and returns
-// it.
-func (q *partialResultQueue) pop() *sppb.PartialResultSet {
-	if q.n == 0 {
-		return nil
-	}
-	r := q.q[q.first]
-	q.q[q.first] = nil
-	q.first = (q.first + 1) % cap(q.q)
-	q.n--
-	return r
-}
-
-// clear empties partialResultQueue.
-func (q *partialResultQueue) clear() {
-	*q = partialResultQueue{}
-}
-
-// dump retrieves all items from partialResultQueue and return them in a slice.
-// It is used only in tests.
-func (q *partialResultQueue) dump() []*sppb.PartialResultSet {
-	var dq []*sppb.PartialResultSet
-	for i := q.first; len(dq) < q.n; i = (i + 1) % cap(q.q) {
-		dq = append(dq, q.q[i])
-	}
-	return dq
-}
-
-// resumableStreamDecoderState encodes resumableStreamDecoder's status.
-// See also the comments for resumableStreamDecoder.Next.
-type resumableStreamDecoderState int
-
-const (
-	unConnected         resumableStreamDecoderState = iota // 0
-	queueingRetryable                                      // 1
-	queueingUnretryable                                    // 2
-	aborted                                                // 3
-	finished                                               // 4
-)
-
-// resumableStreamDecoder provides a resumable interface for receiving
-// sppb.PartialResultSet(s) from a given query wrapped by
-// resumableStreamDecoder.rpc().
-type resumableStreamDecoder struct {
-	// state is the current status of resumableStreamDecoder, see also
-	// the comments for resumableStreamDecoder.Next.
-	state resumableStreamDecoderState
-	// stateWitness when non-nil is called to observe state change,
-	// used for testing.
-	stateWitness func(resumableStreamDecoderState)
-	// ctx is the caller's context, used for cancel/timeout Next().
-	ctx context.Context
-	// rpc is a factory of streamingReceiver, which might resume
-	// a pervious stream from the point encoded in restartToken.
-	// rpc is always a wrapper of a Cloud Spanner query which is
-	// resumable.
-	rpc func(ctx context.Context, restartToken []byte) (streamingReceiver, error)
-	// stream is the current RPC streaming receiver.
-	stream streamingReceiver
-	// q buffers received yet undecoded partial results.
-	q partialResultQueue
-	// bytesBetweenResumeTokens is the proxy of the byte size of PartialResultSets being queued
-	// between two resume tokens. Once bytesBetweenResumeTokens is greater than
-	// maxBytesBetweenResumeTokens, resumableStreamDecoder goes into queueingUnretryable state.
-	bytesBetweenResumeTokens int32
-	// maxBytesBetweenResumeTokens is the max number of bytes that can be buffered
-	// between two resume tokens. It is always copied from the global maxBytesBetweenResumeTokens
-	// atomically.
-	maxBytesBetweenResumeTokens int32
-	// np is the next sppb.PartialResultSet ready to be returned
-	// to caller of resumableStreamDecoder.Get().
-	np *sppb.PartialResultSet
-	// resumeToken stores the resume token that resumableStreamDecoder has
-	// last revealed to caller.
-	resumeToken []byte
-	// retryCount is the number of retries that have been carried out so far
-	retryCount int
-	// err is the last error resumableStreamDecoder has encountered so far.
-	err error
-	// backoff to compute delays between retries.
-	backoff exponentialBackoff
-}
-
-// newResumableStreamDecoder creates a new resumeableStreamDecoder instance.
-// Parameter rpc should be a function that creates a new stream
-// beginning at the restartToken if non-nil.
-func newResumableStreamDecoder(ctx context.Context, rpc func(ct context.Context, restartToken []byte) (streamingReceiver, error)) *resumableStreamDecoder {
-	return &resumableStreamDecoder{
-		ctx: ctx,
-		rpc: rpc,
-		maxBytesBetweenResumeTokens: atomic.LoadInt32(&maxBytesBetweenResumeTokens),
-		backoff:                     defaultBackoff,
-	}
-}
-
-// changeState fulfills state transition for resumableStateDecoder.
-func (d *resumableStreamDecoder) changeState(target resumableStreamDecoderState) {
-	if d.state == queueingRetryable && d.state != target {
-		// Reset bytesBetweenResumeTokens because it is only meaningful/changed under
-		// queueingRetryable state.
-		d.bytesBetweenResumeTokens = 0
-	}
-	d.state = target
-	if d.stateWitness != nil {
-		d.stateWitness(target)
-	}
-}
-
-// isNewResumeToken returns if the observed resume token is different from
-// the one returned from server last time.
-func (d *resumableStreamDecoder) isNewResumeToken(rt []byte) bool {
-	if rt == nil {
-		return false
-	}
-	if bytes.Compare(rt, d.resumeToken) == 0 {
-		return false
-	}
-	return true
-}
-
-// Next advances to the next available partial result set.  If error or no
-// more, returns false, call Err to determine if an error was encountered.
-// The following diagram illustrates the state machine of resumableStreamDecoder
-// that Next() implements. Note that state transition can be only triggered by
-// RPC activities.
-/*
-        rpc() fails retryable
-      +---------+
-      |         |    rpc() fails unretryable/ctx timeouts or cancelled
-      |         |   +------------------------------------------------+
-      |         |   |                                                |
-      |         v   |                                                v
-      |     +---+---+---+                       +--------+    +------+--+
-      +-----+unConnected|                       |finished|    | aborted |<----+
-            |           |                       ++-----+-+    +------+--+     |
-            +---+----+--+                        ^     ^             ^        |
-                |    ^                           |     |             |        |
-                |    |                           |     |     recv() fails     |
-                |    |                           |     |             |        |
-                |    |recv() fails retryable     |     |             |        |
-                |    |with valid ctx             |     |             |        |
-                |    |                           |     |             |        |
-      rpc() succeeds |   +-----------------------+     |             |        |
-                |    |   |         recv EOF         recv EOF         |        |
-                |    |   |                             |             |        |
-                v    |   |     Queue size exceeds      |             |        |
-            +---+----+---+----+threshold       +-------+-----------+ |        |
-+---------->+                 +--------------->+                   +-+        |
-|           |queueingRetryable|                |queueingUnretryable|          |
-|           |                 +<---------------+                   |          |
-|           +---+----------+--+ pop() returns  +--+----+-----------+          |
-|               |          |    resume token      |    ^                      |
-|               |          |                      |    |                      |
-|               |          |                      |    |                      |
-+---------------+          |                      |    |                      |
-   recv() succeeds         |                      +----+                      |
-                           |                      recv() succeeds             |
-                           |                                                  |
-                           |                                                  |
-                           |                                                  |
-                           |                                                  |
-                           |                                                  |
-                           +--------------------------------------------------+
-                                               recv() fails unretryable
-
-*/
-var (
-	// maxBytesBetweenResumeTokens is the maximum amount of bytes that resumableStreamDecoder
-	// in queueingRetryable state can use to queue PartialResultSets before getting
-	// into queueingUnretryable state.
-	maxBytesBetweenResumeTokens = int32(128 * 1024 * 1024)
-)
-
-func (d *resumableStreamDecoder) next() bool {
-	for {
-		select {
-		case <-d.ctx.Done():
-			// Do context check here so that even gRPC failed to do
-			// so, resumableStreamDecoder can still break the loop
-			// as expected.
-			d.err = errContextCanceled(d.ctx, d.err)
-			d.changeState(aborted)
-		default:
-		}
-		switch d.state {
-		case unConnected:
-			// If no gRPC stream is available, try to initiate one.
-			if d.stream, d.err = d.rpc(d.ctx, d.resumeToken); d.err != nil {
-				if isRetryable(d.err) {
-					d.doBackOff()
-					// Be explicit about state transition, although the
-					// state doesn't actually change. State transition
-					// will be triggered only by RPC activity, regardless of
-					// whether there is an actual state change or not.
-					d.changeState(unConnected)
-					continue
-				}
-				d.changeState(aborted)
-				continue
-			}
-			d.resetBackOff()
-			d.changeState(queueingRetryable)
-			continue
-		case queueingRetryable:
-			fallthrough
-		case queueingUnretryable:
-			// Receiving queue is not empty.
-			last, err := d.q.peekLast()
-			if err != nil {
-				// Only the case that receiving queue is empty could cause peekLast to
-				// return error and in such case, we should try to receive from stream.
-				d.tryRecv()
-				continue
-			}
-			if d.isNewResumeToken(last.ResumeToken) {
-				// Got new resume token, return buffered sppb.PartialResultSets to caller.
-				d.np = d.q.pop()
-				if d.q.empty() {
-					d.bytesBetweenResumeTokens = 0
-					// The new resume token was just popped out from queue, record it.
-					d.resumeToken = d.np.ResumeToken
-					d.changeState(queueingRetryable)
-				}
-				return true
-			}
-			if d.bytesBetweenResumeTokens >= d.maxBytesBetweenResumeTokens && d.state == queueingRetryable {
-				d.changeState(queueingUnretryable)
-				continue
-			}
-			if d.state == queueingUnretryable {
-				// When there is no resume token observed,
-				// only yield sppb.PartialResultSets to caller under
-				// queueingUnretryable state.
-				d.np = d.q.pop()
-				return true
-			}
-			// Needs to receive more from gRPC stream till a new resume token
-			// is observed.
-			d.tryRecv()
-			continue
-		case aborted:
-			// Discard all pending items because none of them
-			// should be yield to caller.
-			d.q.clear()
-			return false
-		case finished:
-			// If query has finished, check if there are still buffered messages.
-			if d.q.empty() {
-				// No buffered PartialResultSet.
-				return false
-			}
-			// Although query has finished, there are still buffered PartialResultSets.
-			d.np = d.q.pop()
-			return true
-
-		default:
-			log.Errorf("Unexpected resumableStreamDecoder.state: %v", d.state)
-			return false
-		}
-	}
-}
-
-// tryRecv attempts to receive a PartialResultSet from gRPC stream.
-func (d *resumableStreamDecoder) tryRecv() {
-	var res *sppb.PartialResultSet
-	if res, d.err = d.stream.Recv(); d.err != nil {
-		if d.err == io.EOF {
-			d.err = nil
-			d.changeState(finished)
-			return
-		}
-		if isRetryable(d.err) && d.state == queueingRetryable {
-			d.err = nil
-			// Discard all queue items (none have resume tokens).
-			d.q.clear()
-			d.stream = nil
-			d.changeState(unConnected)
-			d.doBackOff()
-			return
-		}
-		d.changeState(aborted)
-		return
-	}
-	d.q.push(res)
-	if d.state == queueingRetryable && !d.isNewResumeToken(res.ResumeToken) {
-		// adjusting d.bytesBetweenResumeTokens
-		d.bytesBetweenResumeTokens += int32(proto.Size(res))
-	}
-	d.resetBackOff()
-	d.changeState(d.state)
-}
-
-// resetBackOff clears the internal retry counter of
-// resumableStreamDecoder so that the next exponential
-// backoff will start at a fresh state.
-func (d *resumableStreamDecoder) resetBackOff() {
-	d.retryCount = 0
-}
-
-// doBackoff does an exponential backoff sleep.
-func (d *resumableStreamDecoder) doBackOff() {
-	ticker := time.NewTicker(d.backoff.delay(d.retryCount))
-	defer ticker.Stop()
-	d.retryCount++
-	select {
-	case <-d.ctx.Done():
-	case <-ticker.C:
-	}
-}
-
-// get returns the most recent PartialResultSet generated by a call to next.
-func (d *resumableStreamDecoder) get() *sppb.PartialResultSet {
-	return d.np
-}
-
-// lastErr returns the last non-EOF error encountered.
-func (d *resumableStreamDecoder) lastErr() error {
-	return d.err
-}
-
-// partialResultSetDecoder assembles PartialResultSet(s) into Cloud Spanner
-// Rows.
-type partialResultSetDecoder struct {
-	row     Row
-	tx      *sppb.Transaction
-	chunked bool      // if true, next value should be merged with last values entry.
-	ts      time.Time // read timestamp
-}
-
-// yield checks we have a complete row, and if so returns it.  A row is not
-// complete if it doesn't have enough columns, or if this is a chunked response
-// and there are no further values to process.
-func (p *partialResultSetDecoder) yield(chunked, last bool) *Row {
-	if len(p.row.vals) == len(p.row.fields) && (!chunked || !last) {
-		// When partialResultSetDecoder gets enough number of
-		// Column values, There are two cases that a new Row
-		// should be yield:
-		//   1. The incoming PartialResultSet is not chunked;
-		//   2. The incoming PartialResultSet is chunked, but the
-		//      proto3.Value being merged is not the last one in
-		//      the PartialResultSet.
-		//
-		// Use a fresh Row to simplify clients that want to use yielded results
-		// after the next row is retrieved. Note that fields is never changed
-		// so it doesn't need to be copied.
-		fresh := Row{
-			fields: p.row.fields,
-			vals:   make([]*proto3.Value, len(p.row.vals)),
-		}
-		copy(fresh.vals, p.row.vals)
-		p.row.vals = p.row.vals[:0] // empty and reuse slice
-		return &fresh
-	}
-	return nil
-}
-
-// yieldTx returns transaction information via caller supplied callback.
-func errChunkedEmptyRow() error {
-	return spannerErrorf(codes.FailedPrecondition, "got invalid chunked PartialResultSet with empty Row")
-}
-
-// add tries to merge a new PartialResultSet into buffered Row. It returns
-// any rows that have been completed as a result.
-func (p *partialResultSetDecoder) add(r *sppb.PartialResultSet) ([]*Row, error) {
-	var rows []*Row
-	if r.Metadata != nil {
-		// Metadata should only be returned in the first result.
-		if p.row.fields == nil {
-			p.row.fields = r.Metadata.RowType.Fields
-		}
-		if p.tx == nil && r.Metadata.Transaction != nil {
-			p.tx = r.Metadata.Transaction
-			if p.tx.ReadTimestamp != nil {
-				p.ts = time.Unix(p.tx.ReadTimestamp.Seconds, int64(p.tx.ReadTimestamp.Nanos))
-			}
-		}
-	}
-	if len(r.Values) == 0 {
-		return nil, nil
-	}
-	if p.chunked {
-		p.chunked = false
-		// Try to merge first value in r.Values into
-		// uncompleted row.
-		last := len(p.row.vals) - 1
-		if last < 0 { // sanity check
-			return nil, errChunkedEmptyRow()
-		}
-		var err error
-		// If p is chunked, then we should always try to merge p.last with r.first.
-		if p.row.vals[last], err = p.merge(p.row.vals[last], r.Values[0]); err != nil {
-			return nil, err
-		}
-		r.Values = r.Values[1:]
-		// Merge is done, try to yield a complete Row.
-		if row := p.yield(r.ChunkedValue, len(r.Values) == 0); row != nil {
-			rows = append(rows, row)
-		}
-	}
-	for i, v := range r.Values {
-		// The rest values in r can be appened into p directly.
-		p.row.vals = append(p.row.vals, v)
-		// Again, check to see if a complete Row can be yielded because of
-		// the newly added value.
-		if row := p.yield(r.ChunkedValue, i == len(r.Values)-1); row != nil {
-			rows = append(rows, row)
-		}
-	}
-	if r.ChunkedValue {
-		// After dealing with all values in r, if r is chunked then p must
-		// be also chunked.
-		p.chunked = true
-	}
-	return rows, nil
-}
-
-// isMergeable returns if a protobuf Value can be potentially merged with
-// other protobuf Values.
-func (p *partialResultSetDecoder) isMergeable(a *proto3.Value) bool {
-	switch a.Kind.(type) {
-	case *proto3.Value_StringValue:
-		return true
-	case *proto3.Value_ListValue:
-		return true
-	default:
-		return false
-	}
-}
-
-// errIncompatibleMergeTypes returns error for incompatible protobuf types
-// that cannot be merged by partialResultSetDecoder.
-func errIncompatibleMergeTypes(a, b *proto3.Value) error {
-	return spannerErrorf(codes.FailedPrecondition, "incompatible type in chunked PartialResultSet. expected (%T), got (%T)", a.Kind, b.Kind)
-}
-
-// errUnsupportedMergeType returns error for protobuf type that cannot be
-// merged to other protobufs.
-func errUnsupportedMergeType(a *proto3.Value) error {
-	return spannerErrorf(codes.FailedPrecondition, "unsupported type merge (%T)", a.Kind)
-}
-
-// merge tries to combine two protobuf Values if possible.
-func (p *partialResultSetDecoder) merge(a, b *proto3.Value) (*proto3.Value, error) {
-	var err error
-	typeErr := errIncompatibleMergeTypes(a, b)
-	switch t := a.Kind.(type) {
-	case *proto3.Value_StringValue:
-		s, ok := b.Kind.(*proto3.Value_StringValue)
-		if !ok {
-			return nil, typeErr
-		}
-		return &proto3.Value{
-			Kind: &proto3.Value_StringValue{StringValue: t.StringValue + s.StringValue},
-		}, nil
-	case *proto3.Value_ListValue:
-		l, ok := b.Kind.(*proto3.Value_ListValue)
-		if !ok {
-			return nil, typeErr
-		}
-		if l.ListValue == nil || len(l.ListValue.Values) <= 0 {
-			// b is an empty list, just return a.
-			return a, nil
-		}
-		if t.ListValue == nil || len(t.ListValue.Values) <= 0 {
-			// a is an empty list, just return b.
-			return b, nil
-		}
-		if la := len(t.ListValue.Values) - 1; p.isMergeable(t.ListValue.Values[la]) {
-			// When the last item in a is of type String,
-			// List or Struct(encoded into List by Cloud Spanner),
-			// try to Merge last item in a and first item in b.
-			t.ListValue.Values[la], err = p.merge(t.ListValue.Values[la], l.ListValue.Values[0])
-			if err != nil {
-				return nil, err
-			}
-			l.ListValue.Values = l.ListValue.Values[1:]
-		}
-		return &proto3.Value{
-			Kind: &proto3.Value_ListValue{
-				ListValue: &proto3.ListValue{
-					Values: append(t.ListValue.Values, l.ListValue.Values...),
-				},
-			},
-		}, nil
-	default:
-		return nil, errUnsupportedMergeType(a)
-	}
-
-}
-
-// Done returns if partialResultSetDecoder has already done with all buffered
-// values.
-func (p *partialResultSetDecoder) done() bool {
-	// There is no explicit end of stream marker, but ending part way
-	// through a row is obviously bad, or ending with the last column still
-	// awaiting completion.
-	return len(p.row.vals) == 0 && !p.chunked
-}
diff --git a/vendor/cloud.google.com/go/spanner/read_test.go b/vendor/cloud.google.com/go/spanner/read_test.go
deleted file mode 100644
index db50110ab..000000000
--- a/vendor/cloud.google.com/go/spanner/read_test.go
+++ /dev/null
@@ -1,1733 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"errors"
-	"fmt"
-	"io"
-	"reflect"
-	"sync/atomic"
-	"testing"
-	"time"
-
-	"golang.org/x/net/context"
-
-	proto "github.com/golang/protobuf/proto"
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-
-	"cloud.google.com/go/spanner/internal/testutil"
-	"google.golang.org/api/iterator"
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
-)
-
-var (
-	// Mocked transaction timestamp.
-	trxTs = time.Unix(1, 2)
-	// Metadata for mocked KV table, its rows are returned by SingleUse transactions.
-	kvMeta = func() *sppb.ResultSetMetadata {
-		meta := testutil.KvMeta
-		meta.Transaction = &sppb.Transaction{
-			ReadTimestamp: timestampProto(trxTs),
-		}
-		return &meta
-	}()
-	// Metadata for mocked ListKV table, which uses List for its key and value.
-	// Its rows are returned by snapshot readonly transactions, as indicated in the transaction metadata.
-	kvListMeta = &sppb.ResultSetMetadata{
-		RowType: &sppb.StructType{
-			Fields: []*sppb.StructType_Field{
-				{
-					Name: "Key",
-					Type: &sppb.Type{
-						Code: sppb.TypeCode_ARRAY,
-						ArrayElementType: &sppb.Type{
-							Code: sppb.TypeCode_STRING,
-						},
-					},
-				},
-				{
-					Name: "Value",
-					Type: &sppb.Type{
-						Code: sppb.TypeCode_ARRAY,
-						ArrayElementType: &sppb.Type{
-							Code: sppb.TypeCode_STRING,
-						},
-					},
-				},
-			},
-		},
-		Transaction: &sppb.Transaction{
-			Id:            transactionID{5, 6, 7, 8, 9},
-			ReadTimestamp: timestampProto(trxTs),
-		},
-	}
-	// Metadata for mocked schema of a query result set, which has two struct
-	// columns named "Col1" and "Col2", the struct's schema is like the
-	// following:
-	//
-	//	STRUCT {
-	//		INT
-	//		LIST<STRING>
-	//	}
-	//
-	// Its rows are returned in readwrite transaction, as indicated in the transaction metadata.
-	kvObjectMeta = &sppb.ResultSetMetadata{
-		RowType: &sppb.StructType{
-			Fields: []*sppb.StructType_Field{
-				{
-					Name: "Col1",
-					Type: &sppb.Type{
-						Code: sppb.TypeCode_STRUCT,
-						StructType: &sppb.StructType{
-							Fields: []*sppb.StructType_Field{
-								{
-									Name: "foo-f1",
-									Type: &sppb.Type{
-										Code: sppb.TypeCode_INT64,
-									},
-								},
-								{
-									Name: "foo-f2",
-									Type: &sppb.Type{
-										Code: sppb.TypeCode_ARRAY,
-										ArrayElementType: &sppb.Type{
-											Code: sppb.TypeCode_STRING,
-										},
-									},
-								},
-							},
-						},
-					},
-				},
-				{
-					Name: "Col2",
-					Type: &sppb.Type{
-						Code: sppb.TypeCode_STRUCT,
-						StructType: &sppb.StructType{
-							Fields: []*sppb.StructType_Field{
-								{
-									Name: "bar-f1",
-									Type: &sppb.Type{
-										Code: sppb.TypeCode_INT64,
-									},
-								},
-								{
-									Name: "bar-f2",
-									Type: &sppb.Type{
-										Code: sppb.TypeCode_ARRAY,
-										ArrayElementType: &sppb.Type{
-											Code: sppb.TypeCode_STRING,
-										},
-									},
-								},
-							},
-						},
-					},
-				},
-			},
-		},
-		Transaction: &sppb.Transaction{
-			Id: transactionID{1, 2, 3, 4, 5},
-		},
-	}
-)
-
-// String implements fmt.stringer.
-func (r *Row) String() string {
-	return fmt.Sprintf("{fields: %s, val: %s}", r.fields, r.vals)
-}
-
-func describeRows(l []*Row) string {
-	// generate a nice test failure description
-	var s = "["
-	for i, r := range l {
-		if i != 0 {
-			s += ",\n "
-		}
-		s += fmt.Sprint(r)
-	}
-	s += "]"
-	return s
-}
-
-// Helper for generating proto3 Value_ListValue instances, making
-// test code shorter and readable.
-func genProtoListValue(v ...string) *proto3.Value_ListValue {
-	r := &proto3.Value_ListValue{
-		ListValue: &proto3.ListValue{
-			Values: []*proto3.Value{},
-		},
-	}
-	for _, e := range v {
-		r.ListValue.Values = append(
-			r.ListValue.Values,
-			&proto3.Value{
-				Kind: &proto3.Value_StringValue{StringValue: e},
-			},
-		)
-	}
-	return r
-}
-
-// Test Row generation logics of partialResultSetDecoder.
-func TestPartialResultSetDecoder(t *testing.T) {
-	restore := setMaxBytesBetweenResumeTokens()
-	defer restore()
-	var tests = []struct {
-		input    []*sppb.PartialResultSet
-		wantF    []*Row
-		wantTxID transactionID
-		wantTs   time.Time
-		wantD    bool
-	}{
-		{
-			// Empty input.
-			wantD: true,
-		},
-		// String merging examples.
-		{
-			// Single KV result.
-			input: []*sppb.PartialResultSet{
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "foo"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "bar"}},
-					},
-				},
-			},
-			wantF: []*Row{
-				{
-					fields: kvMeta.RowType.Fields,
-					vals: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "foo"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "bar"}},
-					},
-				},
-			},
-			wantTs: trxTs,
-			wantD:  true,
-		},
-		{
-			// Incomplete partial result.
-			input: []*sppb.PartialResultSet{
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "foo"}},
-					},
-				},
-			},
-			wantTs: trxTs,
-			wantD:  false,
-		},
-		{
-			// Complete splitted result.
-			input: []*sppb.PartialResultSet{
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "foo"}},
-					},
-				},
-				{
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "bar"}},
-					},
-				},
-			},
-			wantF: []*Row{
-				{
-					fields: kvMeta.RowType.Fields,
-					vals: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "foo"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "bar"}},
-					},
-				},
-			},
-			wantTs: trxTs,
-			wantD:  true,
-		},
-		{
-			// Multi-row example with splitted row in the middle.
-			input: []*sppb.PartialResultSet{
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "foo"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "bar"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "A"}},
-					},
-				},
-				{
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "1"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "B"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "2"}},
-					},
-				},
-			},
-			wantF: []*Row{
-				{
-					fields: kvMeta.RowType.Fields,
-					vals: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "foo"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "bar"}},
-					},
-				},
-				{
-					fields: kvMeta.RowType.Fields,
-					vals: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "A"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "1"}},
-					},
-				},
-				{
-					fields: kvMeta.RowType.Fields,
-					vals: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "B"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "2"}},
-					},
-				},
-			},
-			wantTs: trxTs,
-			wantD:  true,
-		},
-		{
-			// Merging example in result_set.proto.
-			input: []*sppb.PartialResultSet{
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "Hello"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "W"}},
-					},
-					ChunkedValue: true,
-				},
-				{
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "orl"}},
-					},
-					ChunkedValue: true,
-				},
-				{
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "d"}},
-					},
-				},
-			},
-			wantF: []*Row{
-				{
-					fields: kvMeta.RowType.Fields,
-					vals: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "Hello"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "World"}},
-					},
-				},
-			},
-			wantTs: trxTs,
-			wantD:  true,
-		},
-		{
-			// More complex example showing completing a merge and
-			// starting a new merge in the same partialResultSet.
-			input: []*sppb.PartialResultSet{
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "Hello"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "W"}}, // start split in value
-					},
-					ChunkedValue: true,
-				},
-				{
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "orld"}}, // complete value
-						{Kind: &proto3.Value_StringValue{StringValue: "i"}},    // start split in key
-					},
-					ChunkedValue: true,
-				},
-				{
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "s"}}, // complete key
-						{Kind: &proto3.Value_StringValue{StringValue: "not"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "a"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "qu"}}, // split in value
-					},
-					ChunkedValue: true,
-				},
-				{
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "estion"}}, // complete value
-					},
-				},
-			},
-			wantF: []*Row{
-				{
-					fields: kvMeta.RowType.Fields,
-					vals: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "Hello"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "World"}},
-					},
-				},
-				{
-					fields: kvMeta.RowType.Fields,
-					vals: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "is"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "not"}},
-					},
-				},
-				{
-					fields: kvMeta.RowType.Fields,
-					vals: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: "a"}},
-						{Kind: &proto3.Value_StringValue{StringValue: "question"}},
-					},
-				},
-			},
-			wantTs: trxTs,
-			wantD:  true,
-		},
-		// List merging examples.
-		{
-			// Non-splitting Lists.
-			input: []*sppb.PartialResultSet{
-				{
-					Metadata: kvListMeta,
-					Values: []*proto3.Value{
-						{
-							Kind: genProtoListValue("foo-1", "foo-2"),
-						},
-					},
-				},
-				{
-					Values: []*proto3.Value{
-						{
-							Kind: genProtoListValue("bar-1", "bar-2"),
-						},
-					},
-				},
-			},
-			wantF: []*Row{
-				{
-					fields: kvListMeta.RowType.Fields,
-					vals: []*proto3.Value{
-						{
-							Kind: genProtoListValue("foo-1", "foo-2"),
-						},
-						{
-							Kind: genProtoListValue("bar-1", "bar-2"),
-						},
-					},
-				},
-			},
-			wantTxID: transactionID{5, 6, 7, 8, 9},
-			wantTs:   trxTs,
-			wantD:    true,
-		},
-		{
-			// Simple List merge case: splitted string element.
-			input: []*sppb.PartialResultSet{
-				{
-					Metadata: kvListMeta,
-					Values: []*proto3.Value{
-						{
-							Kind: genProtoListValue("foo-1", "foo-"),
-						},
-					},
-					ChunkedValue: true,
-				},
-				{
-					Values: []*proto3.Value{
-						{
-							Kind: genProtoListValue("2"),
-						},
-					},
-				},
-				{
-					Values: []*proto3.Value{
-						{
-							Kind: genProtoListValue("bar-1", "bar-2"),
-						},
-					},
-				},
-			},
-			wantF: []*Row{
-				{
-					fields: kvListMeta.RowType.Fields,
-					vals: []*proto3.Value{
-						{
-							Kind: genProtoListValue("foo-1", "foo-2"),
-						},
-						{
-							Kind: genProtoListValue("bar-1", "bar-2"),
-						},
-					},
-				},
-			},
-			wantTxID: transactionID{5, 6, 7, 8, 9},
-			wantTs:   trxTs,
-			wantD:    true,
-		},
-		{
-			// Struct merging is also implemented by List merging. Note that
-			// Cloud Spanner uses proto.ListValue to encode Structs as well.
-			input: []*sppb.PartialResultSet{
-				{
-					Metadata: kvObjectMeta,
-					Values: []*proto3.Value{
-						{
-							Kind: &proto3.Value_ListValue{
-								ListValue: &proto3.ListValue{
-									Values: []*proto3.Value{
-										{Kind: &proto3.Value_NumberValue{NumberValue: 23}},
-										{Kind: genProtoListValue("foo-1", "fo")},
-									},
-								},
-							},
-						},
-					},
-					ChunkedValue: true,
-				},
-				{
-					Values: []*proto3.Value{
-						{
-							Kind: &proto3.Value_ListValue{
-								ListValue: &proto3.ListValue{
-									Values: []*proto3.Value{
-										{Kind: genProtoListValue("o-2", "f")},
-									},
-								},
-							},
-						},
-					},
-					ChunkedValue: true,
-				},
-				{
-					Values: []*proto3.Value{
-						{
-							Kind: &proto3.Value_ListValue{
-								ListValue: &proto3.ListValue{
-									Values: []*proto3.Value{
-										{Kind: genProtoListValue("oo-3")},
-									},
-								},
-							},
-						},
-						{
-							Kind: &proto3.Value_ListValue{
-								ListValue: &proto3.ListValue{
-									Values: []*proto3.Value{
-										{Kind: &proto3.Value_NumberValue{NumberValue: 45}},
-										{Kind: genProtoListValue("bar-1")},
-									},
-								},
-							},
-						},
-					},
-				},
-			},
-			wantF: []*Row{
-				{
-					fields: kvObjectMeta.RowType.Fields,
-					vals: []*proto3.Value{
-						{
-							Kind: &proto3.Value_ListValue{
-								ListValue: &proto3.ListValue{
-									Values: []*proto3.Value{
-										{Kind: &proto3.Value_NumberValue{NumberValue: 23}},
-										{Kind: genProtoListValue("foo-1", "foo-2", "foo-3")},
-									},
-								},
-							},
-						},
-						{
-							Kind: &proto3.Value_ListValue{
-								ListValue: &proto3.ListValue{
-									Values: []*proto3.Value{
-										{Kind: &proto3.Value_NumberValue{NumberValue: 45}},
-										{Kind: genProtoListValue("bar-1")},
-									},
-								},
-							},
-						},
-					},
-				},
-			},
-			wantTxID: transactionID{1, 2, 3, 4, 5},
-			wantD:    true,
-		},
-	}
-
-nextTest:
-	for i, test := range tests {
-		var rows []*Row
-		p := &partialResultSetDecoder{}
-		for j, v := range test.input {
-			rs, err := p.add(v)
-			if err != nil {
-				t.Errorf("test %d.%d: partialResultSetDecoder.add(%v) = %v; want nil", i, j, v, err)
-				continue nextTest
-			}
-			rows = append(rows, rs...)
-		}
-		if !reflect.DeepEqual(p.ts, test.wantTs) {
-			t.Errorf("got transaction(%v), want %v", p.ts, test.wantTs)
-		}
-		if !reflect.DeepEqual(rows, test.wantF) {
-			t.Errorf("test %d: rows=\n%v\n; want\n%v\n; p.row:\n%v\n", i, describeRows(rows), describeRows(test.wantF), p.row)
-		}
-		if got := p.done(); got != test.wantD {
-			t.Errorf("test %d: partialResultSetDecoder.done() = %v", i, got)
-		}
-	}
-}
-
-const (
-	maxBuffers = 16 // max number of PartialResultSets that will be buffered in tests.
-)
-
-// setMaxBytesBetweenResumeTokens sets the global maxBytesBetweenResumeTokens to a smaller
-// value more suitable for tests. It returns a function which should be called to restore
-// the maxBytesBetweenResumeTokens to its old value
-func setMaxBytesBetweenResumeTokens() func() {
-	o := atomic.LoadInt32(&maxBytesBetweenResumeTokens)
-	atomic.StoreInt32(&maxBytesBetweenResumeTokens, int32(maxBuffers*proto.Size(&sppb.PartialResultSet{
-		Metadata: kvMeta,
-		Values: []*proto3.Value{
-			{Kind: &proto3.Value_StringValue{StringValue: keyStr(0)}},
-			{Kind: &proto3.Value_StringValue{StringValue: valStr(0)}},
-		},
-	})))
-	return func() {
-		atomic.StoreInt32(&maxBytesBetweenResumeTokens, o)
-	}
-}
-
-// keyStr generates key string for kvMeta schema.
-func keyStr(i int) string {
-	return fmt.Sprintf("foo-%02d", i)
-}
-
-// valStr generates value string for kvMeta schema.
-func valStr(i int) string {
-	return fmt.Sprintf("bar-%02d", i)
-}
-
-// Test state transitions of resumableStreamDecoder where state machine
-// ends up to a non-blocking state(resumableStreamDecoder.Next returns
-// on non-blocking state).
-func TestRsdNonblockingStates(t *testing.T) {
-	restore := setMaxBytesBetweenResumeTokens()
-	defer restore()
-	tests := []struct {
-		name string
-		msgs []testutil.MockCtlMsg
-		rpc  func(ct context.Context, resumeToken []byte) (streamingReceiver, error)
-		sql  string
-		// Expected values
-		want         []*sppb.PartialResultSet      // PartialResultSets that should be returned to caller
-		queue        []*sppb.PartialResultSet      // PartialResultSets that should be buffered
-		resumeToken  []byte                        // Resume token that is maintained by resumableStreamDecoder
-		stateHistory []resumableStreamDecoderState // State transition history of resumableStreamDecoder
-		wantErr      error
-	}{
-		{
-			// unConnected->queueingRetryable->finished
-			name: "unConnected->queueingRetryable->finished",
-			msgs: []testutil.MockCtlMsg{
-				{},
-				{},
-				{Err: io.EOF, ResumeToken: false},
-			},
-			sql: "SELECT t.key key, t.value value FROM t_mock t",
-			want: []*sppb.PartialResultSet{
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: keyStr(0)}},
-						{Kind: &proto3.Value_StringValue{StringValue: valStr(0)}},
-					},
-				},
-			},
-			queue: []*sppb.PartialResultSet{
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: keyStr(1)}},
-						{Kind: &proto3.Value_StringValue{StringValue: valStr(1)}},
-					},
-				},
-			},
-			stateHistory: []resumableStreamDecoderState{
-				queueingRetryable, // do RPC
-				queueingRetryable, // got foo-00
-				queueingRetryable, // got foo-01
-				finished,          // got EOF
-			},
-		},
-		{
-			// unConnected->queueingRetryable->aborted
-			name: "unConnected->queueingRetryable->aborted",
-			msgs: []testutil.MockCtlMsg{
-				{},
-				{Err: nil, ResumeToken: true},
-				{},
-				{Err: errors.New("I quit"), ResumeToken: false},
-			},
-			sql: "SELECT t.key key, t.value value FROM t_mock t",
-			want: []*sppb.PartialResultSet{
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: keyStr(0)}},
-						{Kind: &proto3.Value_StringValue{StringValue: valStr(0)}},
-					},
-				},
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: keyStr(1)}},
-						{Kind: &proto3.Value_StringValue{StringValue: valStr(1)}},
-					},
-					ResumeToken: testutil.EncodeResumeToken(1),
-				},
-			},
-			stateHistory: []resumableStreamDecoderState{
-				queueingRetryable, // do RPC
-				queueingRetryable, // got foo-00
-				queueingRetryable, // got foo-01
-				queueingRetryable, // foo-01, resume token
-				queueingRetryable, // got foo-02
-				aborted,           // got error
-			},
-			wantErr: grpc.Errorf(codes.Unknown, "I quit"),
-		},
-		{
-			// unConnected->queueingRetryable->queueingUnretryable->queueingUnretryable
-			name: "unConnected->queueingRetryable->queueingUnretryable->queueingUnretryable",
-			msgs: func() (m []testutil.MockCtlMsg) {
-				for i := 0; i < maxBuffers+1; i++ {
-					m = append(m, testutil.MockCtlMsg{})
-				}
-				return m
-			}(),
-			sql: "SELECT t.key key, t.value value FROM t_mock t",
-			want: func() (s []*sppb.PartialResultSet) {
-				for i := 0; i < maxBuffers+1; i++ {
-					s = append(s, &sppb.PartialResultSet{
-						Metadata: kvMeta,
-						Values: []*proto3.Value{
-							{Kind: &proto3.Value_StringValue{StringValue: keyStr(i)}},
-							{Kind: &proto3.Value_StringValue{StringValue: valStr(i)}},
-						},
-					})
-				}
-				return s
-			}(),
-			stateHistory: func() (s []resumableStreamDecoderState) {
-				s = append(s, queueingRetryable) // RPC
-				for i := 0; i < maxBuffers; i++ {
-					s = append(s, queueingRetryable) // the internal queue of resumableStreamDecoder fills up
-				}
-				// the first item fills up the queue and triggers state transition;
-				// the second item is received under queueingUnretryable state.
-				s = append(s, queueingUnretryable)
-				s = append(s, queueingUnretryable)
-				return s
-			}(),
-		},
-		{
-			// unConnected->queueingRetryable->queueingUnretryable->aborted
-			name: "unConnected->queueingRetryable->queueingUnretryable->aborted",
-			msgs: func() (m []testutil.MockCtlMsg) {
-				for i := 0; i < maxBuffers; i++ {
-					m = append(m, testutil.MockCtlMsg{})
-				}
-				m = append(m, testutil.MockCtlMsg{Err: errors.New("Just Abort It"), ResumeToken: false})
-				return m
-			}(),
-			sql: "SELECT t.key key, t.value value FROM t_mock t",
-			want: func() (s []*sppb.PartialResultSet) {
-				for i := 0; i < maxBuffers; i++ {
-					s = append(s, &sppb.PartialResultSet{
-						Metadata: kvMeta,
-						Values: []*proto3.Value{
-							{Kind: &proto3.Value_StringValue{StringValue: keyStr(i)}},
-							{Kind: &proto3.Value_StringValue{StringValue: valStr(i)}},
-						},
-					})
-				}
-				return s
-			}(),
-			stateHistory: func() (s []resumableStreamDecoderState) {
-				s = append(s, queueingRetryable) // RPC
-				for i := 0; i < maxBuffers; i++ {
-					s = append(s, queueingRetryable) // internal queue of resumableStreamDecoder fills up
-				}
-				s = append(s, queueingUnretryable) // the last row triggers state change
-				s = append(s, aborted)             // Error happens
-				return s
-			}(),
-			wantErr: grpc.Errorf(codes.Unknown, "Just Abort It"),
-		},
-	}
-nextTest:
-	for _, test := range tests {
-		ms := testutil.NewMockCloudSpanner(t, trxTs)
-		ms.Serve()
-		opts := []grpc.DialOption{
-			grpc.WithInsecure(),
-		}
-		cc, err := grpc.Dial(ms.Addr(), opts...)
-		if err != nil {
-			t.Fatalf("%v: Dial(%q) = %v", test.name, ms.Addr(), err)
-		}
-		mc := sppb.NewSpannerClient(cc)
-		if test.rpc == nil {
-			test.rpc = func(ct context.Context, resumeToken []byte) (streamingReceiver, error) {
-				return mc.ExecuteStreamingSql(ct, &sppb.ExecuteSqlRequest{
-					Sql:         test.sql,
-					ResumeToken: resumeToken,
-				})
-			}
-		}
-		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
-		defer cancel()
-		r := newResumableStreamDecoder(
-			ctx,
-			test.rpc,
-		)
-		st := []resumableStreamDecoderState{}
-		var lastErr error
-		// Once the expected number of state transitions are observed,
-		// send a signal by setting stateDone = true.
-		stateDone := false
-		// Set stateWitness to listen to state changes.
-		hl := len(test.stateHistory) // To avoid data race on test.
-		r.stateWitness = func(rs resumableStreamDecoderState) {
-			if !stateDone {
-				// Record state transitions.
-				st = append(st, rs)
-				if len(st) == hl {
-					lastErr = r.lastErr()
-					stateDone = true
-				}
-			}
-		}
-		// Let mock server stream given messages to resumableStreamDecoder.
-		for _, m := range test.msgs {
-			ms.AddMsg(m.Err, m.ResumeToken)
-		}
-		var rs []*sppb.PartialResultSet
-		for {
-			select {
-			case <-ctx.Done():
-				t.Errorf("context cancelled or timeout during test")
-				continue nextTest
-			default:
-			}
-			if stateDone {
-				// Check if resumableStreamDecoder carried out expected
-				// state transitions.
-				if !reflect.DeepEqual(st, test.stateHistory) {
-					t.Errorf("%v: observed state transitions: \n%v\n, want \n%v\n",
-						test.name, st, test.stateHistory)
-				}
-				// Check if resumableStreamDecoder returns expected array of
-				// PartialResultSets.
-				if !reflect.DeepEqual(rs, test.want) {
-					t.Errorf("%v: received PartialResultSets: \n%v\n, want \n%v\n", test.name, rs, test.want)
-				}
-				// Verify that resumableStreamDecoder's internal buffering is also correct.
-				var q []*sppb.PartialResultSet
-				for {
-					item := r.q.pop()
-					if item == nil {
-						break
-					}
-					q = append(q, item)
-				}
-				if !reflect.DeepEqual(q, test.queue) {
-					t.Errorf("%v: PartialResultSets still queued: \n%v\n, want \n%v\n", test.name, q, test.queue)
-				}
-				// Verify resume token.
-				if test.resumeToken != nil && !reflect.DeepEqual(r.resumeToken, test.resumeToken) {
-					t.Errorf("%v: Resume token is %v, want %v\n", test.name, r.resumeToken, test.resumeToken)
-				}
-				// Verify error message.
-				if !reflect.DeepEqual(lastErr, test.wantErr) {
-					t.Errorf("%v: got error %v, want %v", test.name, lastErr, test.wantErr)
-				}
-				// Proceed to next test
-				continue nextTest
-			}
-			// Receive next decoded item.
-			if r.next() {
-				rs = append(rs, r.get())
-			}
-		}
-	}
-}
-
-// Test state transitions of resumableStreamDecoder where state machine
-// ends up to a blocking state(resumableStreamDecoder.Next blocks
-// on blocking state).
-func TestRsdBlockingStates(t *testing.T) {
-	restore := setMaxBytesBetweenResumeTokens()
-	defer restore()
-	tests := []struct {
-		name string
-		msgs []testutil.MockCtlMsg
-		rpc  func(ct context.Context, resumeToken []byte) (streamingReceiver, error)
-		sql  string
-		// Expected values
-		want         []*sppb.PartialResultSet      // PartialResultSets that should be returned to caller
-		queue        []*sppb.PartialResultSet      // PartialResultSets that should be buffered
-		resumeToken  []byte                        // Resume token that is maintained by resumableStreamDecoder
-		stateHistory []resumableStreamDecoderState // State transition history of resumableStreamDecoder
-		wantErr      error
-	}{
-		{
-			// unConnected -> unConnected
-			name: "unConnected -> unConnected",
-			rpc: func(ct context.Context, resumeToken []byte) (streamingReceiver, error) {
-				return nil, grpc.Errorf(codes.Unavailable, "trust me: server is unavailable")
-			},
-			sql:          "SELECT * from t_whatever",
-			stateHistory: []resumableStreamDecoderState{unConnected, unConnected, unConnected},
-			wantErr:      grpc.Errorf(codes.Unavailable, "trust me: server is unavailable"),
-		},
-		{
-			// unConnected -> queueingRetryable
-			name:         "unConnected -> queueingRetryable",
-			sql:          "SELECT t.key key, t.value value FROM t_mock t",
-			stateHistory: []resumableStreamDecoderState{queueingRetryable},
-		},
-		{
-			// unConnected->queueingRetryable->queueingRetryable
-			name: "unConnected->queueingRetryable->queueingRetryable",
-			msgs: []testutil.MockCtlMsg{
-				{},
-				{Err: nil, ResumeToken: true},
-				{Err: nil, ResumeToken: true},
-				{},
-			},
-			sql: "SELECT t.key key, t.value value FROM t_mock t",
-			want: []*sppb.PartialResultSet{
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: keyStr(0)}},
-						{Kind: &proto3.Value_StringValue{StringValue: valStr(0)}},
-					},
-				},
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: keyStr(1)}},
-						{Kind: &proto3.Value_StringValue{StringValue: valStr(1)}},
-					},
-					ResumeToken: testutil.EncodeResumeToken(1),
-				},
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: keyStr(2)}},
-						{Kind: &proto3.Value_StringValue{StringValue: valStr(2)}},
-					},
-					ResumeToken: testutil.EncodeResumeToken(2),
-				},
-			},
-			queue: []*sppb.PartialResultSet{
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: keyStr(3)}},
-						{Kind: &proto3.Value_StringValue{StringValue: valStr(3)}},
-					},
-				},
-			},
-			resumeToken: testutil.EncodeResumeToken(2),
-			stateHistory: []resumableStreamDecoderState{
-				queueingRetryable, // do RPC
-				queueingRetryable, // got foo-00
-				queueingRetryable, // got foo-01
-				queueingRetryable, // foo-01, resume token
-				queueingRetryable, // got foo-02
-				queueingRetryable, // foo-02, resume token
-				queueingRetryable, // got foo-03
-			},
-		},
-		{
-			// unConnected->queueingRetryable->queueingUnretryable->queueingRetryable->queueingRetryable
-			name: "unConnected->queueingRetryable->queueingUnretryable->queueingRetryable->queueingRetryable",
-			msgs: func() (m []testutil.MockCtlMsg) {
-				for i := 0; i < maxBuffers+1; i++ {
-					m = append(m, testutil.MockCtlMsg{})
-				}
-				m = append(m, testutil.MockCtlMsg{Err: nil, ResumeToken: true})
-				m = append(m, testutil.MockCtlMsg{})
-				return m
-			}(),
-			sql: "SELECT t.key key, t.value value FROM t_mock t",
-			want: func() (s []*sppb.PartialResultSet) {
-				for i := 0; i < maxBuffers+2; i++ {
-					s = append(s, &sppb.PartialResultSet{
-						Metadata: kvMeta,
-						Values: []*proto3.Value{
-							{Kind: &proto3.Value_StringValue{StringValue: keyStr(i)}},
-							{Kind: &proto3.Value_StringValue{StringValue: valStr(i)}},
-						},
-					})
-				}
-				s[maxBuffers+1].ResumeToken = testutil.EncodeResumeToken(maxBuffers + 1)
-				return s
-			}(),
-			resumeToken: testutil.EncodeResumeToken(maxBuffers + 1),
-			queue: []*sppb.PartialResultSet{
-				{
-					Metadata: kvMeta,
-					Values: []*proto3.Value{
-						{Kind: &proto3.Value_StringValue{StringValue: keyStr(maxBuffers + 2)}},
-						{Kind: &proto3.Value_StringValue{StringValue: valStr(maxBuffers + 2)}},
-					},
-				},
-			},
-			stateHistory: func() (s []resumableStreamDecoderState) {
-				s = append(s, queueingRetryable) // RPC
-				for i := 0; i < maxBuffers; i++ {
-					s = append(s, queueingRetryable) // internal queue of resumableStreamDecoder filles up
-				}
-				for i := maxBuffers - 1; i < maxBuffers+1; i++ {
-					// the first item fills up the queue and triggers state change;
-					// the second item is received under queueingUnretryable state.
-					s = append(s, queueingUnretryable)
-				}
-				s = append(s, queueingUnretryable) // got (maxBuffers+1)th row under Unretryable state
-				s = append(s, queueingRetryable)   // (maxBuffers+1)th row has resume token
-				s = append(s, queueingRetryable)   // (maxBuffers+2)th row has no resume token
-				return s
-			}(),
-		},
-		{
-			// unConnected->queueingRetryable->queueingUnretryable->finished
-			name: "unConnected->queueingRetryable->queueingUnretryable->finished",
-			msgs: func() (m []testutil.MockCtlMsg) {
-				for i := 0; i < maxBuffers; i++ {
-					m = append(m, testutil.MockCtlMsg{})
-				}
-				m = append(m, testutil.MockCtlMsg{Err: io.EOF, ResumeToken: false})
-				return m
-			}(),
-			sql: "SELECT t.key key, t.value value FROM t_mock t",
-			want: func() (s []*sppb.PartialResultSet) {
-				for i := 0; i < maxBuffers; i++ {
-					s = append(s, &sppb.PartialResultSet{
-						Metadata: kvMeta,
-						Values: []*proto3.Value{
-							{Kind: &proto3.Value_StringValue{StringValue: keyStr(i)}},
-							{Kind: &proto3.Value_StringValue{StringValue: valStr(i)}},
-						},
-					})
-				}
-				return s
-			}(),
-			stateHistory: func() (s []resumableStreamDecoderState) {
-				s = append(s, queueingRetryable) // RPC
-				for i := 0; i < maxBuffers; i++ {
-					s = append(s, queueingRetryable) // internal queue of resumableStreamDecoder fills up
-				}
-				s = append(s, queueingUnretryable) // last row triggers state change
-				s = append(s, finished)            // query finishes
-				return s
-			}(),
-		},
-	}
-	for _, test := range tests {
-		ms := testutil.NewMockCloudSpanner(t, trxTs)
-		ms.Serve()
-		opts := []grpc.DialOption{
-			grpc.WithInsecure(),
-		}
-		cc, err := grpc.Dial(ms.Addr(), opts...)
-		if err != nil {
-			t.Fatalf("%v: Dial(%q) = %v", test.name, ms.Addr(), err)
-		}
-		mc := sppb.NewSpannerClient(cc)
-		if test.rpc == nil {
-			// Avoid using test.sql directly in closure because for loop changes test.
-			sql := test.sql
-			test.rpc = func(ct context.Context, resumeToken []byte) (streamingReceiver, error) {
-				return mc.ExecuteStreamingSql(ct, &sppb.ExecuteSqlRequest{
-					Sql:         sql,
-					ResumeToken: resumeToken,
-				})
-			}
-		}
-		ctx, cancel := context.WithCancel(context.Background())
-		defer cancel()
-		r := newResumableStreamDecoder(
-			ctx,
-			test.rpc,
-		)
-		// Override backoff to make the test run faster.
-		r.backoff = exponentialBackoff{1 * time.Nanosecond, 1 * time.Nanosecond}
-		// st is the set of observed state transitions.
-		st := []resumableStreamDecoderState{}
-		// q is the content of the decoder's partial result queue when expected number of state transitions are done.
-		q := []*sppb.PartialResultSet{}
-		var lastErr error
-		// Once the expected number of state transitions are observed,
-		// send a signal to channel stateDone.
-		stateDone := make(chan int)
-		// Set stateWitness to listen to state changes.
-		hl := len(test.stateHistory) // To avoid data race on test.
-		r.stateWitness = func(rs resumableStreamDecoderState) {
-			select {
-			case <-stateDone:
-				// Noop after expected number of state transitions
-			default:
-				// Record state transitions.
-				st = append(st, rs)
-				if len(st) == hl {
-					lastErr = r.lastErr()
-					q = r.q.dump()
-					close(stateDone)
-				}
-			}
-		}
-		// Let mock server stream given messages to resumableStreamDecoder.
-		for _, m := range test.msgs {
-			ms.AddMsg(m.Err, m.ResumeToken)
-		}
-		var rs []*sppb.PartialResultSet
-		go func() {
-			for {
-				if !r.next() {
-					// Note that r.Next also exits on context cancel/timeout.
-					return
-				}
-				rs = append(rs, r.get())
-			}
-		}()
-		// Verify that resumableStreamDecoder reaches expected state.
-		select {
-		case <-stateDone: // Note that at this point, receiver is still blocking on r.next().
-			// Check if resumableStreamDecoder carried out expected
-			// state transitions.
-			if !reflect.DeepEqual(st, test.stateHistory) {
-				t.Errorf("%v: observed state transitions: \n%v\n, want \n%v\n",
-					test.name, st, test.stateHistory)
-			}
-			// Check if resumableStreamDecoder returns expected array of
-			// PartialResultSets.
-			if !reflect.DeepEqual(rs, test.want) {
-				t.Errorf("%v: received PartialResultSets: \n%v\n, want \n%v\n", test.name, rs, test.want)
-			}
-			// Verify that resumableStreamDecoder's internal buffering is also correct.
-			if !reflect.DeepEqual(q, test.queue) {
-				t.Errorf("%v: PartialResultSets still queued: \n%v\n, want \n%v\n", test.name, q, test.queue)
-			}
-			// Verify resume token.
-			if test.resumeToken != nil && !reflect.DeepEqual(r.resumeToken, test.resumeToken) {
-				t.Errorf("%v: Resume token is %v, want %v\n", test.name, r.resumeToken, test.resumeToken)
-			}
-			// Verify error message.
-			if !reflect.DeepEqual(lastErr, test.wantErr) {
-				t.Errorf("%v: got error %v, want %v", test.name, lastErr, test.wantErr)
-			}
-		case <-time.After(1 * time.Second):
-			t.Errorf("%v: Timeout in waiting for state change", test.name)
-		}
-		ms.Stop()
-		cc.Close()
-	}
-}
-
-// sReceiver signals every receiving attempt through a channel,
-// used by TestResumeToken to determine if the receiving of a certain
-// PartialResultSet will be attempted next.
-type sReceiver struct {
-	c           chan int
-	rpcReceiver sppb.Spanner_ExecuteStreamingSqlClient
-}
-
-// Recv() implements streamingReceiver.Recv for sReceiver.
-func (sr *sReceiver) Recv() (*sppb.PartialResultSet, error) {
-	sr.c <- 1
-	return sr.rpcReceiver.Recv()
-}
-
-// waitn waits for nth receiving attempt from now on, until
-// the signal for nth Recv() attempts is received or timeout.
-// Note that because the way stream() works, the signal for the
-// nth Recv() means that the previous n - 1 PartialResultSets
-// has already been returned to caller or queued, if no error happened.
-func (sr *sReceiver) waitn(n int) error {
-	for i := 0; i < n; i++ {
-		select {
-		case <-sr.c:
-		case <-time.After(10 * time.Second):
-			return fmt.Errorf("timeout in waiting for %v-th Recv()", i+1)
-		}
-	}
-	return nil
-}
-
-// Test the handling of resumableStreamDecoder.bytesBetweenResumeTokens.
-func TestQueueBytes(t *testing.T) {
-	restore := setMaxBytesBetweenResumeTokens()
-	defer restore()
-	ms := testutil.NewMockCloudSpanner(t, trxTs)
-	ms.Serve()
-	defer ms.Stop()
-	opts := []grpc.DialOption{
-		grpc.WithInsecure(),
-	}
-	cc, err := grpc.Dial(ms.Addr(), opts...)
-	if err != nil {
-		t.Fatalf("Dial(%q) = %v", ms.Addr(), err)
-	}
-	defer cc.Close()
-	mc := sppb.NewSpannerClient(cc)
-	sr := &sReceiver{
-		c: make(chan int, 1000), // will never block in this test
-	}
-	wantQueueBytes := 0
-	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
-	defer cancel()
-	r := newResumableStreamDecoder(
-		ctx,
-		func(ct context.Context, resumeToken []byte) (streamingReceiver, error) {
-			r, err := mc.ExecuteStreamingSql(ct, &sppb.ExecuteSqlRequest{
-				Sql:         "SELECT t.key key, t.value value FROM t_mock t",
-				ResumeToken: resumeToken,
-			})
-			sr.rpcReceiver = r
-			return sr, err
-		},
-	)
-	go func() {
-		for r.next() {
-		}
-	}()
-	// Let server send maxBuffers / 2 rows.
-	for i := 0; i < maxBuffers/2; i++ {
-		wantQueueBytes += proto.Size(&sppb.PartialResultSet{
-			Metadata: kvMeta,
-			Values: []*proto3.Value{
-				{Kind: &proto3.Value_StringValue{StringValue: keyStr(i)}},
-				{Kind: &proto3.Value_StringValue{StringValue: valStr(i)}},
-			},
-		})
-		ms.AddMsg(nil, false)
-	}
-	if err := sr.waitn(maxBuffers/2 + 1); err != nil {
-		t.Fatalf("failed to wait for the first %v recv() calls: %v", maxBuffers, err)
-	}
-	if int32(wantQueueBytes) != r.bytesBetweenResumeTokens {
-		t.Errorf("r.bytesBetweenResumeTokens = %v, want %v", r.bytesBetweenResumeTokens, wantQueueBytes)
-	}
-	// Now send a resume token to drain the queue.
-	ms.AddMsg(nil, true)
-	// Wait for all rows to be processes.
-	if err := sr.waitn(1); err != nil {
-		t.Fatalf("failed to wait for rows to be processed: %v", err)
-	}
-	if r.bytesBetweenResumeTokens != 0 {
-		t.Errorf("r.bytesBetweenResumeTokens = %v, want 0", r.bytesBetweenResumeTokens)
-	}
-	// Let server send maxBuffers - 1 rows.
-	wantQueueBytes = 0
-	for i := 0; i < maxBuffers-1; i++ {
-		wantQueueBytes += proto.Size(&sppb.PartialResultSet{
-			Metadata: kvMeta,
-			Values: []*proto3.Value{
-				{Kind: &proto3.Value_StringValue{StringValue: keyStr(i)}},
-				{Kind: &proto3.Value_StringValue{StringValue: valStr(i)}},
-			},
-		})
-		ms.AddMsg(nil, false)
-	}
-	if err := sr.waitn(maxBuffers - 1); err != nil {
-		t.Fatalf("failed to wait for %v rows to be processed: %v", maxBuffers-1, err)
-	}
-	if int32(wantQueueBytes) != r.bytesBetweenResumeTokens {
-		t.Errorf("r.bytesBetweenResumeTokens = %v, want 0", r.bytesBetweenResumeTokens)
-	}
-	// Trigger a state transition: queueingRetryable -> queueingUnretryable.
-	ms.AddMsg(nil, false)
-	if err := sr.waitn(1); err != nil {
-		t.Fatalf("failed to wait for state transition: %v", err)
-	}
-	if r.bytesBetweenResumeTokens != 0 {
-		t.Errorf("r.bytesBetweenResumeTokens = %v, want 0", r.bytesBetweenResumeTokens)
-	}
-}
-
-// Verify that client can deal with resume token correctly
-func TestResumeToken(t *testing.T) {
-	restore := setMaxBytesBetweenResumeTokens()
-	defer restore()
-	ms := testutil.NewMockCloudSpanner(t, trxTs)
-	ms.Serve()
-	opts := []grpc.DialOption{
-		grpc.WithInsecure(),
-	}
-	cc, err := grpc.Dial(ms.Addr(), opts...)
-	if err != nil {
-		t.Fatalf("Dial(%q) = %v", ms.Addr(), err)
-	}
-	defer func() {
-		ms.Stop()
-		cc.Close()
-	}()
-	mc := sppb.NewSpannerClient(cc)
-	sr := &sReceiver{
-		c: make(chan int, 1000), // will never block in this test
-	}
-	rows := []*Row{}
-	done := make(chan int)
-	streaming := func() {
-		// Establish a stream to mock cloud spanner server.
-		iter := stream(context.Background(),
-			func(ct context.Context, resumeToken []byte) (streamingReceiver, error) {
-				r, err := mc.ExecuteStreamingSql(ct, &sppb.ExecuteSqlRequest{
-					Sql:         "SELECT t.key key, t.value value FROM t_mock t",
-					ResumeToken: resumeToken,
-				})
-				sr.rpcReceiver = r
-				return sr, err
-			},
-			nil,
-			func(error) {})
-		defer iter.Stop()
-		for {
-			var row *Row
-			row, err = iter.Next()
-			if err == iterator.Done {
-				err = nil
-				break
-			}
-			if err != nil {
-				break
-			}
-			rows = append(rows, row)
-		}
-		done <- 1
-	}
-	go streaming()
-	// Server streaming row 0 - 2, only row 1 has resume token.
-	// Client will receive row 0 - 2, so it will try receiving for
-	// 4 times (the last recv will block), and only row 0 - 1 will
-	// be yielded.
-	for i := 0; i < 3; i++ {
-		if i == 1 {
-			ms.AddMsg(nil, true)
-		} else {
-			ms.AddMsg(nil, false)
-		}
-	}
-	// Wait for 4 receive attempts, as explained above.
-	if err = sr.waitn(4); err != nil {
-		t.Fatalf("failed to wait for row 0 - 2: %v", err)
-	}
-	want := []*Row{
-		{
-			fields: kvMeta.RowType.Fields,
-			vals: []*proto3.Value{
-				{Kind: &proto3.Value_StringValue{StringValue: keyStr(0)}},
-				{Kind: &proto3.Value_StringValue{StringValue: valStr(0)}},
-			},
-		},
-		{
-			fields: kvMeta.RowType.Fields,
-			vals: []*proto3.Value{
-				{Kind: &proto3.Value_StringValue{StringValue: keyStr(1)}},
-				{Kind: &proto3.Value_StringValue{StringValue: valStr(1)}},
-			},
-		},
-	}
-	if !reflect.DeepEqual(rows, want) {
-		t.Errorf("received rows: \n%v\n; but want\n%v\n", rows, want)
-	}
-	// Inject resumable failure.
-	ms.AddMsg(
-		grpc.Errorf(codes.Unavailable, "mock server unavailable"),
-		false,
-	)
-	// Test if client detects the resumable failure and retries.
-	if err = sr.waitn(1); err != nil {
-		t.Fatalf("failed to wait for client to retry: %v", err)
-	}
-	// Client has resumed the query, now server resend row 2.
-	ms.AddMsg(nil, true)
-	if err = sr.waitn(1); err != nil {
-		t.Fatalf("failed to wait for resending row 2: %v", err)
-	}
-	// Now client should have received row 0 - 2.
-	want = append(want, &Row{
-		fields: kvMeta.RowType.Fields,
-		vals: []*proto3.Value{
-			{Kind: &proto3.Value_StringValue{StringValue: keyStr(2)}},
-			{Kind: &proto3.Value_StringValue{StringValue: valStr(2)}},
-		},
-	})
-	if !reflect.DeepEqual(rows, want) {
-		t.Errorf("received rows: \n%v\n, want\n%v\n", rows, want)
-	}
-	// Sending 3rd - (maxBuffers+1)th rows without resume tokens, client should buffer them.
-	for i := 3; i < maxBuffers+2; i++ {
-		ms.AddMsg(nil, false)
-	}
-	if err = sr.waitn(maxBuffers - 1); err != nil {
-		t.Fatalf("failed to wait for row 3-%v: %v", maxBuffers+1, err)
-	}
-	// Received rows should be unchanged.
-	if !reflect.DeepEqual(rows, want) {
-		t.Errorf("receive rows: \n%v\n, want\n%v\n", rows, want)
-	}
-	// Send (maxBuffers+2)th row to trigger state change of resumableStreamDecoder:
-	// queueingRetryable -> queueingUnretryable
-	ms.AddMsg(nil, false)
-	if err = sr.waitn(1); err != nil {
-		t.Fatalf("failed to wait for row %v: %v", maxBuffers+2, err)
-	}
-	// Client should yield row 3rd - (maxBuffers+2)th to application. Therefore, application should
-	// see row 0 - (maxBuffers+2)th so far.
-	for i := 3; i < maxBuffers+3; i++ {
-		want = append(want, &Row{
-			fields: kvMeta.RowType.Fields,
-			vals: []*proto3.Value{
-				{Kind: &proto3.Value_StringValue{StringValue: keyStr(i)}},
-				{Kind: &proto3.Value_StringValue{StringValue: valStr(i)}},
-			},
-		})
-	}
-	if !reflect.DeepEqual(rows, want) {
-		t.Errorf("received rows: \n%v\n; want\n%v\n", rows, want)
-	}
-	// Inject resumable error, but since resumableStreamDecoder is already at queueingUnretryable
-	// state, query will just fail.
-	ms.AddMsg(
-		grpc.Errorf(codes.Unavailable, "mock server wants some sleep"),
-		false,
-	)
-	select {
-	case <-done:
-	case <-time.After(10 * time.Second):
-		t.Fatalf("timeout in waiting for failed query to return.")
-	}
-	if wantErr := toSpannerError(grpc.Errorf(codes.Unavailable, "mock server wants some sleep")); !reflect.DeepEqual(err, wantErr) {
-		t.Fatalf("stream() returns error: %v, but want error: %v", err, wantErr)
-	}
-
-	// Reconnect to mock Cloud Spanner.
-	rows = []*Row{}
-	go streaming()
-	// Let server send two rows without resume token.
-	for i := maxBuffers + 3; i < maxBuffers+5; i++ {
-		ms.AddMsg(nil, false)
-	}
-	if err = sr.waitn(3); err != nil {
-		t.Fatalf("failed to wait for row %v - %v: %v", maxBuffers+3, maxBuffers+5, err)
-	}
-	if len(rows) > 0 {
-		t.Errorf("client received some rows unexpectedly: %v, want nothing", rows)
-	}
-	// Let server end the query.
-	ms.AddMsg(io.EOF, false)
-	select {
-	case <-done:
-	case <-time.After(10 * time.Second):
-		t.Fatalf("timeout in waiting for failed query to return")
-	}
-	if err != nil {
-		t.Fatalf("stream() returns unexpected error: %v, but want no error", err)
-	}
-	// Verify if a normal server side EOF flushes all queued rows.
-	want = []*Row{
-		{
-			fields: kvMeta.RowType.Fields,
-			vals: []*proto3.Value{
-				{Kind: &proto3.Value_StringValue{StringValue: keyStr(maxBuffers + 3)}},
-				{Kind: &proto3.Value_StringValue{StringValue: valStr(maxBuffers + 3)}},
-			},
-		},
-		{
-			fields: kvMeta.RowType.Fields,
-			vals: []*proto3.Value{
-				{Kind: &proto3.Value_StringValue{StringValue: keyStr(maxBuffers + 4)}},
-				{Kind: &proto3.Value_StringValue{StringValue: valStr(maxBuffers + 4)}},
-			},
-		},
-	}
-	if !reflect.DeepEqual(rows, want) {
-		t.Errorf("received rows: \n%v\n; but want\n%v\n", rows, want)
-	}
-}
-
-// Verify that streaming query get retried upon real gRPC server transport failures.
-func TestGrpcReconnect(t *testing.T) {
-	restore := setMaxBytesBetweenResumeTokens()
-	defer restore()
-	ms := testutil.NewMockCloudSpanner(t, trxTs)
-	ms.Serve()
-	defer ms.Stop()
-	cc, err := grpc.Dial(ms.Addr(), grpc.WithInsecure())
-	if err != nil {
-		t.Fatalf("Dial(%q) = %v", ms.Addr(), err)
-	}
-	defer cc.Close()
-	mc := sppb.NewSpannerClient(cc)
-	retry := make(chan int)
-	row := make(chan int)
-	go func() {
-		r := 0
-		// Establish a stream to mock cloud spanner server.
-		iter := stream(context.Background(),
-			func(ct context.Context, resumeToken []byte) (streamingReceiver, error) {
-				if r > 0 {
-					// This RPC attempt is a retry, signal it.
-					retry <- r
-				}
-				r++
-				return mc.ExecuteStreamingSql(ct, &sppb.ExecuteSqlRequest{
-					Sql:         "SELECT t.key key, t.value value FROM t_mock t",
-					ResumeToken: resumeToken,
-				})
-
-			},
-			nil,
-			func(error) {})
-		defer iter.Stop()
-		for {
-			_, err = iter.Next()
-			if err == iterator.Done {
-				err = nil
-				break
-			}
-			if err != nil {
-				break
-			}
-			row <- 0
-		}
-	}()
-	// Add a message and wait for the receipt.
-	ms.AddMsg(nil, true)
-	select {
-	case <-row:
-	case <-time.After(10 * time.Second):
-		t.Fatalf("expect stream to be established within 10 seconds, but it didn't")
-	}
-	// Error injection: force server to close all connections.
-	ms.Stop()
-	// Test to see if client respond to the real RPC failure correctly by
-	// retrying RPC.
-	select {
-	case r, ok := <-retry:
-		if ok && r == 1 {
-			break
-		}
-		t.Errorf("retry count = %v, want 1", r)
-	case <-time.After(10 * time.Second):
-		t.Errorf("client library failed to respond after 10 seconds, aborting")
-		return
-	}
-}
-
-// Test cancel/timeout for client operations.
-func TestCancelTimeout(t *testing.T) {
-	restore := setMaxBytesBetweenResumeTokens()
-	defer restore()
-	ms := testutil.NewMockCloudSpanner(t, trxTs)
-	ms.Serve()
-	defer ms.Stop()
-	opts := []grpc.DialOption{
-		grpc.WithInsecure(),
-	}
-	cc, err := grpc.Dial(ms.Addr(), opts...)
-	defer cc.Close()
-	if err != nil {
-		t.Fatalf("Dial(%q) = %v", ms.Addr(), err)
-	}
-	mc := sppb.NewSpannerClient(cc)
-	done := make(chan int)
-	go func() {
-		for {
-			ms.AddMsg(nil, true)
-		}
-	}()
-	// Test cancelling query.
-	ctx, cancel := context.WithCancel(context.Background())
-	go func() {
-		// Establish a stream to mock cloud spanner server.
-		iter := stream(ctx,
-			func(ct context.Context, resumeToken []byte) (streamingReceiver, error) {
-				return mc.ExecuteStreamingSql(ct, &sppb.ExecuteSqlRequest{
-					Sql:         "SELECT t.key key, t.value value FROM t_mock t",
-					ResumeToken: resumeToken,
-				})
-			},
-			nil,
-			func(error) {})
-		defer iter.Stop()
-		for {
-			_, err = iter.Next()
-			if err == iterator.Done {
-				break
-			}
-			if err != nil {
-				done <- 0
-				break
-			}
-		}
-	}()
-	cancel()
-	select {
-	case <-done:
-		if ErrCode(err) != codes.Canceled {
-			t.Errorf("streaming query is canceled and returns error %v, want error code %v", err, codes.Canceled)
-		}
-	case <-time.After(1 * time.Second):
-		t.Errorf("query doesn't exit timely after being cancelled")
-	}
-	// Test query timeout.
-	ctx, cancel = context.WithTimeout(context.Background(), 1*time.Second)
-	go func() {
-		// Establish a stream to mock cloud spanner server.
-		iter := stream(ctx,
-			func(ct context.Context, resumeToken []byte) (streamingReceiver, error) {
-				return mc.ExecuteStreamingSql(ct, &sppb.ExecuteSqlRequest{
-					Sql:         "SELECT t.key key, t.value value FROM t_mock t",
-					ResumeToken: resumeToken,
-				})
-			},
-			nil,
-			func(error) {})
-		defer iter.Stop()
-		for {
-			_, err = iter.Next()
-			if err == iterator.Done {
-				err = nil
-				break
-			}
-			if err != nil {
-				break
-			}
-		}
-		done <- 0
-	}()
-	select {
-	case <-done:
-		if wantErr := codes.DeadlineExceeded; ErrCode(err) != wantErr {
-			t.Errorf("streaming query timeout returns error %v, want error code %v", err, wantErr)
-		}
-	case <-time.After(2 * time.Second):
-		t.Errorf("query doesn't timeout as expected")
-	}
-}
-
-func TestRowIteratorDo(t *testing.T) {
-	restore := setMaxBytesBetweenResumeTokens()
-	defer restore()
-	ms := testutil.NewMockCloudSpanner(t, trxTs)
-	ms.Serve()
-	defer ms.Stop()
-	cc, err := grpc.Dial(ms.Addr(), grpc.WithInsecure())
-	if err != nil {
-		t.Fatalf("Dial(%q) = %v", ms.Addr(), err)
-	}
-	defer cc.Close()
-	mc := sppb.NewSpannerClient(cc)
-
-	for i := 0; i < 3; i++ {
-		ms.AddMsg(nil, false)
-	}
-	ms.AddMsg(io.EOF, true)
-	nRows := 0
-	iter := stream(context.Background(),
-		func(ct context.Context, resumeToken []byte) (streamingReceiver, error) {
-			return mc.ExecuteStreamingSql(ct, &sppb.ExecuteSqlRequest{
-				Sql:         "SELECT t.key key, t.value value FROM t_mock t",
-				ResumeToken: resumeToken,
-			})
-		},
-		nil,
-		func(error) {})
-	err = iter.Do(func(r *Row) error { nRows++; return nil })
-	if err != nil {
-		t.Errorf("Using Do: %v", err)
-	}
-	if nRows != 3 {
-		t.Errorf("got %d rows, want 3", nRows)
-	}
-}
-
-func TestIteratorStopEarly(t *testing.T) {
-	ctx := context.Background()
-	restore := setMaxBytesBetweenResumeTokens()
-	defer restore()
-	ms := testutil.NewMockCloudSpanner(t, trxTs)
-	ms.Serve()
-	defer ms.Stop()
-	cc, err := grpc.Dial(ms.Addr(), grpc.WithInsecure())
-	if err != nil {
-		t.Fatalf("Dial(%q) = %v", ms.Addr(), err)
-	}
-	defer cc.Close()
-	mc := sppb.NewSpannerClient(cc)
-
-	ms.AddMsg(nil, false)
-	ms.AddMsg(nil, false)
-	ms.AddMsg(io.EOF, true)
-
-	iter := stream(ctx,
-		func(ct context.Context, resumeToken []byte) (streamingReceiver, error) {
-			return mc.ExecuteStreamingSql(ct, &sppb.ExecuteSqlRequest{
-				Sql:         "SELECT t.key key, t.value value FROM t_mock t",
-				ResumeToken: resumeToken,
-			})
-		},
-		nil,
-		func(error) {})
-	_, err = iter.Next()
-	if err != nil {
-		t.Fatalf("before Stop: %v", err)
-	}
-	iter.Stop()
-	// Stop sets r.err to the FailedPrecondition error "Next called after Stop".
-	// Override that here so this test can observe the Canceled error from the stream.
-	iter.err = nil
-	iter.Next()
-	if ErrCode(iter.streamd.lastErr()) != codes.Canceled {
-		t.Errorf("after Stop: got %v, wanted Canceled", err)
-	}
-}
-
-func TestIteratorWithError(t *testing.T) {
-	injected := errors.New("Failed iterator")
-	iter := RowIterator{err: injected}
-	defer iter.Stop()
-	if _, err := iter.Next(); err != injected {
-		t.Fatalf("Expected error: %v, got %v", injected, err)
-	}
-}
diff --git a/vendor/cloud.google.com/go/spanner/retry.go b/vendor/cloud.google.com/go/spanner/retry.go
deleted file mode 100644
index 6d535ef41..000000000
--- a/vendor/cloud.google.com/go/spanner/retry.go
+++ /dev/null
@@ -1,192 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"fmt"
-	"strings"
-	"time"
-
-	"github.com/golang/protobuf/proto"
-	"github.com/golang/protobuf/ptypes"
-	"golang.org/x/net/context"
-	edpb "google.golang.org/genproto/googleapis/rpc/errdetails"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/metadata"
-)
-
-const (
-	retryInfoKey = "google.rpc.retryinfo-bin"
-)
-
-// errRetry returns an unavailable error under error namespace EsOther. It is a
-// generic retryable error that is used to mask and recover unretryable errors
-// in a retry loop.
-func errRetry(err error) error {
-	if se, ok := err.(*Error); ok {
-		return &Error{codes.Unavailable, fmt.Sprintf("generic Cloud Spanner retryable error: { %v }", se.Error()), se.trailers}
-	}
-	return spannerErrorf(codes.Unavailable, "generic Cloud Spanner retryable error: { %v }", err.Error())
-}
-
-// isErrorClosing reports whether the error is generated by gRPC layer talking to a closed server.
-func isErrorClosing(err error) bool {
-	if err == nil {
-		return false
-	}
-	if ErrCode(err) == codes.Internal && strings.Contains(ErrDesc(err), "transport is closing") {
-		// Handle the case when connection is closed unexpectedly.
-		// TODO: once gRPC is able to categorize
-		// this as retryable error, we should stop parsing the
-		// error message here.
-		return true
-	}
-	return false
-}
-
-// isErrorRST reports whether the error is generated by gRPC client receiving a RST frame from server.
-func isErrorRST(err error) bool {
-	if err == nil {
-		return false
-	}
-	if ErrCode(err) == codes.Internal && strings.Contains(ErrDesc(err), "stream terminated by RST_STREAM") {
-		// TODO: once gRPC is able to categorize this error as "go away" or "retryable",
-		// we should stop parsing the error message.
-		return true
-	}
-	return false
-}
-
-// isErrorUnexpectedEOF returns true if error is generated by gRPC layer
-// receiving io.EOF unexpectedly.
-func isErrorUnexpectedEOF(err error) bool {
-	if err == nil {
-		return false
-	}
-	if ErrCode(err) == codes.Unknown && strings.Contains(ErrDesc(err), "unexpected EOF") {
-		// Unexpected EOF is an transport layer issue that
-		// could be recovered by retries. The most likely
-		// scenario is a flaky RecvMsg() call due to network
-		// issues.
-		// TODO: once gRPC is able to categorize
-		// this as retryable error, we should stop parsing the
-		// error message here.
-		return true
-	}
-	return false
-}
-
-// isErrorUnavailable returns true if the error is about server being unavailable.
-func isErrorUnavailable(err error) bool {
-	if err == nil {
-		return false
-	}
-	if ErrCode(err) == codes.Unavailable {
-		return true
-	}
-	return false
-}
-
-// isRetryable returns true if the Cloud Spanner error being checked is a retryable error.
-func isRetryable(err error) bool {
-	if isErrorClosing(err) {
-		return true
-	}
-	if isErrorUnexpectedEOF(err) {
-		return true
-	}
-	if isErrorRST(err) {
-		return true
-	}
-	if isErrorUnavailable(err) {
-		return true
-	}
-	return false
-}
-
-// errContextCanceled returns *spanner.Error for canceled context.
-func errContextCanceled(ctx context.Context, lastErr error) error {
-	if ctx.Err() == context.DeadlineExceeded {
-		return spannerErrorf(codes.DeadlineExceeded, "%v, lastErr is <%v>", ctx.Err(), lastErr)
-	}
-	return spannerErrorf(codes.Canceled, "%v, lastErr is <%v>", ctx.Err(), lastErr)
-}
-
-// extractRetryDelay extracts retry backoff if present.
-func extractRetryDelay(err error) (time.Duration, bool) {
-	trailers := errTrailers(err)
-	if trailers == nil {
-		return 0, false
-	}
-	elem, ok := trailers[retryInfoKey]
-	if !ok || len(elem) <= 0 {
-		return 0, false
-	}
-	_, b, err := metadata.DecodeKeyValue(retryInfoKey, elem[0])
-	if err != nil {
-		return 0, false
-	}
-	var retryInfo edpb.RetryInfo
-	if proto.Unmarshal([]byte(b), &retryInfo) != nil {
-		return 0, false
-	}
-	delay, err := ptypes.Duration(retryInfo.RetryDelay)
-	if err != nil {
-		return 0, false
-	}
-	return delay, true
-}
-
-// runRetryable keeps attempting to run f until one of the following happens:
-//     1) f returns nil error or an unretryable error;
-//     2) context is cancelled or timeout.
-// TODO: consider using https://github.com/googleapis/gax-go once it
-// becomes available internally.
-func runRetryable(ctx context.Context, f func(context.Context) error) error {
-	var funcErr error
-	retryCount := 0
-	for {
-		select {
-		case <-ctx.Done():
-			// Do context check here so that even f() failed to do
-			// so (for example, gRPC implementation bug), the loop
-			// can still have a chance to exit as expected.
-			return errContextCanceled(ctx, funcErr)
-		default:
-		}
-		funcErr = f(ctx)
-		if funcErr == nil {
-			return nil
-		}
-		if isRetryable(funcErr) {
-			// Error is retryable, do exponential backoff and continue.
-			b, ok := extractRetryDelay(funcErr)
-			if !ok {
-				b = defaultBackoff.delay(retryCount)
-			}
-			select {
-			case <-ctx.Done():
-				return errContextCanceled(ctx, funcErr)
-			case <-time.After(b):
-			}
-			retryCount++
-			continue
-		}
-		// Error isn't retryable / no error, return immediately.
-		return toSpannerError(funcErr)
-	}
-}
diff --git a/vendor/cloud.google.com/go/spanner/retry_test.go b/vendor/cloud.google.com/go/spanner/retry_test.go
deleted file mode 100644
index 49c5051ab..000000000
--- a/vendor/cloud.google.com/go/spanner/retry_test.go
+++ /dev/null
@@ -1,108 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"errors"
-	"fmt"
-	"reflect"
-	"testing"
-	"time"
-
-	"github.com/golang/protobuf/proto"
-	"github.com/golang/protobuf/ptypes"
-	"golang.org/x/net/context"
-	edpb "google.golang.org/genproto/googleapis/rpc/errdetails"
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/metadata"
-)
-
-// Test if runRetryable loop deals with various errors correctly.
-func TestRetry(t *testing.T) {
-	if testing.Short() {
-		t.SkipNow()
-	}
-	responses := []error{
-		grpc.Errorf(codes.Internal, "transport is closing"),
-		grpc.Errorf(codes.Unknown, "unexpected EOF"),
-		grpc.Errorf(codes.Internal, "stream terminated by RST_STREAM with error code: 2"),
-		grpc.Errorf(codes.Unavailable, "service is currently unavailable"),
-		errRetry(fmt.Errorf("just retry it")),
-	}
-	err := runRetryable(context.Background(), func(ct context.Context) error {
-		var r error
-		if len(responses) > 0 {
-			r = responses[0]
-			responses = responses[1:]
-		}
-		return r
-	})
-	if err != nil {
-		t.Errorf("runRetryable should be able to survive all retryable errors, but it returns %v", err)
-	}
-	// Unretryable errors
-	injErr := errors.New("this is unretryable")
-	err = runRetryable(context.Background(), func(ct context.Context) error {
-		return injErr
-	})
-	if wantErr := toSpannerError(injErr); !reflect.DeepEqual(err, wantErr) {
-		t.Errorf("runRetryable returns error %v, want %v", err, wantErr)
-	}
-	// Timeout
-	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
-	defer cancel()
-	retryErr := errRetry(fmt.Errorf("still retrying"))
-	err = runRetryable(ctx, func(ct context.Context) error {
-		// Expect to trigger timeout in retryable runner after 10 executions.
-		<-time.After(100 * time.Millisecond)
-		// Let retryable runner to retry so that timeout will eventually happen.
-		return retryErr
-	})
-	// Check error code and error message
-	if wantErrCode, wantErr := codes.DeadlineExceeded, errContextCanceled(ctx, retryErr); ErrCode(err) != wantErrCode || !reflect.DeepEqual(err, wantErr) {
-		t.Errorf("<err code, err>=\n<%v, %v>, want:\n<%v, %v>", ErrCode(err), err, wantErrCode, wantErr)
-	}
-	// Cancellation
-	ctx, cancel = context.WithCancel(context.Background())
-	retries := 3
-	retryErr = errRetry(fmt.Errorf("retry before cancel"))
-	err = runRetryable(ctx, func(ct context.Context) error {
-		retries--
-		if retries == 0 {
-			cancel()
-		}
-		return retryErr
-	})
-	// Check error code, error message, retry count
-	if wantErrCode, wantErr := codes.Canceled, errContextCanceled(ctx, retryErr); ErrCode(err) != wantErrCode || !reflect.DeepEqual(err, wantErr) || retries != 0 {
-		t.Errorf("<err code, err, retries>=\n<%v, %v, %v>, want:\n<%v, %v, %v>", ErrCode(err), err, retries, wantErrCode, wantErr, 0)
-	}
-}
-
-func TestRetryInfo(t *testing.T) {
-	b, _ := proto.Marshal(&edpb.RetryInfo{
-		RetryDelay: ptypes.DurationProto(time.Second),
-	})
-	trailers := map[string]string{
-		retryInfoKey: string(b),
-	}
-	gotDelay, ok := extractRetryDelay(errRetry(toSpannerErrorWithMetadata(grpc.Errorf(codes.Aborted, ""), metadata.New(trailers))))
-	if !ok || !reflect.DeepEqual(time.Second, gotDelay) {
-		t.Errorf("<ok, retryDelay> = <%t, %v>, want <true, %v>", ok, gotDelay, time.Second)
-	}
-}
diff --git a/vendor/cloud.google.com/go/spanner/row.go b/vendor/cloud.google.com/go/spanner/row.go
deleted file mode 100644
index e8f30103d..000000000
--- a/vendor/cloud.google.com/go/spanner/row.go
+++ /dev/null
@@ -1,308 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"fmt"
-	"reflect"
-
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-	"google.golang.org/grpc/codes"
-)
-
-// A Row is a view of a row of data produced by a Cloud Spanner read.
-//
-// A row consists of a number of columns; the number depends on the columns
-// used to construct the read.
-//
-// The column values can be accessed by index, where the indices are with
-// respect to the columns. For instance, if the read specified
-// []string{"photo_id", "caption", "metadata"}, then each row will
-// contain three columns: the 0th column corresponds to "photo_id", the
-// 1st column corresponds to "caption", etc.
-//
-// Column values are decoded by using one of the Column, ColumnByName, or
-// Columns methods. The valid values passed to these methods depend on the
-// column type. For example:
-//
-//	var photoID int64
-//	err := row.Column(0, &photoID) // Decode column 0 as an integer.
-//
-//	var caption string
-//	err := row.Column(1, &caption) // Decode column 1 as a string.
-//
-//	// The above two operations at once.
-//	err := row.Columns(&photoID, &caption)
-//
-// Supported types and their corresponding Cloud Spanner column type(s) are:
-//
-//	*string(not NULL), *NullString - STRING
-//	*[]NullString - STRING ARRAY
-//	*[]byte - BYTES
-//	*[][]byte - BYTES ARRAY
-//	*int64(not NULL), *NullInt64 - INT64
-//	*[]NullInt64 - INT64 ARRAY
-//	*bool(not NULL), *NullBool - BOOL
-//	*[]NullBool - BOOL ARRAY
-//	*float64(not NULL), *NullFloat64 - FLOAT64
-//	*[]NullFloat64 - FLOAT64 ARRAY
-//	*time.Time(not NULL), *NullTime - TIMESTAMP
-//	*[]NullTime - TIMESTAMP ARRAY
-//	*Date(not NULL), *NullDate - DATE
-//	*[]NullDate - DATE ARRAY
-//	*[]*some_go_struct, *[]NullRow - STRUCT ARRAY
-//	*GenericColumnValue - any Cloud Spanner type
-//
-// For TIMESTAMP columns, returned time.Time object will be in UTC.
-//
-// To fetch an array of BYTES, pass a *[][]byte. To fetch an array of
-// (sub)rows, pass a *[]spanner.NullRow or a *[]*some_go_struct where
-// some_go_struct holds all information of the subrow, see spannr.Row.ToStruct
-// for the mapping between Cloud Spanner row and Go struct. To fetch an array of
-// other types, pass a *[]spanner.Null* type of the appropriate type.  Use
-// *GenericColumnValue when you don't know in advance what column type to
-// expect.
-//
-// Row decodes the row contents lazily; as a result, each call to a getter has
-// a chance of returning an error.
-//
-// A column value may be NULL if the corresponding value is not present in
-// Cloud Spanner. The spanner.Null* types (spanner.NullInt64 et al.) allow fetching
-// values that may be null. A NULL BYTES can be fetched into a *[]byte as nil.
-// It is an error to fetch a NULL value into any other type.
-type Row struct {
-	fields []*sppb.StructType_Field
-	vals   []*proto3.Value // keep decoded for now
-}
-
-// errNamesValuesMismatch returns error for when columnNames count is not equal
-// to columnValues count.
-func errNamesValuesMismatch(columnNames []string, columnValues []interface{}) error {
-	return spannerErrorf(codes.FailedPrecondition,
-		"different number of names(%v) and values(%v)", len(columnNames), len(columnValues))
-}
-
-// NewRow returns a Row containing the supplied data.  This can be useful for
-// mocking Cloud Spanner Read and Query responses for unit testing.
-func NewRow(columnNames []string, columnValues []interface{}) (*Row, error) {
-	if len(columnValues) != len(columnNames) {
-		return nil, errNamesValuesMismatch(columnNames, columnValues)
-	}
-	r := Row{
-		fields: make([]*sppb.StructType_Field, len(columnValues)),
-		vals:   make([]*proto3.Value, len(columnValues)),
-	}
-	for i := range columnValues {
-		val, typ, err := encodeValue(columnValues[i])
-		if err != nil {
-			return nil, err
-		}
-		r.fields[i] = &sppb.StructType_Field{
-			Name: columnNames[i],
-			Type: typ,
-		}
-		r.vals[i] = val
-	}
-	return &r, nil
-}
-
-// Size is the number of columns in the row.
-func (r *Row) Size() int {
-	return len(r.fields)
-}
-
-// ColumnName returns the name of column i, or empty string for invalid column.
-func (r *Row) ColumnName(i int) string {
-	if i < 0 || i >= len(r.fields) {
-		return ""
-	}
-	return r.fields[i].Name
-}
-
-// ColumnIndex returns the index of the column with the given name. The
-// comparison is case-sensitive.
-func (r *Row) ColumnIndex(name string) (int, error) {
-	found := false
-	var index int
-	if len(r.vals) != len(r.fields) {
-		return 0, errFieldsMismatchVals(r)
-	}
-	for i, f := range r.fields {
-		if f == nil {
-			return 0, errNilColType(i)
-		}
-		if name == f.Name {
-			if found {
-				return 0, errDupColName(name)
-			}
-			found = true
-			index = i
-		}
-	}
-	if !found {
-		return 0, errColNotFound(name)
-	}
-	return index, nil
-}
-
-// ColumnNames returns all column names of the row.
-func (r *Row) ColumnNames() []string {
-	var n []string
-	for _, c := range r.fields {
-		n = append(n, c.Name)
-	}
-	return n
-}
-
-// errColIdxOutOfRange returns error for requested column index is out of the
-// range of the target Row's columns.
-func errColIdxOutOfRange(i int, r *Row) error {
-	return spannerErrorf(codes.OutOfRange, "column index %d out of range [0,%d)", i, len(r.vals))
-}
-
-// errDecodeColumn returns error for not being able to decode a indexed column.
-func errDecodeColumn(i int, err error) error {
-	if err == nil {
-		return nil
-	}
-	se, ok := toSpannerError(err).(*Error)
-	if !ok {
-		return spannerErrorf(codes.InvalidArgument, "failed to decode column %v, error = <%v>", i, err)
-	}
-	se.decorate(fmt.Sprintf("failed to decode column %v", i))
-	return se
-}
-
-// errFieldsMismatchVals returns error for field count isn't equal to value count in a Row.
-func errFieldsMismatchVals(r *Row) error {
-	return spannerErrorf(codes.FailedPrecondition, "row has different number of fields(%v) and values(%v)",
-		len(r.fields), len(r.vals))
-}
-
-// errNilColType returns error for column type for column i being nil in the row.
-func errNilColType(i int) error {
-	return spannerErrorf(codes.FailedPrecondition, "column(%v)'s type is nil", i)
-}
-
-// Column fetches the value from the ith column, decoding it into ptr.
-// See the Row documentation for the list of acceptable argument types.
-// see Client.ReadWriteTransaction for an example.
-func (r *Row) Column(i int, ptr interface{}) error {
-	if len(r.vals) != len(r.fields) {
-		return errFieldsMismatchVals(r)
-	}
-	if i < 0 || i >= len(r.fields) {
-		return errColIdxOutOfRange(i, r)
-	}
-	if r.fields[i] == nil {
-		return errNilColType(i)
-	}
-	if err := decodeValue(r.vals[i], r.fields[i].Type, ptr); err != nil {
-		return errDecodeColumn(i, err)
-	}
-	return nil
-}
-
-// errDupColName returns error for duplicated column name in the same row.
-func errDupColName(n string) error {
-	return spannerErrorf(codes.FailedPrecondition, "ambiguous column name %q", n)
-}
-
-// errColNotFound returns error for not being able to find a named column.
-func errColNotFound(n string) error {
-	return spannerErrorf(codes.NotFound, "column %q not found", n)
-}
-
-// ColumnByName fetches the value from the named column, decoding it into ptr.
-// See the Row documentation for the list of acceptable argument types.
-func (r *Row) ColumnByName(name string, ptr interface{}) error {
-	index, err := r.ColumnIndex(name)
-	if err != nil {
-		return err
-	}
-	return r.Column(index, ptr)
-}
-
-// errNumOfColValue returns error for providing wrong number of values to Columns.
-func errNumOfColValue(n int, r *Row) error {
-	return spannerErrorf(codes.InvalidArgument,
-		"Columns(): number of arguments (%d) does not match row size (%d)", n, len(r.vals))
-}
-
-// Columns fetches all the columns in the row at once.
-//
-// The value of the kth column will be decoded into the kth argument to
-// Columns.  See above for the list of acceptable argument types. The number of
-// arguments must be equal to the number of columns. Pass nil to specify that a
-// column should be ignored.
-func (r *Row) Columns(ptrs ...interface{}) error {
-	if len(ptrs) != len(r.vals) {
-		return errNumOfColValue(len(ptrs), r)
-	}
-	if len(r.vals) != len(r.fields) {
-		return errFieldsMismatchVals(r)
-	}
-	for i, p := range ptrs {
-		if p == nil {
-			continue
-		}
-		if err := r.Column(i, p); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-// errToStructArgType returns error for p not having the correct data type(pointer to Go struct) to
-// be the argument of Row.ToStruct.
-func errToStructArgType(p interface{}) error {
-	return spannerErrorf(codes.InvalidArgument, "ToStruct(): type %T is not a valid pointer to Go struct", p)
-}
-
-// ToStruct fetches the columns in a row into the fields of a struct.
-// The rules for mapping a row's columns into a struct's exported fields
-// are as the following:
-//   1. If a field has a `spanner: "column_name"` tag, then decode column
-//      'column_name' into the field. A special case is the `spanner: "-"`
-//      tag, which instructs ToStruct to ignore the field during decoding.
-//   2. Otherwise, if the name of a field matches the name of a column (ignoring case),
-//      decode the column into the field.
-//
-// The fields of the destination struct can be of any type that is acceptable
-// to (*spanner.Row).Column.
-//
-// Slice and pointer fields will be set to nil if the source column
-// is NULL, and a non-nil value if the column is not NULL. To decode NULL
-// values of other types, use one of the spanner.Null* as the type of the
-// destination field.
-func (r *Row) ToStruct(p interface{}) error {
-	// Check if p is a pointer to a struct
-	if t := reflect.TypeOf(p); t == nil || t.Kind() != reflect.Ptr || t.Elem().Kind() != reflect.Struct {
-		return errToStructArgType(p)
-	}
-	if len(r.vals) != len(r.fields) {
-		return errFieldsMismatchVals(r)
-	}
-	// Call decodeStruct directly to decode the row as a typed proto.ListValue.
-	return decodeStruct(
-		&sppb.StructType{Fields: r.fields},
-		&proto3.ListValue{Values: r.vals},
-		p,
-	)
-}
diff --git a/vendor/cloud.google.com/go/spanner/row_test.go b/vendor/cloud.google.com/go/spanner/row_test.go
deleted file mode 100644
index 2120421ac..000000000
--- a/vendor/cloud.google.com/go/spanner/row_test.go
+++ /dev/null
@@ -1,1775 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"encoding/base64"
-	"reflect"
-	"strconv"
-	"strings"
-	"testing"
-	"time"
-
-	"cloud.google.com/go/civil"
-	proto "github.com/golang/protobuf/proto"
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-)
-
-var (
-	tm    = time.Date(2016, 11, 15, 0, 0, 0, 0, time.UTC)
-	dt, _ = civil.ParseDate("2016-11-15")
-	// row contains a column for each unique Cloud Spanner type.
-	row = Row{
-		[]*sppb.StructType_Field{
-			// STRING / STRING ARRAY
-			{"STRING", stringType()},
-			{"NULL_STRING", stringType()},
-			{"STRING_ARRAY", listType(stringType())},
-			{"NULL_STRING_ARRAY", listType(stringType())},
-			// BYTES / BYTES ARRAY
-			{"BYTES", bytesType()},
-			{"NULL_BYTES", bytesType()},
-			{"BYTES_ARRAY", listType(bytesType())},
-			{"NULL_BYTES_ARRAY", listType(bytesType())},
-			// INT64 / INT64 ARRAY
-			{"INT64", intType()},
-			{"NULL_INT64", intType()},
-			{"INT64_ARRAY", listType(intType())},
-			{"NULL_INT64_ARRAY", listType(intType())},
-			// BOOL / BOOL ARRAY
-			{"BOOL", boolType()},
-			{"NULL_BOOL", boolType()},
-			{"BOOL_ARRAY", listType(boolType())},
-			{"NULL_BOOL_ARRAY", listType(boolType())},
-			// FLOAT64 / FLOAT64 ARRAY
-			{"FLOAT64", floatType()},
-			{"NULL_FLOAT64", floatType()},
-			{"FLOAT64_ARRAY", listType(floatType())},
-			{"NULL_FLOAT64_ARRAY", listType(floatType())},
-			// TIMESTAMP / TIMESTAMP ARRAY
-			{"TIMESTAMP", timeType()},
-			{"NULL_TIMESTAMP", timeType()},
-			{"TIMESTAMP_ARRAY", listType(timeType())},
-			{"NULL_TIMESTAMP_ARRAY", listType(timeType())},
-			// DATE / DATE ARRAY
-			{"DATE", dateType()},
-			{"NULL_DATE", dateType()},
-			{"DATE_ARRAY", listType(dateType())},
-			{"NULL_DATE_ARRAY", listType(dateType())},
-
-			// STRUCT ARRAY
-			{
-				"STRUCT_ARRAY",
-				listType(
-					structType(
-						mkField("Col1", intType()),
-						mkField("Col2", floatType()),
-						mkField("Col3", stringType()),
-					),
-				),
-			},
-			{
-				"NULL_STRUCT_ARRAY",
-				listType(
-					structType(
-						mkField("Col1", intType()),
-						mkField("Col2", floatType()),
-						mkField("Col3", stringType()),
-					),
-				),
-			},
-		},
-		[]*proto3.Value{
-			// STRING / STRING ARRAY
-			stringProto("value"),
-			nullProto(),
-			listProto(stringProto("value1"), nullProto(), stringProto("value3")),
-			nullProto(),
-			// BYTES / BYTES ARRAY
-			bytesProto([]byte("value")),
-			nullProto(),
-			listProto(bytesProto([]byte("value1")), nullProto(), bytesProto([]byte("value3"))),
-			nullProto(),
-			// INT64 / INT64 ARRAY
-			intProto(17),
-			nullProto(),
-			listProto(intProto(1), intProto(2), nullProto()),
-			nullProto(),
-			// BOOL / BOOL ARRAY
-			boolProto(true),
-			nullProto(),
-			listProto(nullProto(), boolProto(true), boolProto(false)),
-			nullProto(),
-			// FLOAT64 / FLOAT64 ARRAY
-			floatProto(1.7),
-			nullProto(),
-			listProto(nullProto(), nullProto(), floatProto(1.7)),
-			nullProto(),
-			// TIMESTAMP / TIMESTAMP ARRAY
-			timeProto(tm),
-			nullProto(),
-			listProto(nullProto(), timeProto(tm)),
-			nullProto(),
-			// DATE / DATE ARRAY
-			dateProto(dt),
-			nullProto(),
-			listProto(nullProto(), dateProto(dt)),
-			nullProto(),
-			// STRUCT ARRAY
-			listProto(
-				nullProto(),
-				listProto(intProto(3), floatProto(33.3), stringProto("three")),
-				nullProto(),
-			),
-			nullProto(),
-		},
-	}
-)
-
-// Test helpers for getting column values.
-func TestColumnValues(t *testing.T) {
-	vals := []interface{}{}
-	wantVals := []interface{}{}
-	// Test getting column values.
-	for i, wants := range [][]interface{}{
-		// STRING / STRING ARRAY
-		{"value", NullString{"value", true}},
-		{NullString{}},
-		{[]NullString{{"value1", true}, {}, {"value3", true}}},
-		{[]NullString(nil)},
-		// BYTES / BYTES ARRAY
-		{[]byte("value")},
-		{[]byte(nil)},
-		{[][]byte{[]byte("value1"), nil, []byte("value3")}},
-		{[][]byte(nil)},
-		// INT64 / INT64 ARRAY
-		{int64(17), NullInt64{17, true}},
-		{NullInt64{}},
-		{[]NullInt64{{1, true}, {2, true}, {}}},
-		{[]NullInt64(nil)},
-		// BOOL / BOOL ARRAY
-		{true, NullBool{true, true}},
-		{NullBool{}},
-		{[]NullBool{{}, {true, true}, {false, true}}},
-		{[]NullBool(nil)},
-		// FLOAT64 / FLOAT64 ARRAY
-		{1.7, NullFloat64{1.7, true}},
-		{NullFloat64{}},
-		{[]NullFloat64{{}, {}, {1.7, true}}},
-		{[]NullFloat64(nil)},
-		// TIMESTAMP / TIMESTAMP ARRAY
-		{tm, NullTime{tm, true}},
-		{NullTime{}},
-		{[]NullTime{{}, {tm, true}}},
-		{[]NullTime(nil)},
-		// DATE / DATE ARRAY
-		{dt, NullDate{dt, true}},
-		{NullDate{}},
-		{[]NullDate{{}, {dt, true}}},
-		{[]NullDate(nil)},
-		// STRUCT ARRAY
-		{
-			[]*struct {
-				Col1 NullInt64
-				Col2 NullFloat64
-				Col3 string
-			}{
-				nil,
-				&struct {
-					Col1 NullInt64
-					Col2 NullFloat64
-					Col3 string
-				}{
-					NullInt64{3, true},
-					NullFloat64{33.3, true},
-					"three",
-				},
-				nil,
-			},
-			[]NullRow{
-				{},
-				{
-					Row: Row{
-						fields: []*sppb.StructType_Field{
-							mkField("Col1", intType()),
-							mkField("Col2", floatType()),
-							mkField("Col3", stringType()),
-						},
-						vals: []*proto3.Value{
-							intProto(3),
-							floatProto(33.3),
-							stringProto("three"),
-						},
-					},
-					Valid: true,
-				},
-				{},
-			},
-		},
-		{
-			[]*struct {
-				Col1 NullInt64
-				Col2 NullFloat64
-				Col3 string
-			}(nil),
-			[]NullRow(nil),
-		},
-	} {
-		for j, want := range wants {
-			// Prepare Value vector to test Row.Columns.
-			if j == 0 {
-				vals = append(vals, reflect.New(reflect.TypeOf(want)).Interface())
-				wantVals = append(wantVals, want)
-			}
-			// Column
-			gotp := reflect.New(reflect.TypeOf(want))
-			err := row.Column(i, gotp.Interface())
-			if err != nil {
-				t.Errorf("\t row.Column(%v, %T) returns error: %v, want nil", i, gotp.Interface(), err)
-			}
-			if got := reflect.Indirect(gotp).Interface(); !reflect.DeepEqual(got, want) {
-				t.Errorf("\t row.Column(%v, %T) retrives %v, want %v", i, gotp.Interface(), got, want)
-			}
-			// ColumnByName
-			gotp = reflect.New(reflect.TypeOf(want))
-			err = row.ColumnByName(row.fields[i].Name, gotp.Interface())
-			if err != nil {
-				t.Errorf("\t row.ColumnByName(%v, %T) returns error: %v, want nil", row.fields[i].Name, gotp.Interface(), err)
-			}
-			if got := reflect.Indirect(gotp).Interface(); !reflect.DeepEqual(got, want) {
-				t.Errorf("\t row.ColumnByName(%v, %T) retrives %v, want %v", row.fields[i].Name, gotp.Interface(), got, want)
-			}
-		}
-	}
-	// Test Row.Columns.
-	if err := row.Columns(vals...); err != nil {
-		t.Errorf("row.Columns() returns error: %v, want nil", err)
-	}
-	for i, want := range wantVals {
-		if got := reflect.Indirect(reflect.ValueOf(vals[i])).Interface(); !reflect.DeepEqual(got, want) {
-			t.Errorf("\t got %v(%T) for column[%v], want %v(%T)", got, got, row.fields[i].Name, want, want)
-		}
-	}
-}
-
-// Test decoding into nil destination.
-func TestNilDst(t *testing.T) {
-	for i, test := range []struct {
-		r               *Row
-		dst             interface{}
-		wantErr         error
-		structDst       interface{}
-		wantToStructErr error
-	}{
-		{
-			&Row{
-				[]*sppb.StructType_Field{
-					{"Col0", stringType()},
-				},
-				[]*proto3.Value{stringProto("value")},
-			},
-			nil,
-			errDecodeColumn(0, errNilDst(nil)),
-			nil,
-			errToStructArgType(nil),
-		},
-		{
-			&Row{
-				[]*sppb.StructType_Field{
-					{"Col0", stringType()},
-				},
-				[]*proto3.Value{stringProto("value")},
-			},
-			(*string)(nil),
-			errDecodeColumn(0, errNilDst((*string)(nil))),
-			(*struct{ STRING string })(nil),
-			errNilDst((*struct{ STRING string })(nil)),
-		},
-		{
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(
-							structType(
-								mkField("Col1", intType()),
-								mkField("Col2", floatType()),
-							),
-						),
-					},
-				},
-				[]*proto3.Value{listProto(
-					listProto(intProto(3), floatProto(33.3)),
-				)},
-			},
-			(*[]*struct {
-				Col1 int
-				Col2 float64
-			})(nil),
-			errDecodeColumn(0, errNilDst((*[]*struct {
-				Col1 int
-				Col2 float64
-			})(nil))),
-			(*struct {
-				StructArray []*struct {
-					Col1 int
-					Col2 float64
-				} `spanner:"STRUCT_ARRAY"`
-			})(nil),
-			errNilDst((*struct {
-				StructArray []*struct {
-					Col1 int
-					Col2 float64
-				} `spanner:"STRUCT_ARRAY"`
-			})(nil)),
-		},
-	} {
-		if gotErr := test.r.Column(0, test.dst); !reflect.DeepEqual(gotErr, test.wantErr) {
-			t.Errorf("%v: test.r.Column() returns error %v, want %v", i, gotErr, test.wantErr)
-		}
-		if gotErr := test.r.ColumnByName("Col0", test.dst); !reflect.DeepEqual(gotErr, test.wantErr) {
-			t.Errorf("%v: test.r.ColumnByName() returns error %v, want %v", i, gotErr, test.wantErr)
-		}
-		// Row.Columns(T) should return nil on T == nil, otherwise, it should return test.wantErr.
-		wantColumnsErr := test.wantErr
-		if test.dst == nil {
-			wantColumnsErr = nil
-		}
-		if gotErr := test.r.Columns(test.dst); !reflect.DeepEqual(gotErr, wantColumnsErr) {
-			t.Errorf("%v: test.r.Columns() returns error %v, want %v", i, gotErr, wantColumnsErr)
-		}
-		if gotErr := test.r.ToStruct(test.structDst); !reflect.DeepEqual(gotErr, test.wantToStructErr) {
-			t.Errorf("%v: test.r.ToStruct() returns error %v, want %v", i, gotErr, test.wantToStructErr)
-		}
-	}
-}
-
-// Test decoding NULL columns using Go types that don't support NULL.
-func TestNullTypeErr(t *testing.T) {
-	var tm time.Time
-	ntoi := func(n string) int {
-		for i, f := range row.fields {
-			if f.Name == n {
-				return i
-			}
-		}
-		t.Errorf("cannot find column name %q in row", n)
-		return 0
-	}
-	for _, test := range []struct {
-		colName string
-		dst     interface{}
-	}{
-		{
-			"NULL_STRING",
-			proto.String(""),
-		},
-		{
-			"NULL_INT64",
-			proto.Int64(0),
-		},
-		{
-			"NULL_BOOL",
-			proto.Bool(false),
-		},
-		{
-			"NULL_FLOAT64",
-			proto.Float64(0.0),
-		},
-		{
-			"NULL_TIMESTAMP",
-			&tm,
-		},
-		{
-			"NULL_DATE",
-			&dt,
-		},
-	} {
-		wantErr := errDecodeColumn(ntoi(test.colName), errDstNotForNull(test.dst))
-		if gotErr := row.ColumnByName(test.colName, test.dst); !reflect.DeepEqual(gotErr, wantErr) {
-			t.Errorf("row.ColumnByName(%v) returns error %v, want %v", test.colName, gotErr, wantErr)
-		}
-	}
-}
-
-// Test using wrong destination type in column decoders.
-func TestColumnTypeErr(t *testing.T) {
-	// badDst cannot hold any of the column values.
-	badDst := &struct{}{}
-	for i, f := range row.fields { // For each of the columns, try to decode it into badDst.
-		tc := f.Type.Code
-		isArray := strings.Contains(f.Name, "ARRAY")
-		if isArray {
-			tc = f.Type.ArrayElementType.Code
-		}
-		wantErr := errDecodeColumn(i, errTypeMismatch(tc, isArray, badDst))
-		if gotErr := row.Column(i, badDst); !reflect.DeepEqual(gotErr, wantErr) {
-			t.Errorf("Column(%v): decoding into destination with wrong type %T returns error %v, want %v",
-				i, badDst, gotErr, wantErr)
-		}
-		if gotErr := row.ColumnByName(f.Name, badDst); !reflect.DeepEqual(gotErr, wantErr) {
-			t.Errorf("ColumnByName(%v): decoding into destination with wrong type %T returns error %v, want %v",
-				f.Name, badDst, gotErr, wantErr)
-		}
-	}
-	wantErr := errDecodeColumn(1, errTypeMismatch(sppb.TypeCode_STRING, false, badDst))
-	// badDst is used to receive column 1.
-	vals := []interface{}{nil, badDst} // Row.Column() is expected to fail at column 1.
-	// Skip decoding the rest columns by providing nils as the destinations.
-	for i := 2; i < len(row.fields); i++ {
-		vals = append(vals, nil)
-	}
-	if gotErr := row.Columns(vals...); !reflect.DeepEqual(gotErr, wantErr) {
-		t.Errorf("Columns(): decoding column 1 with wrong type %T returns error %v, want %v",
-			badDst, gotErr, wantErr)
-	}
-}
-
-// Test the handling of invalid column decoding requests which cannot be mapped to correct column(s).
-func TestInvalidColumnRequest(t *testing.T) {
-	for _, test := range []struct {
-		desc    string
-		f       func() error
-		wantErr error
-	}{
-		{
-			"Request column index is out of range",
-			func() error {
-				return row.Column(10000, &struct{}{})
-			},
-			errColIdxOutOfRange(10000, &row),
-		},
-		{
-			"Cannot find the named column",
-			func() error {
-				return row.ColumnByName("string", &struct{}{})
-			},
-			errColNotFound("string"),
-		},
-		{
-			"Not enough arguments to call row.Columns()",
-			func() error {
-				return row.Columns(nil, nil)
-			},
-			errNumOfColValue(2, &row),
-		},
-		{
-			"Call ColumnByName on row with duplicated column names",
-			func() error {
-				var s string
-				r := &Row{
-					[]*sppb.StructType_Field{
-						{"Val", stringType()},
-						{"Val", stringType()},
-					},
-					[]*proto3.Value{stringProto("value1"), stringProto("value2")},
-				}
-				return r.ColumnByName("Val", &s)
-			},
-			errDupColName("Val"),
-		},
-		{
-			"Call ToStruct on row with duplicated column names",
-			func() error {
-				s := &struct {
-					Val string
-				}{}
-				r := &Row{
-					[]*sppb.StructType_Field{
-						{"Val", stringType()},
-						{"Val", stringType()},
-					},
-					[]*proto3.Value{stringProto("value1"), stringProto("value2")},
-				}
-				return r.ToStruct(s)
-			},
-			errDupSpannerField("Val", &sppb.StructType{
-				Fields: []*sppb.StructType_Field{
-					{"Val", stringType()},
-					{"Val", stringType()},
-				},
-			}),
-		},
-		{
-			"Call ToStruct on a row with unnamed field",
-			func() error {
-				s := &struct {
-					Val string
-				}{}
-				r := &Row{
-					[]*sppb.StructType_Field{
-						{"", stringType()},
-					},
-					[]*proto3.Value{stringProto("value1")},
-				}
-				return r.ToStruct(s)
-			},
-			errUnnamedField(&sppb.StructType{Fields: []*sppb.StructType_Field{{"", stringType()}}}, 0),
-		},
-	} {
-		if gotErr := test.f(); !reflect.DeepEqual(gotErr, test.wantErr) {
-			t.Errorf("%v: test.f() returns error %v, want %v", test.desc, gotErr, test.wantErr)
-		}
-	}
-}
-
-// Test decoding the row with row.ToStruct into an invalid destination.
-func TestToStructInvalidDst(t *testing.T) {
-	for _, test := range []struct {
-		desc    string
-		dst     interface{}
-		wantErr error
-	}{
-		{
-			"Decode row as STRUCT into int32",
-			proto.Int(1),
-			errToStructArgType(proto.Int(1)),
-		},
-		{
-			"Decode row as STRUCT to nil Go struct",
-			(*struct{})(nil),
-			errNilDst((*struct{})(nil)),
-		},
-		{
-			"Decode row as STRUCT to Go struct with duplicated fields for the PK column",
-			&struct {
-				PK1 string `spanner:"STRING"`
-				PK2 string `spanner:"STRING"`
-			}{},
-			errNoOrDupGoField(&struct {
-				PK1 string `spanner:"STRING"`
-				PK2 string `spanner:"STRING"`
-			}{}, "STRING"),
-		},
-		{
-			"Decode row as STRUCT to Go struct with no field for the PK column",
-			&struct {
-				PK1 string `spanner:"_STRING"`
-			}{},
-			errNoOrDupGoField(&struct {
-				PK1 string `spanner:"_STRING"`
-			}{}, "STRING"),
-		},
-		{
-			"Decode row as STRUCT to Go struct with wrong type for the PK column",
-			&struct {
-				PK1 int64 `spanner:"STRING"`
-			}{},
-			errDecodeStructField(&sppb.StructType{Fields: row.fields}, "STRING",
-				errTypeMismatch(sppb.TypeCode_STRING, false, proto.Int64(0))),
-		},
-	} {
-		if gotErr := row.ToStruct(test.dst); !reflect.DeepEqual(gotErr, test.wantErr) {
-			t.Errorf("%v: decoding:\ngot  %v\nwant %v", test.desc, gotErr, test.wantErr)
-		}
-	}
-}
-
-// Test decoding a broken row.
-func TestBrokenRow(t *testing.T) {
-	for i, test := range []struct {
-		row     *Row
-		dst     interface{}
-		wantErr error
-	}{
-		{
-			// A row with no field.
-			&Row{
-				[]*sppb.StructType_Field{},
-				[]*proto3.Value{stringProto("value")},
-			},
-			&NullString{"value", true},
-			errFieldsMismatchVals(&Row{
-				[]*sppb.StructType_Field{},
-				[]*proto3.Value{stringProto("value")},
-			}),
-		},
-		{
-			// A row with nil field.
-			&Row{
-				[]*sppb.StructType_Field{nil},
-				[]*proto3.Value{stringProto("value")},
-			},
-			&NullString{"value", true},
-			errNilColType(0),
-		},
-		{
-			// Field is not nil, but its type is nil.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						nil,
-					},
-				},
-				[]*proto3.Value{listProto(stringProto("value1"), stringProto("value2"))},
-			},
-			&[]NullString{},
-			errDecodeColumn(0, errNilSpannerType()),
-		},
-		{
-			// Field is not nil, field type is not nil, but it is an array and its array element type is nil.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						&sppb.Type{
-							Code: sppb.TypeCode_ARRAY,
-						},
-					},
-				},
-				[]*proto3.Value{listProto(stringProto("value1"), stringProto("value2"))},
-			},
-			&[]NullString{},
-			errDecodeColumn(0, errNilArrElemType(&sppb.Type{Code: sppb.TypeCode_ARRAY})),
-		},
-		{
-			// Field specifies valid type, value is nil.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						intType(),
-					},
-				},
-				[]*proto3.Value{nil},
-			},
-			&NullInt64{1, true},
-			errDecodeColumn(0, errNilSrc()),
-		},
-		{
-			// Field specifies INT64 type, value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						intType(),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_StringValue)(nil)}},
-			},
-			&NullInt64{1, true},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_StringValue)(nil)}, "String")),
-		},
-		{
-			// Field specifies INT64 type, but value is for Number type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						intType(),
-					},
-				},
-				[]*proto3.Value{floatProto(1.0)},
-			},
-			&NullInt64{1, true},
-			errDecodeColumn(0, errSrcVal(floatProto(1.0), "String")),
-		},
-		{
-			// Field specifies INT64 type, but value is wrongly encoded.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						intType(),
-					},
-				},
-				[]*proto3.Value{stringProto("&1")},
-			},
-			proto.Int64(0),
-			errDecodeColumn(0, errBadEncoding(stringProto("&1"), func() error {
-				_, err := strconv.ParseInt("&1", 10, 64)
-				return err
-			}())),
-		},
-		{
-			// Field specifies INT64 type, but value is wrongly encoded.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						intType(),
-					},
-				},
-				[]*proto3.Value{stringProto("&1")},
-			},
-			&NullInt64{},
-			errDecodeColumn(0, errBadEncoding(stringProto("&1"), func() error {
-				_, err := strconv.ParseInt("&1", 10, 64)
-				return err
-			}())),
-		},
-		{
-			// Field specifies STRING type, but value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						stringType(),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_StringValue)(nil)}},
-			},
-			&NullString{"value", true},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_StringValue)(nil)}, "String")),
-		},
-		{
-			// Field specifies STRING type, but value is for ARRAY type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						stringType(),
-					},
-				},
-				[]*proto3.Value{listProto(stringProto("value"))},
-			},
-			&NullString{"value", true},
-			errDecodeColumn(0, errSrcVal(listProto(stringProto("value")), "String")),
-		},
-		{
-			// Field specifies FLOAT64 type, value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						floatType(),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_NumberValue)(nil)}},
-			},
-			&NullFloat64{1.0, true},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_NumberValue)(nil)}, "Number")),
-		},
-		{
-			// Field specifies FLOAT64 type, but value is for BOOL type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						floatType(),
-					},
-				},
-				[]*proto3.Value{boolProto(true)},
-			},
-			&NullFloat64{1.0, true},
-			errDecodeColumn(0, errSrcVal(boolProto(true), "Number")),
-		},
-		{
-			// Field specifies FLOAT64 type, but value is wrongly encoded.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						floatType(),
-					},
-				},
-				[]*proto3.Value{stringProto("nan")},
-			},
-			&NullFloat64{},
-			errDecodeColumn(0, errUnexpectedNumStr("nan")),
-		},
-		{
-			// Field specifies FLOAT64 type, but value is wrongly encoded.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						floatType(),
-					},
-				},
-				[]*proto3.Value{stringProto("nan")},
-			},
-			proto.Float64(0),
-			errDecodeColumn(0, errUnexpectedNumStr("nan")),
-		},
-		{
-			// Field specifies BYTES type, value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						bytesType(),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_StringValue)(nil)}},
-			},
-			&[]byte{},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_StringValue)(nil)}, "String")),
-		},
-		{
-			// Field specifies BYTES type, but value is for BOOL type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						bytesType(),
-					},
-				},
-				[]*proto3.Value{boolProto(false)},
-			},
-			&[]byte{},
-			errDecodeColumn(0, errSrcVal(boolProto(false), "String")),
-		},
-		{
-			// Field specifies BYTES type, but value is wrongly encoded.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						bytesType(),
-					},
-				},
-				[]*proto3.Value{stringProto("&&")},
-			},
-			&[]byte{},
-			errDecodeColumn(0, errBadEncoding(stringProto("&&"), func() error {
-				_, err := base64.StdEncoding.DecodeString("&&")
-				return err
-			}())),
-		},
-		{
-			// Field specifies BOOL type, value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						boolType(),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_BoolValue)(nil)}},
-			},
-			&NullBool{false, true},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_BoolValue)(nil)}, "Bool")),
-		},
-		{
-			// Field specifies BOOL type, but value is for STRING type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						boolType(),
-					},
-				},
-				[]*proto3.Value{stringProto("false")},
-			},
-			&NullBool{false, true},
-			errDecodeColumn(0, errSrcVal(stringProto("false"), "Bool")),
-		},
-		{
-			// Field specifies TIMESTAMP type, value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						timeType(),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_StringValue)(nil)}},
-			},
-			&NullTime{time.Now(), true},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_StringValue)(nil)}, "String")),
-		},
-		{
-			// Field specifies TIMESTAMP type, but value is for BOOL type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						timeType(),
-					},
-				},
-				[]*proto3.Value{boolProto(false)},
-			},
-			&NullTime{time.Now(), true},
-			errDecodeColumn(0, errSrcVal(boolProto(false), "String")),
-		},
-		{
-			// Field specifies TIMESTAMP type, but value is invalid timestamp.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						timeType(),
-					},
-				},
-				[]*proto3.Value{stringProto("junk")},
-			},
-			&NullTime{time.Now(), true},
-			errDecodeColumn(0, errBadEncoding(stringProto("junk"), func() error {
-				_, err := time.Parse(time.RFC3339Nano, "junk")
-				return err
-			}())),
-		},
-		{
-			// Field specifies DATE type, value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						dateType(),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_StringValue)(nil)}},
-			},
-			&NullDate{civil.Date{}, true},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_StringValue)(nil)}, "String")),
-		},
-		{
-			// Field specifies DATE type, but value is for BOOL type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						dateType(),
-					},
-				},
-				[]*proto3.Value{boolProto(false)},
-			},
-			&NullDate{civil.Date{}, true},
-			errDecodeColumn(0, errSrcVal(boolProto(false), "String")),
-		},
-		{
-			// Field specifies DATE type, but value is invalid timestamp.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						dateType(),
-					},
-				},
-				[]*proto3.Value{stringProto("junk")},
-			},
-			&NullDate{civil.Date{}, true},
-			errDecodeColumn(0, errBadEncoding(stringProto("junk"), func() error {
-				_, err := civil.ParseDate("junk")
-				return err
-			}())),
-		},
-
-		{
-			// Field specifies ARRAY<INT64> type, value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(intType()),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_ListValue)(nil)}},
-			},
-			&[]NullInt64{},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_ListValue)(nil)}, "List")),
-		},
-		{
-			// Field specifies ARRAY<INT64> type, value is having a nil ListValue.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(intType()),
-					},
-				},
-				[]*proto3.Value{{Kind: &proto3.Value_ListValue{}}},
-			},
-			&[]NullInt64{},
-			errDecodeColumn(0, errNilListValue("INT64")),
-		},
-		{
-			// Field specifies ARRAY<INT64> type, but value is for BYTES type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(intType()),
-					},
-				},
-				[]*proto3.Value{bytesProto([]byte("value"))},
-			},
-			&[]NullInt64{},
-			errDecodeColumn(0, errSrcVal(bytesProto([]byte("value")), "List")),
-		},
-		{
-			// Field specifies ARRAY<INT64> type, but value is for ARRAY<BOOL> type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(intType()),
-					},
-				},
-				[]*proto3.Value{listProto(boolProto(true))},
-			},
-			&[]NullInt64{},
-			errDecodeColumn(0, errDecodeArrayElement(0, boolProto(true),
-				"INT64", errSrcVal(boolProto(true), "String"))),
-		},
-		{
-			// Field specifies ARRAY<STRING> type, value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(stringType()),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_ListValue)(nil)}},
-			},
-			&[]NullString{},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_ListValue)(nil)}, "List")),
-		},
-		{
-			// Field specifies ARRAY<STRING> type, value is having a nil ListValue.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(stringType()),
-					},
-				},
-				[]*proto3.Value{{Kind: &proto3.Value_ListValue{}}},
-			},
-			&[]NullString{},
-			errDecodeColumn(0, errNilListValue("STRING")),
-		},
-		{
-			// Field specifies ARRAY<STRING> type, but value is for BOOL type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(stringType()),
-					},
-				},
-				[]*proto3.Value{boolProto(true)},
-			},
-			&[]NullString{},
-			errDecodeColumn(0, errSrcVal(boolProto(true), "List")),
-		},
-		{
-			// Field specifies ARRAY<STRING> type, but value is for ARRAY<BOOL> type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(stringType()),
-					},
-				},
-				[]*proto3.Value{listProto(boolProto(true))},
-			},
-			&[]NullString{},
-			errDecodeColumn(0, errDecodeArrayElement(0, boolProto(true),
-				"STRING", errSrcVal(boolProto(true), "String"))),
-		},
-		{
-			// Field specifies ARRAY<FLOAT64> type, value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(floatType()),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_ListValue)(nil)}},
-			},
-			&[]NullFloat64{},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_ListValue)(nil)}, "List")),
-		},
-		{
-			// Field specifies ARRAY<FLOAT64> type, value is having a nil ListValue.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(floatType()),
-					},
-				},
-				[]*proto3.Value{{Kind: &proto3.Value_ListValue{}}},
-			},
-			&[]NullFloat64{},
-			errDecodeColumn(0, errNilListValue("FLOAT64")),
-		},
-		{
-			// Field specifies ARRAY<FLOAT64> type, but value is for STRING type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(floatType()),
-					},
-				},
-				[]*proto3.Value{stringProto("value")},
-			},
-			&[]NullFloat64{},
-			errDecodeColumn(0, errSrcVal(stringProto("value"), "List")),
-		},
-		{
-			// Field specifies ARRAY<FLOAT64> type, but value is for ARRAY<BOOL> type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(floatType()),
-					},
-				},
-				[]*proto3.Value{listProto(boolProto(true))},
-			},
-			&[]NullFloat64{},
-			errDecodeColumn(0, errDecodeArrayElement(0, boolProto(true),
-				"FLOAT64", errSrcVal(boolProto(true), "Number"))),
-		},
-		{
-			// Field specifies ARRAY<BYTES> type, value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(bytesType()),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_ListValue)(nil)}},
-			},
-			&[][]byte{},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_ListValue)(nil)}, "List")),
-		},
-		{
-			// Field specifies ARRAY<BYTES> type, value is having a nil ListValue.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(bytesType()),
-					},
-				},
-				[]*proto3.Value{{Kind: &proto3.Value_ListValue{}}},
-			},
-			&[][]byte{},
-			errDecodeColumn(0, errNilListValue("BYTES")),
-		},
-		{
-			// Field specifies ARRAY<BYTES> type, but value is for FLOAT64 type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(bytesType()),
-					},
-				},
-				[]*proto3.Value{floatProto(1.0)},
-			},
-			&[][]byte{},
-			errDecodeColumn(0, errSrcVal(floatProto(1.0), "List")),
-		},
-		{
-			// Field specifies ARRAY<BYTES> type, but value is for ARRAY<FLOAT64> type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(bytesType()),
-					},
-				},
-				[]*proto3.Value{listProto(floatProto(1.0))},
-			},
-			&[][]byte{},
-			errDecodeColumn(0, errDecodeArrayElement(0, floatProto(1.0),
-				"BYTES", errSrcVal(floatProto(1.0), "String"))),
-		},
-		{
-			// Field specifies ARRAY<BOOL> type, value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(boolType()),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_ListValue)(nil)}},
-			},
-			&[]NullBool{},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_ListValue)(nil)}, "List")),
-		},
-		{
-			// Field specifies ARRAY<BOOL> type, value is having a nil ListValue.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(boolType()),
-					},
-				},
-				[]*proto3.Value{{Kind: &proto3.Value_ListValue{}}},
-			},
-			&[]NullBool{},
-			errDecodeColumn(0, errNilListValue("BOOL")),
-		},
-		{
-			// Field specifies ARRAY<BOOL> type, but value is for FLOAT64 type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(boolType()),
-					},
-				},
-				[]*proto3.Value{floatProto(1.0)},
-			},
-			&[]NullBool{},
-			errDecodeColumn(0, errSrcVal(floatProto(1.0), "List")),
-		},
-		{
-			// Field specifies ARRAY<BOOL> type, but value is for ARRAY<FLOAT64> type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(boolType()),
-					},
-				},
-				[]*proto3.Value{listProto(floatProto(1.0))},
-			},
-			&[]NullBool{},
-			errDecodeColumn(0, errDecodeArrayElement(0, floatProto(1.0),
-				"BOOL", errSrcVal(floatProto(1.0), "Bool"))),
-		},
-		{
-			// Field specifies ARRAY<TIMESTAMP> type, value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(timeType()),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_ListValue)(nil)}},
-			},
-			&[]NullTime{},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_ListValue)(nil)}, "List")),
-		},
-		{
-			// Field specifies ARRAY<TIMESTAMP> type, value is having a nil ListValue.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(timeType()),
-					},
-				},
-				[]*proto3.Value{{Kind: &proto3.Value_ListValue{}}},
-			},
-			&[]NullTime{},
-			errDecodeColumn(0, errNilListValue("TIMESTAMP")),
-		},
-		{
-			// Field specifies ARRAY<TIMESTAMP> type, but value is for FLOAT64 type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(timeType()),
-					},
-				},
-				[]*proto3.Value{floatProto(1.0)},
-			},
-			&[]NullTime{},
-			errDecodeColumn(0, errSrcVal(floatProto(1.0), "List")),
-		},
-		{
-			// Field specifies ARRAY<TIMESTAMP> type, but value is for ARRAY<FLOAT64> type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(timeType()),
-					},
-				},
-				[]*proto3.Value{listProto(floatProto(1.0))},
-			},
-			&[]NullTime{},
-			errDecodeColumn(0, errDecodeArrayElement(0, floatProto(1.0),
-				"TIMESTAMP", errSrcVal(floatProto(1.0), "String"))),
-		},
-		{
-			// Field specifies ARRAY<DATE> type, value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(dateType()),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_ListValue)(nil)}},
-			},
-			&[]NullDate{},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_ListValue)(nil)}, "List")),
-		},
-		{
-			// Field specifies ARRAY<DATE> type, value is having a nil ListValue.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(dateType()),
-					},
-				},
-				[]*proto3.Value{{Kind: &proto3.Value_ListValue{}}},
-			},
-			&[]NullDate{},
-			errDecodeColumn(0, errNilListValue("DATE")),
-		},
-		{
-			// Field specifies ARRAY<DATE> type, but value is for FLOAT64 type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(dateType()),
-					},
-				},
-				[]*proto3.Value{floatProto(1.0)},
-			},
-			&[]NullDate{},
-			errDecodeColumn(0, errSrcVal(floatProto(1.0), "List")),
-		},
-		{
-			// Field specifies ARRAY<DATE> type, but value is for ARRAY<FLOAT64> type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(dateType()),
-					},
-				},
-				[]*proto3.Value{listProto(floatProto(1.0))},
-			},
-			&[]NullDate{},
-			errDecodeColumn(0, errDecodeArrayElement(0, floatProto(1.0),
-				"DATE", errSrcVal(floatProto(1.0), "String"))),
-		},
-		{
-			// Field specifies ARRAY<STRUCT> type, value is having a nil Kind.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(
-							structType(
-								mkField("Col1", intType()),
-								mkField("Col2", floatType()),
-								mkField("Col3", stringType()),
-							),
-						),
-					},
-				},
-				[]*proto3.Value{{Kind: (*proto3.Value_ListValue)(nil)}},
-			},
-			&[]*struct {
-				Col1 int64
-				Col2 float64
-				Col3 string
-			}{},
-			errDecodeColumn(0, errSrcVal(&proto3.Value{Kind: (*proto3.Value_ListValue)(nil)}, "List")),
-		},
-		{
-			// Field specifies ARRAY<STRUCT> type, value is having a nil ListValue.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(
-							structType(
-								mkField("Col1", intType()),
-								mkField("Col2", floatType()),
-								mkField("Col3", stringType()),
-							),
-						),
-					},
-				},
-				[]*proto3.Value{{Kind: &proto3.Value_ListValue{}}},
-			},
-			&[]*struct {
-				Col1 int64
-				Col2 float64
-				Col3 string
-			}{},
-			errDecodeColumn(0, errNilListValue("STRUCT")),
-		},
-		{
-			// Field specifies ARRAY<STRUCT> type, value is having a nil ListValue.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(
-							structType(
-								mkField("Col1", intType()),
-								mkField("Col2", floatType()),
-								mkField("Col3", stringType()),
-							),
-						),
-					},
-				},
-				[]*proto3.Value{{Kind: &proto3.Value_ListValue{}}},
-			},
-			&[]NullRow{},
-			errDecodeColumn(0, errNilListValue("STRUCT")),
-		},
-		{
-			// Field specifies ARRAY<STRUCT> type, value is for BYTES type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(
-							structType(
-								mkField("Col1", intType()),
-								mkField("Col2", floatType()),
-								mkField("Col3", stringType()),
-							),
-						),
-					},
-				},
-				[]*proto3.Value{bytesProto([]byte("value"))},
-			},
-			&[]*struct {
-				Col1 int64
-				Col2 float64
-				Col3 string
-			}{},
-			errDecodeColumn(0, errSrcVal(bytesProto([]byte("value")), "List")),
-		},
-		{
-			// Field specifies ARRAY<STRUCT> type, value is for BYTES type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(
-							structType(
-								mkField("Col1", intType()),
-								mkField("Col2", floatType()),
-								mkField("Col3", stringType()),
-							),
-						),
-					},
-				},
-				[]*proto3.Value{listProto(bytesProto([]byte("value")))},
-			},
-			&[]NullRow{},
-			errDecodeColumn(0, errNotStructElement(0, bytesProto([]byte("value")))),
-		},
-		{
-			// Field specifies ARRAY<STRUCT> type, value is for ARRAY<BYTES> type.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(
-							structType(
-								mkField("Col1", intType()),
-								mkField("Col2", floatType()),
-								mkField("Col3", stringType()),
-							),
-						),
-					},
-				},
-				[]*proto3.Value{listProto(bytesProto([]byte("value")))},
-			},
-			&[]*struct {
-				Col1 int64
-				Col2 float64
-				Col3 string
-			}{},
-			errDecodeColumn(0, errDecodeArrayElement(0, bytesProto([]byte("value")),
-				"STRUCT", errSrcVal(bytesProto([]byte("value")), "List"))),
-		},
-		{
-			// Field specifies ARRAY<STRUCT>, but is having nil StructType.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(
-							&sppb.Type{Code: sppb.TypeCode_STRUCT},
-						),
-					},
-				},
-				[]*proto3.Value{listProto(listProto(intProto(1), floatProto(2.0), stringProto("3")))},
-			},
-			&[]*struct {
-				Col1 int64
-				Col2 float64
-				Col3 string
-			}{},
-			errDecodeColumn(0, errDecodeArrayElement(0, listProto(intProto(1), floatProto(2.0), stringProto("3")),
-				"STRUCT", errNilSpannerStructType())),
-		},
-		{
-			// Field specifies ARRAY<STRUCT>, but the second struct value is for BOOL type instead of FLOAT64.
-			&Row{
-				[]*sppb.StructType_Field{
-					{
-						"Col0",
-						listType(
-							structType(
-								mkField("Col1", intType()),
-								mkField("Col2", floatType()),
-								mkField("Col3", stringType()),
-							),
-						),
-					},
-				},
-				[]*proto3.Value{listProto(listProto(intProto(1), boolProto(true), stringProto("3")))},
-			},
-			&[]*struct {
-				Col1 int64
-				Col2 float64
-				Col3 string
-			}{},
-			errDecodeColumn(
-				0,
-				errDecodeArrayElement(
-					0, listProto(intProto(1), boolProto(true), stringProto("3")), "STRUCT",
-					errDecodeStructField(
-						&sppb.StructType{
-							Fields: []*sppb.StructType_Field{
-								mkField("Col1", intType()),
-								mkField("Col2", floatType()),
-								mkField("Col3", stringType()),
-							},
-						},
-						"Col2",
-						errSrcVal(boolProto(true), "Number"),
-					),
-				),
-			),
-		},
-	} {
-		if gotErr := test.row.Column(0, test.dst); !reflect.DeepEqual(gotErr, test.wantErr) {
-			t.Errorf("%v: test.row.Column(0) got error %v, want %v", i, gotErr, test.wantErr)
-		}
-		if gotErr := test.row.ColumnByName("Col0", test.dst); !reflect.DeepEqual(gotErr, test.wantErr) {
-			t.Errorf("%v: test.row.ColumnByName(%q) got error %v, want %v", i, "Col0", gotErr, test.wantErr)
-		}
-		if gotErr := test.row.Columns(test.dst); !reflect.DeepEqual(gotErr, test.wantErr) {
-			t.Errorf("%v: test.row.Columns(%T) got error %v, want %v", i, test.dst, gotErr, test.wantErr)
-		}
-	}
-}
-
-// Test Row.ToStruct().
-func TestToStruct(t *testing.T) {
-	s := []struct {
-		// STRING / STRING ARRAY
-		PrimaryKey      string       `spanner:"STRING"`
-		NullString      NullString   `spanner:"NULL_STRING"`
-		StringArray     []NullString `spanner:"STRING_ARRAY"`
-		NullStringArray []NullString `spanner:"NULL_STRING_ARRAY"`
-		// BYTES / BYTES ARRAY
-		Bytes          []byte   `spanner:"BYTES"`
-		NullBytes      []byte   `spanner:"NULL_BYTES"`
-		BytesArray     [][]byte `spanner:"BYTES_ARRAY"`
-		NullBytesArray [][]byte `spanner:"NULL_BYTES_ARRAY"`
-		// INT64 / INT64 ARRAY
-		Int64          int64       `spanner:"INT64"`
-		NullInt64      NullInt64   `spanner:"NULL_INT64"`
-		Int64Array     []NullInt64 `spanner:"INT64_ARRAY"`
-		NullInt64Array []NullInt64 `spanner:"NULL_INT64_ARRAY"`
-		// BOOL / BOOL ARRAY
-		Bool          bool       `spanner:"BOOL"`
-		NullBool      NullBool   `spanner:"NULL_BOOL"`
-		BoolArray     []NullBool `spanner:"BOOL_ARRAY"`
-		NullBoolArray []NullBool `spanner:"NULL_BOOL_ARRAY"`
-		// FLOAT64 / FLOAT64 ARRAY
-		Float64          float64       `spanner:"FLOAT64"`
-		NullFloat64      NullFloat64   `spanner:"NULL_FLOAT64"`
-		Float64Array     []NullFloat64 `spanner:"FLOAT64_ARRAY"`
-		NullFloat64Array []NullFloat64 `spanner:"NULL_FLOAT64_ARRAY"`
-		// TIMESTAMP / TIMESTAMP ARRAY
-		Timestamp          time.Time  `spanner:"TIMESTAMP"`
-		NullTimestamp      NullTime   `spanner:"NULL_TIMESTAMP"`
-		TimestampArray     []NullTime `spanner:"TIMESTAMP_ARRAY"`
-		NullTimestampArray []NullTime `spanner:"NULL_TIMESTAMP_ARRAY"`
-		// DATE / DATE ARRAY
-		Date          civil.Date `spanner:"DATE"`
-		NullDate      NullDate   `spanner:"NULL_DATE"`
-		DateArray     []NullDate `spanner:"DATE_ARRAY"`
-		NullDateArray []NullDate `spanner:"NULL_DATE_ARRAY"`
-
-		// STRUCT ARRAY
-		StructArray []*struct {
-			Col1 int64
-			Col2 float64
-			Col3 string
-		} `spanner:"STRUCT_ARRAY"`
-		NullStructArray []*struct {
-			Col1 int64
-			Col2 float64
-			Col3 string
-		} `spanner:"NULL_STRUCT_ARRAY"`
-	}{
-		{}, // got
-		{
-			// STRING / STRING ARRAY
-			"value",
-			NullString{},
-			[]NullString{{"value1", true}, {}, {"value3", true}},
-			[]NullString(nil),
-			// BYTES / BYTES ARRAY
-			[]byte("value"),
-			[]byte(nil),
-			[][]byte{[]byte("value1"), nil, []byte("value3")},
-			[][]byte(nil),
-			// INT64 / INT64 ARRAY
-			int64(17),
-			NullInt64{},
-			[]NullInt64{{int64(1), true}, {int64(2), true}, {}},
-			[]NullInt64(nil),
-			// BOOL / BOOL ARRAY
-			true,
-			NullBool{},
-			[]NullBool{{}, {true, true}, {false, true}},
-			[]NullBool(nil),
-			// FLOAT64 / FLOAT64 ARRAY
-			1.7,
-			NullFloat64{},
-			[]NullFloat64{{}, {}, {1.7, true}},
-			[]NullFloat64(nil),
-			// TIMESTAMP / TIMESTAMP ARRAY
-			tm,
-			NullTime{},
-			[]NullTime{{}, {tm, true}},
-			[]NullTime(nil),
-			// DATE / DATE ARRAY
-			dt,
-			NullDate{},
-			[]NullDate{{}, {dt, true}},
-			[]NullDate(nil),
-			// STRUCT ARRAY
-			[]*struct {
-				Col1 int64
-				Col2 float64
-				Col3 string
-			}{
-				nil,
-				&struct {
-					Col1 int64
-					Col2 float64
-					Col3 string
-				}{3, 33.3, "three"},
-				nil,
-			},
-			[]*struct {
-				Col1 int64
-				Col2 float64
-				Col3 string
-			}(nil),
-		}, // want
-	}
-	err := row.ToStruct(&s[0])
-	if err != nil {
-		t.Errorf("row.ToStruct() returns error: %v, want nil", err)
-	}
-	if !reflect.DeepEqual(s[0], s[1]) {
-		t.Errorf("row.ToStruct() fetches struct %v, want %v", s[0], s[1])
-	}
-}
-
-// Test helpers for getting column names.
-func TestColumnNameAndIndex(t *testing.T) {
-	// Test Row.Size().
-	if rs := row.Size(); rs != len(row.fields) {
-		t.Errorf("row.Size() returns %v, want %v", rs, len(row.fields))
-	}
-	// Test Row.Size() on empty Row.
-	if rs := (&Row{}).Size(); rs != 0 {
-		t.Errorf("empty_row.Size() returns %v, want %v", rs, 0)
-	}
-	// Test Row.ColumnName()
-	for i, col := range row.fields {
-		if cn := row.ColumnName(i); cn != col.Name {
-			t.Errorf("row.ColumnName(%v) returns %q, want %q", i, cn, col.Name)
-		}
-		goti, err := row.ColumnIndex(col.Name)
-		if err != nil {
-			t.Errorf("ColumnIndex(%q) error %v", col.Name, err)
-			continue
-		}
-		if goti != i {
-			t.Errorf("ColumnIndex(%q) = %d, want %d", col.Name, goti, i)
-		}
-	}
-	// Test Row.ColumnName on empty Row.
-	if cn := (&Row{}).ColumnName(0); cn != "" {
-		t.Errorf("empty_row.ColumnName(%v) returns %q, want %q", 0, cn, "")
-	}
-	// Test Row.ColumnIndex on empty Row.
-	if _, err := (&Row{}).ColumnIndex(""); err == nil {
-		t.Error("empty_row.ColumnIndex returns nil, want error")
-	}
-}
-
-func TestNewRow(t *testing.T) {
-	for _, test := range []struct {
-		names   []string
-		values  []interface{}
-		want    *Row
-		wantErr error
-	}{
-		{
-			want: &Row{fields: []*sppb.StructType_Field{}, vals: []*proto3.Value{}},
-		},
-		{
-			names:  []string{},
-			values: []interface{}{},
-			want:   &Row{fields: []*sppb.StructType_Field{}, vals: []*proto3.Value{}},
-		},
-		{
-			names:   []string{"a", "b"},
-			values:  []interface{}{},
-			want:    nil,
-			wantErr: errNamesValuesMismatch([]string{"a", "b"}, []interface{}{}),
-		},
-		{
-			names:  []string{"a", "b", "c"},
-			values: []interface{}{5, "abc", GenericColumnValue{listType(intType()), listProto(intProto(91), nullProto(), intProto(87))}},
-			want: &Row{
-				[]*sppb.StructType_Field{
-					{"a", intType()},
-					{"b", stringType()},
-					{"c", listType(intType())},
-				},
-				[]*proto3.Value{
-					intProto(5),
-					stringProto("abc"),
-					listProto(intProto(91), nullProto(), intProto(87)),
-				},
-			},
-		},
-	} {
-		got, err := NewRow(test.names, test.values)
-		if !reflect.DeepEqual(err, test.wantErr) {
-			t.Errorf("NewRow(%v,%v).err = %s, want %s", test.names, test.values, err, test.wantErr)
-			continue
-		}
-		if !reflect.DeepEqual(got, test.want) {
-			t.Errorf("NewRow(%v,%v) = %s, want %s", test.names, test.values, got, test.want)
-			continue
-		}
-	}
-}
diff --git a/vendor/cloud.google.com/go/spanner/session.go b/vendor/cloud.google.com/go/spanner/session.go
deleted file mode 100644
index 6930a3aba..000000000
--- a/vendor/cloud.google.com/go/spanner/session.go
+++ /dev/null
@@ -1,968 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"container/heap"
-	"container/list"
-	"fmt"
-	"math/rand"
-	"strings"
-	"sync"
-	"time"
-
-	log "github.com/golang/glog"
-	"golang.org/x/net/context"
-
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/metadata"
-)
-
-// sessionHandle is an interface for transactions to access Cloud Spanner sessions safely. It is generated by sessionPool.take().
-type sessionHandle struct {
-	// mu guarantees that inner session object is returned / destroyed only once.
-	mu sync.Mutex
-	// session is a pointer to a session object. Transactions never need to access it directly.
-	session *session
-}
-
-// recycle gives the inner session object back to its home session pool. It is safe to call recycle multiple times but only the first one would take effect.
-func (sh *sessionHandle) recycle() {
-	sh.mu.Lock()
-	defer sh.mu.Unlock()
-	if sh.session == nil {
-		// sessionHandle has already been recycled.
-		return
-	}
-	sh.session.recycle()
-	sh.session = nil
-}
-
-// getID gets the Cloud Spanner session ID from the internal session object. getID returns empty string if the sessionHandle is nil or the inner session
-// object has been released by recycle / destroy.
-func (sh *sessionHandle) getID() string {
-	sh.mu.Lock()
-	defer sh.mu.Unlock()
-	if sh.session == nil {
-		// sessionHandle has already been recycled/destroyed.
-		return ""
-	}
-	return sh.session.getID()
-}
-
-// getClient gets the Cloud Spanner RPC client associated with the session ID in sessionHandle.
-func (sh *sessionHandle) getClient() sppb.SpannerClient {
-	sh.mu.Lock()
-	defer sh.mu.Unlock()
-	if sh.session == nil {
-		return nil
-	}
-	return sh.session.client
-}
-
-// getMetadata returns the metadata associated with the session in sessionHandle.
-func (sh *sessionHandle) getMetadata() metadata.MD {
-	sh.mu.Lock()
-	defer sh.mu.Unlock()
-	if sh.session == nil {
-		return nil
-	}
-	return sh.session.md
-}
-
-// getTransactionID returns the transaction id in the session if available.
-func (sh *sessionHandle) getTransactionID() transactionID {
-	sh.mu.Lock()
-	defer sh.mu.Unlock()
-	if sh.session == nil {
-		return nil
-	}
-	return sh.session.tx
-}
-
-// destroy destroys the inner session object. It is safe to call destroy multiple times and only the first call would attempt to
-// destroy the inner session object.
-func (sh *sessionHandle) destroy() {
-	sh.mu.Lock()
-	s := sh.session
-	sh.session = nil
-	sh.mu.Unlock()
-	if s == nil {
-		// sessionHandle has already been destroyed.
-		return
-	}
-	s.destroy(false)
-}
-
-// session wraps a Cloud Spanner session ID through which transactions are created and executed.
-type session struct {
-	// client is the RPC channel to Cloud Spanner. It is set only once during session's creation.
-	client sppb.SpannerClient
-	// id is the unique id of the session in Cloud Spanner. It is set only once during session's creation.
-	id string
-	// pool is the session's home session pool where it was created. It is set only once during session's creation.
-	pool *sessionPool
-	// createTime is the timestamp of the session's creation. It is set only once during session's creation.
-	createTime time.Time
-
-	// mu protects the following fields from concurrent access: both healthcheck workers and transactions can modify them.
-	mu sync.Mutex
-	// valid marks the validity of a session.
-	valid bool
-	// hcIndex is the index of the session inside the global healthcheck queue. If hcIndex < 0, session has been unregistered from the queue.
-	hcIndex int
-	// idleList is the linkedlist node which links the session to its home session pool's idle list. If idleList == nil, the
-	// session is not in idle list.
-	idleList *list.Element
-	// nextCheck is the timestamp of next scheduled healthcheck of the session. It is maintained by the global health checker.
-	nextCheck time.Time
-	// checkingHelath is true if currently this session is being processed by health checker. Must be modified under health checker lock.
-	checkingHealth bool
-	// md is the Metadata to be sent with each request.
-	md metadata.MD
-	// tx contains the transaction id if the session has been prepared for write.
-	tx transactionID
-}
-
-// isValid returns true if the session is still valid for use.
-func (s *session) isValid() bool {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	return s.valid
-}
-
-// isWritePrepared returns true if the session is prepared for write.
-func (s *session) isWritePrepared() bool {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	return s.tx != nil
-}
-
-// String implements fmt.Stringer for session.
-func (s *session) String() string {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	return fmt.Sprintf("<id=%v, hcIdx=%v, idleList=%p, valid=%v, create=%v, nextcheck=%v>",
-		s.id, s.hcIndex, s.idleList, s.valid, s.createTime, s.nextCheck)
-}
-
-// ping verifies if the session is still alive in Cloud Spanner.
-func (s *session) ping() error {
-	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
-	defer cancel()
-	return runRetryable(ctx, func(ctx context.Context) error {
-		_, err := s.client.GetSession(contextWithOutgoingMetadata(ctx, s.pool.md), &sppb.GetSessionRequest{Name: s.getID()}) // s.getID is safe even when s is invalid.
-		return err
-	})
-}
-
-// refreshIdle refreshes the session's session ID if it is in its home session pool's idle list
-// and returns true if successful.
-func (s *session) refreshIdle() bool {
-	s.mu.Lock()
-	validAndIdle := s.valid && s.idleList != nil
-	s.mu.Unlock()
-	if !validAndIdle {
-		// Optimization: return early if s is not valid or if s is not in idle list.
-		return false
-	}
-	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
-	defer cancel()
-	var sid string
-	err := runRetryable(ctx, func(ctx context.Context) error {
-		session, e := s.client.CreateSession(contextWithOutgoingMetadata(ctx, s.pool.md), &sppb.CreateSessionRequest{Database: s.pool.db})
-		if e != nil {
-			return e
-		}
-		sid = session.Name
-		return nil
-	})
-	if err != nil {
-		return false
-	}
-	s.pool.mu.Lock()
-	s.mu.Lock()
-	var recycle bool
-	if s.valid && s.idleList != nil {
-		// session is in idle list, refresh its session id.
-		sid, s.id = s.id, sid
-		if s.tx != nil {
-			s.tx = nil
-			s.pool.idleWriteList.Remove(s.idleList)
-			// We need to put this session back into the pool.
-			recycle = true
-		}
-	}
-	s.mu.Unlock()
-	s.pool.mu.Unlock()
-	if recycle {
-		s.pool.recycle(s)
-	}
-	// If we fail to explicitly destroy the session, it will be eventually garbage collected by
-	// Cloud Spanner.
-	if err = runRetryable(ctx, func(ctx context.Context) error {
-		_, e := s.client.DeleteSession(contextWithOutgoingMetadata(ctx, s.pool.md), &sppb.DeleteSessionRequest{Name: sid})
-		return e
-	}); err != nil && log.V(2) {
-		log.Warningf("Failed to delete session %v. Error: %v", sid, err)
-	}
-	return true
-}
-
-// setHcIndex atomically sets the session's index in the healthcheck queue and returns the old index.
-func (s *session) setHcIndex(i int) int {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	oi := s.hcIndex
-	s.hcIndex = i
-	return oi
-}
-
-// setIdleList atomically sets the session's idle list link and returns the old link.
-func (s *session) setIdleList(le *list.Element) *list.Element {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	old := s.idleList
-	s.idleList = le
-	return old
-}
-
-// invalidate marks a session as invalid and returns the old validity.
-func (s *session) invalidate() bool {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	ov := s.valid
-	s.valid = false
-	return ov
-}
-
-// setNextCheck sets the timestamp for next healthcheck on the session.
-func (s *session) setNextCheck(t time.Time) {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	s.nextCheck = t
-}
-
-// setTransactionID sets the transaction id in the session
-func (s *session) setTransactionID(tx transactionID) {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	s.tx = tx
-}
-
-// getID returns the session ID which uniquely identifies the session in Cloud Spanner.
-func (s *session) getID() string {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	return s.id
-}
-
-// getHcIndex returns the session's index into the global healthcheck priority queue.
-func (s *session) getHcIndex() int {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	return s.hcIndex
-}
-
-// getIdleList returns the session's link in its home session pool's idle list.
-func (s *session) getIdleList() *list.Element {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	return s.idleList
-}
-
-// getNextCheck returns the timestamp for next healthcheck on the session.
-func (s *session) getNextCheck() time.Time {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	return s.nextCheck
-}
-
-// recycle turns the session back to its home session pool.
-func (s *session) recycle() {
-	s.setTransactionID(nil)
-	if !s.pool.recycle(s) {
-		// s is rejected by its home session pool because it expired and the session pool is currently having enough number of open sessions.
-		s.destroy(false)
-	}
-}
-
-// destroy removes the session from its home session pool, healthcheck queue and Cloud Spanner service.
-func (s *session) destroy(isExpire bool) bool {
-	// Remove s from session pool.
-	if !s.pool.remove(s, isExpire) {
-		return false
-	}
-	// Unregister s from healthcheck queue.
-	s.pool.hc.unregister(s)
-	// Remove s from Cloud Spanner service.
-	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
-	defer cancel()
-	// Ignore the error returned by runRetryable because even if we fail to explicitly destroy the session,
-	// it will be eventually garbage collected by Cloud Spanner.
-	err := runRetryable(ctx, func(ctx context.Context) error {
-		_, e := s.client.DeleteSession(ctx, &sppb.DeleteSessionRequest{Name: s.getID()})
-		return e
-	})
-	if err != nil && log.V(2) {
-		log.Warningf("Failed to delete session %v. Error: %v", s.getID(), err)
-	}
-	return true
-}
-
-// prepareForWrite prepares the session for write if it is not already in that state.
-func (s *session) prepareForWrite(ctx context.Context) error {
-	if s.isWritePrepared() {
-		return nil
-	}
-	tx, err := beginTransaction(ctx, s.getID(), s.client)
-	if err != nil {
-		return err
-	}
-	s.setTransactionID(tx)
-	return nil
-}
-
-// SessionPoolConfig stores configurations of a session pool.
-type SessionPoolConfig struct {
-	// getRPCClient is the caller supplied method for getting a gRPC client to Cloud Spanner, this makes session pool able to use client pooling.
-	getRPCClient func() (sppb.SpannerClient, error)
-	// MaxOpened is the maximum number of opened sessions that is allowed by the
-	// session pool. Default to NumChannels * 100.
-	MaxOpened uint64
-	// MinOpened is the minimum number of opened sessions that the session pool
-	// tries to maintain. Session pool won't continue to expire sessions if number
-	// of opened connections drops below MinOpened. However, if session is found
-	// to be broken, it will still be evicted from session pool, therefore it is
-	// posssible that the number of opened sessions drops below MinOpened.
-	MinOpened uint64
-	// MaxSessionAge is the maximum duration that a session can be reused, zero
-	// means session pool will never expire sessions.
-	MaxSessionAge time.Duration
-	// MaxBurst is the maximum number of concurrent session creation requests. Defaults to 10.
-	MaxBurst uint64
-	// WriteSessions is the fraction of sessions we try to keep prepared for write.
-	WriteSessions float64
-	// HealthCheckWorkers is number of workers used by health checker for this pool.
-	HealthCheckWorkers int
-	// HealthCheckInterval is how often the health checker pings a session.
-	HealthCheckInterval time.Duration
-}
-
-// errNoRPCGetter returns error for SessionPoolConfig missing getRPCClient method.
-func errNoRPCGetter() error {
-	return spannerErrorf(codes.InvalidArgument, "require SessionPoolConfig.getRPCClient != nil, got nil")
-}
-
-// errMinOpenedGTMapOpened returns error for SessionPoolConfig.MaxOpened < SessionPoolConfig.MinOpened when SessionPoolConfig.MaxOpened is set.
-func errMinOpenedGTMaxOpened(spc *SessionPoolConfig) error {
-	return spannerErrorf(codes.InvalidArgument,
-		"require SessionPoolConfig.MaxOpened >= SessionPoolConfig.MinOpened, got %v and %v", spc.MaxOpened, spc.MinOpened)
-}
-
-// validate verifies that the SessionPoolConfig is good for use.
-func (spc *SessionPoolConfig) validate() error {
-	if spc.getRPCClient == nil {
-		return errNoRPCGetter()
-	}
-	if spc.MinOpened > spc.MaxOpened && spc.MaxOpened > 0 {
-		return errMinOpenedGTMaxOpened(spc)
-	}
-	return nil
-}
-
-// sessionPool creates and caches Cloud Spanner sessions.
-type sessionPool struct {
-	// mu protects sessionPool from concurrent access.
-	mu sync.Mutex
-	// valid marks the validity of the session pool.
-	valid bool
-	// db is the database name that all sessions in the pool are associated with.
-	db string
-	// idleList caches idle session IDs. Session IDs in this list can be allocated for use.
-	idleList list.List
-	// idleWriteList caches idle sessions which have been prepared for write.
-	idleWriteList list.List
-	// mayGetSession is for broadcasting that session retrival/creation may proceed.
-	mayGetSession chan struct{}
-	// numOpened is the total number of open sessions from the session pool.
-	numOpened uint64
-	// createReqs is the number of ongoing session creation requests.
-	createReqs uint64
-	// prepareReqs is the number of ongoing session preparation request.
-	prepareReqs uint64
-	// configuration of the session pool.
-	SessionPoolConfig
-	// Metadata to be sent with each request
-	md metadata.MD
-	// hc is the health checker
-	hc *healthChecker
-}
-
-// newSessionPool creates a new session pool.
-func newSessionPool(db string, config SessionPoolConfig, md metadata.MD) (*sessionPool, error) {
-	if err := config.validate(); err != nil {
-		return nil, err
-	}
-	pool := &sessionPool{
-		db:                db,
-		valid:             true,
-		mayGetSession:     make(chan struct{}),
-		SessionPoolConfig: config,
-		md:                md,
-	}
-	if config.HealthCheckWorkers == 0 {
-		// With 10 workers and assuming average latency of 5 ms for BeginTransaction, we will be able to
-		// prepare 2000 tx/sec in advance. If the rate of takeWriteSession is more than that, it will
-		// degrade to doing BeginTransaction inline.
-		// TODO: consider resizing the worker pool dynamically according to the load.
-		config.HealthCheckWorkers = 10
-	}
-	if config.HealthCheckInterval == 0 {
-		config.HealthCheckInterval = 5 * time.Minute
-	}
-	// On GCE VM, within the same region an healthcheck ping takes on average 10ms to finish, given a 5 minutes interval and
-	// 10 healthcheck workers, a healthChecker can effectively mantain 100 checks_per_worker/sec * 10 workers * 300 seconds = 300K sessions.
-	pool.hc = newHealthChecker(config.HealthCheckInterval, config.HealthCheckWorkers, pool)
-	return pool, nil
-}
-
-// isValid checks if the session pool is still valid.
-func (p *sessionPool) isValid() bool {
-	if p == nil {
-		return false
-	}
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	return p.valid
-}
-
-// close marks the session pool as closed.
-func (p *sessionPool) close() {
-	if p == nil {
-		return
-	}
-	p.mu.Lock()
-	if !p.valid {
-		p.mu.Unlock()
-		return
-	}
-	p.valid = false
-	p.mu.Unlock()
-	p.hc.close()
-	// destroy all the sessions
-	p.hc.mu.Lock()
-	allSessions := make([]*session, len(p.hc.queue.sessions))
-	copy(allSessions, p.hc.queue.sessions)
-	p.hc.mu.Unlock()
-	for _, s := range allSessions {
-		s.destroy(false)
-	}
-}
-
-// errInvalidSessionPool returns error for using an invalid session pool.
-func errInvalidSessionPool() error {
-	return spannerErrorf(codes.InvalidArgument, "invalid session pool")
-}
-
-// errGetSessionTimeout returns error for context timeout during sessionPool.take().
-func errGetSessionTimeout() error {
-	return spannerErrorf(codes.Canceled, "timeout / context canceled during getting session")
-}
-
-// shouldPrepareWrite returns true if we should prepare more sessions for write.
-func (p *sessionPool) shouldPrepareWrite() bool {
-	return float64(p.numOpened)*p.WriteSessions > float64(p.idleWriteList.Len()+int(p.prepareReqs))
-}
-
-func (p *sessionPool) createSession(ctx context.Context) (*session, error) {
-	doneCreate := func(done bool) {
-		p.mu.Lock()
-		if !done {
-			// Session creation failed, give budget back.
-			p.numOpened--
-		}
-		p.createReqs--
-		// Notify other waiters blocking on session creation.
-		close(p.mayGetSession)
-		p.mayGetSession = make(chan struct{})
-		p.mu.Unlock()
-	}
-	sc, err := p.getRPCClient()
-	if err != nil {
-		doneCreate(false)
-		return nil, err
-	}
-	var s *session
-	err = runRetryable(ctx, func(ctx context.Context) error {
-		sid, e := sc.CreateSession(ctx, &sppb.CreateSessionRequest{Database: p.db})
-		if e != nil {
-			return e
-		}
-		// If no error, construct the new session.
-		s = &session{valid: true, client: sc, id: sid.Name, pool: p, createTime: time.Now(), md: p.md}
-		p.hc.register(s)
-		return nil
-	})
-	if err != nil {
-		doneCreate(false)
-		// Should return error directly because of the previous retries on CreateSession RPC.
-		return nil, err
-	}
-	doneCreate(true)
-	return s, nil
-}
-
-func (p *sessionPool) isHealthy(s *session) bool {
-	if s.getNextCheck().Add(2 * p.hc.getInterval()).Before(time.Now()) {
-		// TODO: figure out if we need to schedule a new healthcheck worker here.
-		if err := s.ping(); shouldDropSession(err) {
-			// The session is already bad, continue to fetch/create a new one.
-			s.destroy(false)
-			return false
-		}
-		p.hc.scheduledHC(s)
-	}
-	return true
-}
-
-// take returns a cached session if there are available ones; if there isn't any, it tries to allocate a new one.
-// Session returned by take should be used for read operations.
-func (p *sessionPool) take(ctx context.Context) (*sessionHandle, error) {
-	ctx = contextWithOutgoingMetadata(ctx, p.md)
-	for {
-		var (
-			s   *session
-			err error
-		)
-
-		p.mu.Lock()
-		if !p.valid {
-			p.mu.Unlock()
-			return nil, errInvalidSessionPool()
-		}
-		if p.idleList.Len() > 0 {
-			// Idle sessions are available, get one from the top of the idle list.
-			s = p.idleList.Remove(p.idleList.Front()).(*session)
-		} else if p.idleWriteList.Len() > 0 {
-			s = p.idleWriteList.Remove(p.idleWriteList.Front()).(*session)
-		}
-		if s != nil {
-			s.setIdleList(nil)
-			p.mu.Unlock()
-			// From here, session is no longer in idle list, so healthcheck workers won't destroy it.
-			// If healthcheck workers failed to schedule healthcheck for the session timely, do the check here.
-			// Because session check is still much cheaper than session creation, they should be reused as much as possible.
-			if !p.isHealthy(s) {
-				continue
-			}
-			return &sessionHandle{session: s}, nil
-		}
-		// Idle list is empty, block if session pool has reached max session creation concurrency or max number of open sessions.
-		if (p.MaxOpened > 0 && p.numOpened >= p.MaxOpened) || (p.MaxBurst > 0 && p.createReqs >= p.MaxBurst) {
-			mayGetSession := p.mayGetSession
-			p.mu.Unlock()
-			select {
-			case <-ctx.Done():
-				return nil, errGetSessionTimeout()
-			case <-mayGetSession:
-			}
-			continue
-		}
-		// Take budget before the actual session creation.
-		p.numOpened++
-		p.createReqs++
-		p.mu.Unlock()
-		if s, err = p.createSession(ctx); err != nil {
-			return nil, toSpannerError(err)
-		}
-		return &sessionHandle{session: s}, nil
-	}
-}
-
-// takeWriteSession returns a write prepared cached session if there are available ones; if there isn't any, it tries to allocate a new one.
-// Session returned should be used for read write transactions.
-func (p *sessionPool) takeWriteSession(ctx context.Context) (*sessionHandle, error) {
-	ctx = contextWithOutgoingMetadata(ctx, p.md)
-	for {
-		var (
-			s   *session
-			err error
-		)
-
-		p.mu.Lock()
-		if !p.valid {
-			p.mu.Unlock()
-			return nil, errInvalidSessionPool()
-		}
-		if p.idleWriteList.Len() > 0 {
-			// Idle sessions are available, get one from the top of the idle list.
-			s = p.idleWriteList.Remove(p.idleWriteList.Front()).(*session)
-		} else if p.idleList.Len() > 0 {
-			s = p.idleList.Remove(p.idleList.Front()).(*session)
-		}
-		if s != nil {
-			s.setIdleList(nil)
-			p.mu.Unlock()
-			// From here, session is no longer in idle list, so healthcheck workers won't destroy it.
-			// If healthcheck workers failed to schedule healthcheck for the session timely, do the check here.
-			// Because session check is still much cheaper than session creation, they should be reused as much as possible.
-			if !p.isHealthy(s) {
-				continue
-			}
-			if !s.isWritePrepared() {
-				if err = s.prepareForWrite(ctx); err != nil {
-					return nil, toSpannerError(err)
-				}
-			}
-			return &sessionHandle{session: s}, nil
-		}
-		// Idle list is empty, block if session pool has reached max session creation concurrency or max number of open sessions.
-		if (p.MaxOpened > 0 && p.numOpened >= p.MaxOpened) || (p.MaxBurst > 0 && p.createReqs >= p.MaxBurst) {
-			mayGetSession := p.mayGetSession
-			p.mu.Unlock()
-			select {
-			case <-ctx.Done():
-				return nil, errGetSessionTimeout()
-			case <-mayGetSession:
-			}
-			continue
-		}
-
-		// Take budget before the actual session creation.
-		p.numOpened++
-		p.createReqs++
-		p.mu.Unlock()
-		if s, err = p.createSession(ctx); err != nil {
-			return nil, toSpannerError(err)
-		}
-		if err = s.prepareForWrite(ctx); err != nil {
-			return nil, toSpannerError(err)
-		}
-		return &sessionHandle{session: s}, nil
-	}
-}
-
-// recycle puts session s back to the session pool's idle list, it returns true if the session pool successfully recycles session s.
-func (p *sessionPool) recycle(s *session) bool {
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	if !s.isValid() || !p.valid {
-		// Reject the session if session is invalid or pool itself is invalid.
-		return false
-	}
-	if p.MaxSessionAge != 0 && s.createTime.Add(p.MaxSessionAge).Before(time.Now()) && p.numOpened > p.MinOpened {
-		// session expires and number of opened sessions exceeds MinOpened, let the session destroy itself.
-		return false
-	}
-	// Hot sessions will be converging at the front of the list, cold sessions will be evicted by healthcheck workers.
-	if s.isWritePrepared() {
-		s.setIdleList(p.idleWriteList.PushFront(s))
-	} else {
-		s.setIdleList(p.idleList.PushFront(s))
-	}
-	// Broadcast that a session has been returned to idle list.
-	close(p.mayGetSession)
-	p.mayGetSession = make(chan struct{})
-	return true
-}
-
-// remove atomically removes session s from the session pool and invalidates s.
-// If isExpire == true, the removal is triggered by session expiration and in such cases, only idle sessions can be removed.
-func (p *sessionPool) remove(s *session, isExpire bool) bool {
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	if isExpire && (p.numOpened <= p.MinOpened || s.getIdleList() == nil) {
-		// Don't expire session if the session is not in idle list (in use), or if number of open sessions is going below p.MinOpened.
-		return false
-	}
-	ol := s.setIdleList(nil)
-	// If the session is in the idlelist, remove it.
-	if ol != nil {
-		// Remove from whichever list it is in.
-		p.idleList.Remove(ol)
-		p.idleWriteList.Remove(ol)
-	}
-	if s.invalidate() {
-		// Decrease the number of opened sessions.
-		p.numOpened--
-		// Broadcast that a session has been destroyed.
-		close(p.mayGetSession)
-		p.mayGetSession = make(chan struct{})
-		return true
-	}
-	return false
-}
-
-// hcHeap implements heap.Interface. It is used to create the priority queue for session healthchecks.
-type hcHeap struct {
-	sessions []*session
-}
-
-// Len impelemnts heap.Interface.Len.
-func (h hcHeap) Len() int {
-	return len(h.sessions)
-}
-
-// Less implements heap.Interface.Less.
-func (h hcHeap) Less(i, j int) bool {
-	return h.sessions[i].getNextCheck().Before(h.sessions[j].getNextCheck())
-}
-
-// Swap implements heap.Interface.Swap.
-func (h hcHeap) Swap(i, j int) {
-	h.sessions[i], h.sessions[j] = h.sessions[j], h.sessions[i]
-	h.sessions[i].setHcIndex(i)
-	h.sessions[j].setHcIndex(j)
-}
-
-// Push implements heap.Interface.Push.
-func (h *hcHeap) Push(s interface{}) {
-	ns := s.(*session)
-	ns.setHcIndex(len(h.sessions))
-	h.sessions = append(h.sessions, ns)
-}
-
-// Pop implements heap.Interface.Pop.
-func (h *hcHeap) Pop() interface{} {
-	old := h.sessions
-	n := len(old)
-	s := old[n-1]
-	h.sessions = old[:n-1]
-	s.setHcIndex(-1)
-	return s
-}
-
-// healthChecker performs periodical healthchecks on registered sessions.
-type healthChecker struct {
-	// mu protects concurrent access to hcQueue.
-	mu sync.Mutex
-	// queue is the priority queue for session healthchecks. Sessions with lower nextCheck rank higher in the queue.
-	queue hcHeap
-	// interval is the average interval between two healthchecks on a session.
-	interval time.Duration
-	// workers is the number of concurrent healthcheck workers.
-	workers int
-	// waitWorkers waits for all healthcheck workers to exit
-	waitWorkers sync.WaitGroup
-	// pool is the underlying session pool.
-	pool *sessionPool
-	// closed marks if a healthChecker has been closed.
-	closed bool
-}
-
-// newHealthChecker initializes new instance of healthChecker.
-func newHealthChecker(interval time.Duration, workers int, pool *sessionPool) *healthChecker {
-	if workers <= 0 {
-		workers = 1
-	}
-	hc := &healthChecker{
-		interval: interval,
-		workers:  workers,
-		pool:     pool,
-	}
-	for i := 0; i < hc.workers; i++ {
-		hc.waitWorkers.Add(1)
-		go hc.worker(i)
-	}
-	return hc
-}
-
-// close closes the healthChecker and waits for all healthcheck workers to exit.
-func (hc *healthChecker) close() {
-	hc.mu.Lock()
-	hc.closed = true
-	hc.mu.Unlock()
-	hc.waitWorkers.Wait()
-}
-
-// isClosing checks if a healthChecker is already closing.
-func (hc *healthChecker) isClosing() bool {
-	hc.mu.Lock()
-	defer hc.mu.Unlock()
-	return hc.closed
-}
-
-// getInterval gets the healthcheck interval.
-func (hc *healthChecker) getInterval() time.Duration {
-	hc.mu.Lock()
-	defer hc.mu.Unlock()
-	return hc.interval
-}
-
-// scheduledHCLocked schedules next healthcheck on session s with the assumption that hc.mu is being held.
-func (hc *healthChecker) scheduledHCLocked(s *session) {
-	// The next healthcheck will be scheduled after [interval*0.5, interval*1.5) nanoseconds.
-	nsFromNow := rand.Int63n(int64(hc.interval)) + int64(hc.interval)/2
-	s.setNextCheck(time.Now().Add(time.Duration(nsFromNow)))
-	if hi := s.getHcIndex(); hi != -1 {
-		// Session is still being tracked by healthcheck workers.
-		heap.Fix(&hc.queue, hi)
-	}
-}
-
-// scheduledHC schedules next healthcheck on session s. It is safe to be called concurrently.
-func (hc *healthChecker) scheduledHC(s *session) {
-	hc.mu.Lock()
-	defer hc.mu.Unlock()
-	hc.scheduledHCLocked(s)
-}
-
-// register registers a session with healthChecker for periodical healthcheck.
-func (hc *healthChecker) register(s *session) {
-	hc.mu.Lock()
-	defer hc.mu.Unlock()
-	hc.scheduledHCLocked(s)
-	heap.Push(&hc.queue, s)
-}
-
-// unregister unregisters a session from healthcheck queue.
-func (hc *healthChecker) unregister(s *session) {
-	hc.mu.Lock()
-	defer hc.mu.Unlock()
-	oi := s.setHcIndex(-1)
-	if oi >= 0 {
-		heap.Remove(&hc.queue, oi)
-	}
-}
-
-// markDone marks that health check for session has been performed.
-func (hc *healthChecker) markDone(s *session) {
-	hc.mu.Lock()
-	defer hc.mu.Unlock()
-	s.checkingHealth = false
-}
-
-// healthCheck checks the health of the session and pings it if needed.
-func (hc *healthChecker) healthCheck(s *session) {
-	defer hc.markDone(s)
-	if !s.pool.isValid() {
-		// Session pool is closed, perform a garbage collection.
-		s.destroy(false)
-		return
-	}
-	if s.pool.MaxSessionAge != 0 && s.createTime.Add(s.pool.MaxSessionAge).Before(time.Now()) {
-		// Session reaches its maximum age, retire it. Failing that try to refresh it.
-		if s.destroy(true) || !s.refreshIdle() {
-			return
-		}
-	}
-	if err := s.ping(); shouldDropSession(err) {
-		// Ping failed, destroy the session.
-		s.destroy(false)
-	}
-}
-
-// worker performs the healthcheck on sessions in healthChecker's priority queue.
-func (hc *healthChecker) worker(i int) {
-	if log.V(2) {
-		log.Infof("Starting health check worker %v", i)
-	}
-	// Returns a session which we should ping to keep it alive.
-	getNextForPing := func() *session {
-		hc.pool.mu.Lock()
-		defer hc.pool.mu.Unlock()
-		hc.mu.Lock()
-		defer hc.mu.Unlock()
-		if hc.queue.Len() <= 0 {
-			// Queue is empty.
-			return nil
-		}
-		s := hc.queue.sessions[0]
-		if s.getNextCheck().After(time.Now()) && hc.pool.valid {
-			// All sessions have been checked recently.
-			return nil
-		}
-		hc.scheduledHCLocked(s)
-		if !s.checkingHealth {
-			s.checkingHealth = true
-			return s
-		}
-		return nil
-	}
-
-	// Returns a session which we should prepare for write.
-	getNextForTx := func() *session {
-		hc.pool.mu.Lock()
-		defer hc.pool.mu.Unlock()
-		if hc.pool.shouldPrepareWrite() {
-			if hc.pool.idleList.Len() > 0 && hc.pool.valid {
-				hc.mu.Lock()
-				defer hc.mu.Unlock()
-				if hc.pool.idleList.Front().Value.(*session).checkingHealth {
-					return nil
-				}
-				session := hc.pool.idleList.Remove(hc.pool.idleList.Front()).(*session)
-				session.checkingHealth = true
-				hc.pool.prepareReqs++
-				return session
-			}
-		}
-		return nil
-	}
-
-	for {
-		if hc.isClosing() {
-			if log.V(2) {
-				log.Infof("Closing health check worker %v", i)
-			}
-			// Exit when the pool has been closed and all sessions have been destroyed
-			// or when health checker has been closed.
-			hc.waitWorkers.Done()
-			return
-		}
-		ws := getNextForTx()
-		if ws != nil {
-			ctx, cancel := context.WithTimeout(context.Background(), time.Second)
-			defer cancel()
-			ws.prepareForWrite(contextWithOutgoingMetadata(ctx, hc.pool.md))
-			hc.pool.recycle(ws)
-			hc.pool.mu.Lock()
-			hc.pool.prepareReqs--
-			hc.pool.mu.Unlock()
-			hc.markDone(ws)
-		}
-		rs := getNextForPing()
-		if rs == nil {
-			if ws == nil {
-				// No work to be done so sleep to avoid burning cpu
-				pause := int64(100 * time.Millisecond)
-				if pause > int64(hc.interval) {
-					pause = int64(hc.interval)
-				}
-				<-time.After(time.Duration(rand.Int63n(pause) + pause/2))
-			}
-			continue
-		}
-		hc.healthCheck(rs)
-	}
-}
-
-// shouldDropSession returns true if a particular error leads to the removal of a session
-func shouldDropSession(err error) bool {
-	if err == nil {
-		return false
-	}
-	// If a Cloud Spanner can no longer locate the session (for example, if session is garbage collected), then caller
-	// should not try to return the session back into the session pool.
-	// TODO: once gRPC can return auxilary error information, stop parsing the error message.
-	if ErrCode(err) == codes.NotFound && strings.Contains(ErrDesc(err), "Session not found:") {
-		return true
-	}
-	return false
-}
diff --git a/vendor/cloud.google.com/go/spanner/session_test.go b/vendor/cloud.google.com/go/spanner/session_test.go
deleted file mode 100644
index 7c3d4f88e..000000000
--- a/vendor/cloud.google.com/go/spanner/session_test.go
+++ /dev/null
@@ -1,792 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"container/heap"
-	"math/rand"
-	"reflect"
-	"sync"
-	"testing"
-	"time"
-
-	"golang.org/x/net/context"
-
-	"cloud.google.com/go/spanner/internal/testutil"
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
-)
-
-// setup prepares test environment for regular session pool tests.
-func setup(t *testing.T, spc SessionPoolConfig) (sp *sessionPool, sc *testutil.MockCloudSpannerClient, cancel func()) {
-	sc = testutil.NewMockCloudSpannerClient(t)
-	spc.getRPCClient = func() (sppb.SpannerClient, error) {
-		return sc, nil
-	}
-	spc.HealthCheckInterval = 50 * time.Millisecond
-	sp, err := newSessionPool("mockdb", spc, nil)
-	if err != nil {
-		t.Fatalf("cannot create session pool: %v", err)
-	}
-	cancel = func() {
-		sp.close()
-	}
-	return
-}
-
-// TestSessionCreation tests session creation during sessionPool.Take().
-func TestSessionCreation(t *testing.T) {
-	sp, sc, cancel := setup(t, SessionPoolConfig{})
-	defer cancel()
-	// Take three sessions from session pool, this should trigger session pool to create three new sessions.
-	shs := make([]*sessionHandle, 3)
-	// gotDs holds the unique sessions taken from session pool.
-	gotDs := map[string]bool{}
-	for i := 0; i < len(shs); i++ {
-		var err error
-		shs[i], err = sp.take(context.Background())
-		if err != nil {
-			t.Errorf("failed to get session(%v): %v", i, err)
-		}
-		gotDs[shs[i].getID()] = true
-	}
-	if len(gotDs) != len(shs) {
-		t.Errorf("session pool created %v sessions, want %v", len(gotDs), len(shs))
-	}
-	if wantDs := sc.DumpSessions(); !reflect.DeepEqual(gotDs, wantDs) {
-		t.Errorf("session pool creates sessions %v, want %v", gotDs, wantDs)
-	}
-	// Verify that created sessions are recorded correctly in session pool.
-	sp.mu.Lock()
-	if int(sp.numOpened) != len(shs) {
-		t.Errorf("session pool reports %v open sessions, want %v", sp.numOpened, len(shs))
-	}
-	if sp.createReqs != 0 {
-		t.Errorf("session pool reports %v session create requests, want 0", int(sp.createReqs))
-	}
-	sp.mu.Unlock()
-	// Verify that created sessions are tracked correctly by healthcheck queue.
-	hc := sp.hc
-	hc.mu.Lock()
-	if hc.queue.Len() != len(shs) {
-		t.Errorf("healthcheck queue length = %v, want %v", hc.queue.Len(), len(shs))
-	}
-	for _, s := range hc.queue.sessions {
-		if !gotDs[s.getID()] {
-			t.Errorf("session %v is in healthcheck queue, but it is not created by session pool", s.getID())
-		}
-	}
-	hc.mu.Unlock()
-}
-
-// TestTakeFromIdleList tests taking sessions from session pool's idle list.
-func TestTakeFromIdleList(t *testing.T) {
-	sp, sc, cancel := setup(t, SessionPoolConfig{})
-	defer cancel()
-	// Take ten sessions from session pool and recycle them.
-	shs := make([]*sessionHandle, 10)
-	for i := 0; i < len(shs); i++ {
-		var err error
-		shs[i], err = sp.take(context.Background())
-		if err != nil {
-			t.Errorf("failed to get session(%v): %v", i, err)
-		}
-	}
-	for i := 0; i < len(shs); i++ {
-		shs[i].recycle()
-	}
-	// Further session requests from session pool won't cause mockclient to create more sessions.
-	wantSessions := sc.DumpSessions()
-	// Take ten sessions from session pool again, this time all sessions should come from idle list.
-	gotSessions := map[string]bool{}
-	for i := 0; i < len(shs); i++ {
-		sh, err := sp.take(context.Background())
-		if err != nil {
-			t.Errorf("cannot take session from session pool: %v", err)
-		}
-		gotSessions[sh.getID()] = true
-	}
-	if len(gotSessions) != 10 {
-		t.Errorf("got %v unique sessions, want 10", len(gotSessions))
-	}
-	if !reflect.DeepEqual(gotSessions, wantSessions) {
-		t.Errorf("got sessions: %v, want %v", gotSessions, wantSessions)
-	}
-}
-
-// TesttakeWriteSessionFromIdleList tests taking write sessions from session pool's idle list.
-func TestTakeWriteSessionFromIdleList(t *testing.T) {
-	sp, sc, cancel := setup(t, SessionPoolConfig{})
-	defer cancel()
-	act := testutil.NewAction("Begin", nil)
-	acts := make([]testutil.Action, 20)
-	for i := 0; i < len(acts); i++ {
-		acts[i] = act
-	}
-	sc.SetActions(acts...)
-	// Take ten sessions from session pool and recycle them.
-	shs := make([]*sessionHandle, 10)
-	for i := 0; i < len(shs); i++ {
-		var err error
-		shs[i], err = sp.takeWriteSession(context.Background())
-		if err != nil {
-			t.Errorf("failed to get session(%v): %v", i, err)
-		}
-	}
-	for i := 0; i < len(shs); i++ {
-		shs[i].recycle()
-	}
-	// Further session requests from session pool won't cause mockclient to create more sessions.
-	wantSessions := sc.DumpSessions()
-	// Take ten sessions from session pool again, this time all sessions should come from idle list.
-	gotSessions := map[string]bool{}
-	for i := 0; i < len(shs); i++ {
-		sh, err := sp.takeWriteSession(context.Background())
-		if err != nil {
-			t.Errorf("cannot take session from session pool: %v", err)
-		}
-		gotSessions[sh.getID()] = true
-	}
-	if len(gotSessions) != 10 {
-		t.Errorf("got %v unique sessions, want 10", len(gotSessions))
-	}
-	if !reflect.DeepEqual(gotSessions, wantSessions) {
-		t.Errorf("got sessions: %v, want %v", gotSessions, wantSessions)
-	}
-}
-
-// TestTakeFromIdleListChecked tests taking sessions from session pool's idle list, but with a extra ping check.
-func TestTakeFromIdleListChecked(t *testing.T) {
-	if testing.Short() {
-		t.SkipNow()
-	}
-	sp, sc, cancel := setup(t, SessionPoolConfig{})
-	defer cancel()
-	// Stop healthcheck workers to simulate slow pings.
-	sp.hc.close()
-	// Create a session and recycle it.
-	sh, err := sp.take(context.Background())
-	if err != nil {
-		t.Errorf("failed to get session: %v", err)
-	}
-	wantSid := sh.getID()
-	sh.recycle()
-	<-time.After(time.Second)
-	// Two back-to-back session requests, both of them should return the same session created before and
-	// none of them should trigger a session ping.
-	for i := 0; i < 2; i++ {
-		// Take the session from the idle list and recycle it.
-		sh, err = sp.take(context.Background())
-		if err != nil {
-			t.Errorf("%v - failed to get session: %v", i, err)
-		}
-		if gotSid := sh.getID(); gotSid != wantSid {
-			t.Errorf("%v - got session id: %v, want %v", i, gotSid, wantSid)
-		}
-		// The two back-to-back session requests shouldn't trigger any session pings because sessionPool.Take
-		// reschedules the next healthcheck.
-		if got, want := sc.DumpPings(), ([]string{wantSid}); !reflect.DeepEqual(got, want) {
-			t.Errorf("%v - got ping session requests: %v, want %v", i, got, want)
-		}
-		sh.recycle()
-	}
-	// Inject session error to mockclient, and take the session from the session pool, the old session should be destroyed and
-	// the session pool will create a new session.
-	sc.InjectError("GetSession", grpc.Errorf(codes.NotFound, "Session not found:"))
-	// Delay to trigger sessionPool.Take to ping the session.
-	<-time.After(time.Second)
-	sh, err = sp.take(context.Background())
-	if err != nil {
-		t.Errorf("failed to get session: %v", err)
-	}
-	ds := sc.DumpSessions()
-	if len(ds) != 1 {
-		t.Errorf("dumped sessions from mockclient: %v, want %v", ds, sh.getID())
-	}
-	if sh.getID() == wantSid {
-		t.Errorf("sessionPool.Take still returns the same session %v, want it to create a new one", wantSid)
-	}
-}
-
-// TestTakeFromIdleWriteListChecked tests taking sessions from session pool's idle list, but with a extra ping check.
-func TestTakeFromIdleWriteListChecked(t *testing.T) {
-	if testing.Short() {
-		t.SkipNow()
-	}
-	sp, sc, cancel := setup(t, SessionPoolConfig{})
-	defer cancel()
-	sc.MakeNice()
-	// Stop healthcheck workers to simulate slow pings.
-	sp.hc.close()
-	// Create a session and recycle it.
-	sh, err := sp.takeWriteSession(context.Background())
-	if err != nil {
-		t.Errorf("failed to get session: %v", err)
-	}
-	wantSid := sh.getID()
-	sh.recycle()
-	<-time.After(time.Second)
-	// Two back-to-back session requests, both of them should return the same session created before and
-	// none of them should trigger a session ping.
-	for i := 0; i < 2; i++ {
-		// Take the session from the idle list and recycle it.
-		sh, err = sp.takeWriteSession(context.Background())
-		if err != nil {
-			t.Errorf("%v - failed to get session: %v", i, err)
-		}
-		if gotSid := sh.getID(); gotSid != wantSid {
-			t.Errorf("%v - got session id: %v, want %v", i, gotSid, wantSid)
-		}
-		// The two back-to-back session requests shouldn't trigger any session pings because sessionPool.Take
-		// reschedules the next healthcheck.
-		if got, want := sc.DumpPings(), ([]string{wantSid}); !reflect.DeepEqual(got, want) {
-			t.Errorf("%v - got ping session requests: %v, want %v", i, got, want)
-		}
-		sh.recycle()
-	}
-	// Inject session error to mockclient, and take the session from the session pool, the old session should be destroyed and
-	// the session pool will create a new session.
-	sc.InjectError("GetSession", grpc.Errorf(codes.NotFound, "Session not found:"))
-	// Delay to trigger sessionPool.Take to ping the session.
-	<-time.After(time.Second)
-	sh, err = sp.takeWriteSession(context.Background())
-	if err != nil {
-		t.Errorf("failed to get session: %v", err)
-	}
-	ds := sc.DumpSessions()
-	if len(ds) != 1 {
-		t.Errorf("dumped sessions from mockclient: %v, want %v", ds, sh.getID())
-	}
-	if sh.getID() == wantSid {
-		t.Errorf("sessionPool.Take still returns the same session %v, want it to create a new one", wantSid)
-	}
-}
-
-// TestMaxOpenedSessions tests max open sessions constraint.
-func TestMaxOpenedSessions(t *testing.T) {
-	if testing.Short() {
-		t.SkipNow()
-	}
-	sp, _, cancel := setup(t, SessionPoolConfig{MaxOpened: 1})
-	defer cancel()
-	sh1, err := sp.take(context.Background())
-	if err != nil {
-		t.Errorf("cannot take session from session pool: %v", err)
-	}
-	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
-	defer cancel()
-	// Session request will timeout due to the max open sessions constraint.
-	sh2, gotErr := sp.take(ctx)
-	if wantErr := errGetSessionTimeout(); !reflect.DeepEqual(gotErr, wantErr) {
-		t.Errorf("the second session retrival returns error %v, want %v", gotErr, wantErr)
-	}
-	go func() {
-		<-time.After(time.Second)
-		// destroy the first session to allow the next session request to proceed.
-		sh1.destroy()
-	}()
-	// Now session request can be processed because the first session will be destroyed.
-	sh2, err = sp.take(context.Background())
-	if err != nil {
-		t.Errorf("after the first session is destroyed, session retrival still returns error %v, want nil", err)
-	}
-	if !sh2.session.isValid() || sh2.getID() == "" {
-		t.Errorf("got invalid session: %v", sh2.session)
-	}
-}
-
-// TestMinOpenedSessions tests min open session constraint.
-func TestMinOpenedSessions(t *testing.T) {
-	sp, _, cancel := setup(t, SessionPoolConfig{MinOpened: 1})
-	defer cancel()
-	// Take ten sessions from session pool and recycle them.
-	var ss []*session
-	var shs []*sessionHandle
-	for i := 0; i < 10; i++ {
-		sh, err := sp.take(context.Background())
-		if err != nil {
-			t.Errorf("failed to get session(%v): %v", i, err)
-		}
-		ss = append(ss, sh.session)
-		shs = append(shs, sh)
-		sh.recycle()
-	}
-	for _, sh := range shs {
-		sh.recycle()
-	}
-	// Simulate session expiration.
-	for _, s := range ss {
-		s.destroy(true)
-	}
-	sp.mu.Lock()
-	defer sp.mu.Unlock()
-	// There should be still one session left in idle list due to the min open sessions constraint.
-	if sp.idleList.Len() != 1 {
-		t.Errorf("got %v sessions in idle list, want 1", sp.idleList.Len())
-	}
-}
-
-// TestMaxBurst tests max burst constraint.
-func TestMaxBurst(t *testing.T) {
-	if testing.Short() {
-		t.SkipNow()
-	}
-	sp, sc, cancel := setup(t, SessionPoolConfig{MaxBurst: 1})
-	defer cancel()
-	// Will cause session creation RPC to be retried forever.
-	sc.InjectError("CreateSession", grpc.Errorf(codes.Unavailable, "try later"))
-	// This session request will never finish until the injected error is cleared.
-	go sp.take(context.Background())
-	// Poll for the execution of the first session request.
-	for {
-		sp.mu.Lock()
-		cr := sp.createReqs
-		sp.mu.Unlock()
-		if cr == 0 {
-			<-time.After(time.Second)
-			continue
-		}
-		// The first session request is being executed.
-		break
-	}
-	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
-	defer cancel()
-	sh, gotErr := sp.take(ctx)
-	// Since MaxBurst == 1, the second session request should block.
-	if wantErr := errGetSessionTimeout(); !reflect.DeepEqual(gotErr, wantErr) {
-		t.Errorf("session retrival returns error %v, want %v", gotErr, wantErr)
-	}
-	// Let the first session request succeed.
-	sc.InjectError("CreateSession", nil)
-	// Now new session request can proceed because the first session request will eventually succeed.
-	sh, err := sp.take(context.Background())
-	if err != nil {
-		t.Errorf("session retrival returns error %v, want nil", err)
-	}
-	if !sh.session.isValid() || sh.getID() == "" {
-		t.Errorf("got invalid session: %v", sh.session)
-	}
-}
-
-// TestSessionrecycle tests recycling sessions.
-func TestSessionRecycle(t *testing.T) {
-	if testing.Short() {
-		t.SkipNow()
-	}
-	sp, _, cancel := setup(t, SessionPoolConfig{MaxSessionAge: 100 * time.Millisecond, MinOpened: 1})
-	// Healthcheck is explicitly turned off in this test because it might aggressively expire sessions in idle list.
-	sp.hc.close()
-	defer cancel()
-	var ss []*session
-	shs := make([]*sessionHandle, 2)
-	for i := 0; i < len(shs); i++ {
-		var err error
-		shs[i], err = sp.take(context.Background())
-		if err != nil {
-			t.Errorf("cannot get the session %v: %v", i, err)
-		}
-		ss = append(ss, shs[i].session)
-	}
-	// recycle the first session immediately.
-	shs[0].recycle()
-	// Let the second session expire.
-	<-time.After(time.Second)
-	// recycle the second session.
-	shs[1].recycle()
-	// Now the first session should be still valid, but the second session should have been destroyed.
-	if !ss[0].isValid() {
-		t.Errorf("the first session (%v) is invalid, want it to be valid", ss[0])
-	}
-	if ss[1].isValid() {
-		t.Errorf("the second session (%v) is valid, want it to be invalid", ss[1])
-	}
-}
-
-// TestSessionDestroy tests destroying sessions.
-func TestSessionDestroy(t *testing.T) {
-	sp, _, cancel := setup(t, SessionPoolConfig{MinOpened: 1})
-	defer cancel()
-	sh, err := sp.take(context.Background())
-	if err != nil {
-		t.Errorf("cannot get session from session pool: %v", err)
-	}
-	s := sh.session
-	sh.recycle()
-	if d := s.destroy(true); d || !s.isValid() {
-		// Session should be remaining because of min open sessions constraint.
-		t.Errorf("session %v was destroyed in expiration mode, want it to stay alive", s)
-	}
-	if d := s.destroy(false); !d || s.isValid() {
-		// Session should be destroyed.
-		t.Errorf("failed to destroy session %s", s)
-	}
-}
-
-// TestHcHeap tests heap operation on top of hcHeap.
-func TestHcHeap(t *testing.T) {
-	in := []*session{
-		&session{nextCheck: time.Unix(10, 0)},
-		&session{nextCheck: time.Unix(0, 5)},
-		&session{nextCheck: time.Unix(1, 8)},
-		&session{nextCheck: time.Unix(11, 7)},
-		&session{nextCheck: time.Unix(6, 3)},
-	}
-	want := []*session{
-		&session{nextCheck: time.Unix(1, 8), hcIndex: 0},
-		&session{nextCheck: time.Unix(6, 3), hcIndex: 1},
-		&session{nextCheck: time.Unix(8, 2), hcIndex: 2},
-		&session{nextCheck: time.Unix(10, 0), hcIndex: 3},
-		&session{nextCheck: time.Unix(11, 7), hcIndex: 4},
-	}
-	hh := hcHeap{}
-	for _, s := range in {
-		heap.Push(&hh, s)
-	}
-	// Change top of the heap and do a adjustment.
-	hh.sessions[0].nextCheck = time.Unix(8, 2)
-	heap.Fix(&hh, 0)
-	for idx := 0; hh.Len() > 0; idx++ {
-		got := heap.Pop(&hh).(*session)
-		want[idx].hcIndex = -1
-		if !reflect.DeepEqual(got, want[idx]) {
-			t.Errorf("%v: heap.Pop returns %v, want %v", idx, got, want[idx])
-		}
-	}
-}
-
-// TestHealthCheckScheduler tests if healthcheck workers can schedule and perform healthchecks properly.
-func TestHealthCheckScheduler(t *testing.T) {
-	if testing.Short() {
-		t.SkipNow()
-	}
-	sp, sc, cancel := setup(t, SessionPoolConfig{})
-	defer cancel()
-	// Create 50 sessions.
-	ss := []string{}
-	for i := 0; i < 50; i++ {
-		sh, err := sp.take(context.Background())
-		if err != nil {
-			t.Errorf("cannot get session from session pool: %v", err)
-		}
-		ss = append(ss, sh.getID())
-	}
-	// Sleep for 1s, allowing healthcheck workers to perform some session pings.
-	<-time.After(time.Second)
-	dp := sc.DumpPings()
-	gotPings := map[string]int64{}
-	for _, p := range dp {
-		gotPings[p]++
-	}
-	for _, s := range ss {
-		// The average ping interval is 50ms.
-		want := int64(time.Second) / int64(50*time.Millisecond)
-		if got := gotPings[s]; got < want/2 || got > want+want/2 {
-			t.Errorf("got %v healthchecks on session %v, want it between (%v, %v)", got, s, want/2, want+want/2)
-		}
-	}
-}
-
-// Tests that a fractions of sessions are prepared for write by health checker.
-func TestWriteSessionsPrepared(t *testing.T) {
-	if testing.Short() {
-		t.SkipNow()
-	}
-	sp, sc, cancel := setup(t, SessionPoolConfig{WriteSessions: 0.5})
-	sc.MakeNice()
-	defer cancel()
-	shs := make([]*sessionHandle, 10)
-	var err error
-	for i := 0; i < 10; i++ {
-		shs[i], err = sp.take(context.Background())
-		if err != nil {
-			t.Errorf("cannot get session from session pool: %v", err)
-		}
-	}
-	// Now there are 10 sessions in the pool. Release them.
-	for _, sh := range shs {
-		sh.recycle()
-	}
-	// Sleep for 1s, allowing healthcheck workers to invoke begin transaction.
-	<-time.After(time.Second)
-	wshs := make([]*sessionHandle, 5)
-	for i := 0; i < 5; i++ {
-		wshs[i], err = sp.takeWriteSession(context.Background())
-		if err != nil {
-			t.Errorf("cannot get session from session pool: %v", err)
-		}
-		if wshs[i].getTransactionID() == nil {
-			t.Errorf("got nil transaction id from session pool")
-		}
-	}
-	for _, sh := range wshs {
-		sh.recycle()
-	}
-	<-time.After(time.Second)
-	// Now force creation of 10 more sessions.
-	shs = make([]*sessionHandle, 20)
-	for i := 0; i < 20; i++ {
-		shs[i], err = sp.take(context.Background())
-		if err != nil {
-			t.Errorf("cannot get session from session pool: %v", err)
-		}
-	}
-	// Now there are 20 sessions in the pool. Release them.
-	for _, sh := range shs {
-		sh.recycle()
-	}
-	<-time.After(time.Second)
-	if sp.idleWriteList.Len() != 10 {
-		t.Errorf("Expect 10 write prepared session, got: %d", sp.idleWriteList.Len())
-	}
-}
-
-// TestTakeFromWriteQueue tests that sessionPool.take() returns write prepared sessions as well.
-func TestTakeFromWriteQueue(t *testing.T) {
-	if testing.Short() {
-		t.SkipNow()
-	}
-	sp, sc, cancel := setup(t, SessionPoolConfig{MaxOpened: 1, WriteSessions: 1.0})
-	sc.MakeNice()
-	defer cancel()
-	sh, err := sp.take(context.Background())
-	if err != nil {
-		t.Errorf("cannot get session from session pool: %v", err)
-	}
-	sh.recycle()
-	<-time.After(time.Second)
-	// The session should now be in write queue but take should also return it.
-	if sp.idleWriteList.Len() == 0 {
-		t.Errorf("write queue unexpectedly empty")
-	}
-	if sp.idleList.Len() != 0 {
-		t.Errorf("read queue not empty")
-	}
-	sh, err = sp.take(context.Background())
-	if err != nil {
-		t.Errorf("cannot get session from session pool: %v", err)
-	}
-	sh.recycle()
-}
-
-// TestSessionHealthCheck tests healthchecking cases.
-func TestSessionHealthCheck(t *testing.T) {
-	if testing.Short() {
-		t.SkipNow()
-	}
-	sp, sc, cancel := setup(t, SessionPoolConfig{MaxSessionAge: 2 * time.Second})
-	defer cancel()
-	// Test pinging sessions.
-	sh, err := sp.take(context.Background())
-	if err != nil {
-		t.Errorf("cannot get session from session pool: %v", err)
-	}
-	<-time.After(time.Second)
-	pings := sc.DumpPings()
-	if len(pings) == 0 || pings[0] != sh.getID() {
-		t.Errorf("healthchecker didn't send any ping to session %v", sh.getID())
-	}
-	// Test expiring sessions.
-	s := sh.session
-	sh.recycle()
-	// Sleep enough long for session in idle list to expire.
-	<-time.After(2 * time.Second)
-	if s.isValid() {
-		t.Errorf("session(%v) is still alive, want it to expire", s)
-	}
-	// Test broken session detection.
-	sh, err = sp.take(context.Background())
-	if err != nil {
-		t.Errorf("cannot get session from session pool: %v", err)
-	}
-	sc.InjectError("GetSession", grpc.Errorf(codes.NotFound, "Session not found:"))
-	// Wait for healthcheck workers to find the broken session and tear it down.
-	<-time.After(1 * time.Second)
-	if sh.session.isValid() {
-		t.Errorf("session(%v) is still alive, want it to be dropped by healthcheck workers", s)
-	}
-	sc.InjectError("GetSession", nil)
-	// Test garbage collection.
-	sh, err = sp.take(context.Background())
-	if err != nil {
-		t.Errorf("cannot get session from session pool: %v", err)
-	}
-	sp.close()
-	if sh.session.isValid() {
-		t.Errorf("session(%v) is still alive, want it to be garbage collected", s)
-	}
-	// Test session id refresh.
-	// Recreate the session pool with min open sessions constraint.
-	sp, err = newSessionPool("mockdb", SessionPoolConfig{
-		MaxSessionAge: time.Second,
-		MinOpened:     1,
-		getRPCClient: func() (sppb.SpannerClient, error) {
-			return sc, nil
-		},
-		HealthCheckInterval: 50 * time.Millisecond,
-	}, nil)
-	sh, err = sp.take(context.Background())
-	if err != nil {
-		t.Errorf("cannot get session from session pool: %v", err)
-	}
-	oid := sh.getID()
-	s = sh.session
-	sh.recycle()
-	<-time.After(2 * time.Second)
-	nid := s.getID()
-	if nid == "" || nid == oid {
-		t.Errorf("healthcheck workers failed to refresh session: oid=%v, nid=%v", oid, nid)
-	}
-	if gotDs, wantDs := sc.DumpSessions(), (map[string]bool{nid: true}); !reflect.DeepEqual(gotDs, wantDs) {
-		t.Errorf("sessions in mockclient: %v, want %v", gotDs, wantDs)
-	}
-}
-
-// TestStressSessionPool does stress test on session pool by the following concurrent operations:
-//	1) Test worker gets a session from the pool.
-//	2) Test worker turns a session back into the pool.
-//	3) Test worker destroys a session got from the pool.
-//	4) Healthcheck retires an old session from the pool's idlelist by refreshing its session id.
-//	5) Healthcheck destroys a broken session (because a worker has already destroyed it).
-//	6) Test worker closes the session pool.
-//
-// During the test, it is expected that all sessions that are taken from session pool remains valid and
-// when all test workers and healthcheck workers exit, mockclient, session pool and healthchecker should be in consistent state.
-func TestStressSessionPool(t *testing.T) {
-	// Use concurrent workers to test different session pool built from different configurations.
-	if testing.Short() {
-		t.SkipNow()
-	}
-	for ti, cfg := range []SessionPoolConfig{
-		SessionPoolConfig{},
-		SessionPoolConfig{MaxSessionAge: 20 * time.Millisecond},
-		SessionPoolConfig{MinOpened: 10, MaxOpened: 100},
-		SessionPoolConfig{MaxBurst: 50},
-		SessionPoolConfig{MaxSessionAge: 20 * time.Millisecond, MinOpened: 10, MaxOpened: 200, MaxBurst: 5},
-		SessionPoolConfig{MaxSessionAge: 20 * time.Millisecond, MinOpened: 10, MaxOpened: 200, MaxBurst: 5, WriteSessions: 0.2},
-	} {
-		var wg sync.WaitGroup
-		// Create a more aggressive session healthchecker to increase test concurrency.
-		cfg.HealthCheckInterval = 50 * time.Millisecond
-		cfg.HealthCheckWorkers = 50
-		sc := testutil.NewMockCloudSpannerClient(t)
-		sc.MakeNice()
-		cfg.getRPCClient = func() (sppb.SpannerClient, error) {
-			return sc, nil
-		}
-		sp, _ := newSessionPool("mockdb", cfg, nil)
-		for i := 0; i < 100; i++ {
-			wg.Add(1)
-			// Schedule a test worker.
-			go func(idx int, pool *sessionPool, client sppb.SpannerClient) {
-				defer wg.Done()
-				// Test worker iterates 1K times and tries different session / session pool operations.
-				for j := 0; j < 1000; j++ {
-					if idx%10 == 0 && j >= 900 {
-						// Close the pool in selected set of workers during the middle of the test.
-						pool.close()
-					}
-					// Take a write sessions ~ 20% of the times.
-					takeWrite := rand.Intn(5) == 4
-					var (
-						sh     *sessionHandle
-						gotErr error
-					)
-					if takeWrite {
-						sh, gotErr = pool.takeWriteSession(context.Background())
-					} else {
-						sh, gotErr = pool.take(context.Background())
-					}
-					if gotErr != nil {
-						if pool.isValid() {
-							t.Errorf("%v.%v: pool.take returns error when pool is still valid: %v", ti, idx, gotErr)
-						}
-						if wantErr := errInvalidSessionPool(); !reflect.DeepEqual(gotErr, wantErr) {
-							t.Errorf("%v.%v: got error when pool is closed: %v, want %v", ti, idx, gotErr, wantErr)
-						}
-						continue
-					}
-					// Verify if session is valid when session pool is valid. Note that if session pool is invalid after sh is taken,
-					// then sh might be invalidated by healthcheck workers.
-					if (sh.getID() == "" || sh.session == nil || !sh.session.isValid()) && pool.isValid() {
-						t.Errorf("%v.%v.%v: pool.take returns invalid session %v", ti, idx, takeWrite, sh.session)
-					}
-					if takeWrite && sh.getTransactionID() == nil {
-						t.Errorf("%v.%v: pool.takeWriteSession returns session %v without transaction", ti, idx, sh.session)
-					}
-					if int64(cfg.MaxSessionAge) > 0 && rand.Intn(100) < idx {
-						// Random sleep before destroying/recycling the session, to give healthcheck worker a chance to step in.
-						<-time.After(time.Duration(rand.Int63n(int64(cfg.MaxSessionAge))))
-					}
-					if rand.Intn(100) < idx {
-						// destroy the session.
-						sh.destroy()
-						continue
-					}
-					// recycle the session.
-					sh.recycle()
-				}
-			}(i, sp, sc)
-		}
-		wg.Wait()
-		sp.hc.close()
-		// Here the states of healthchecker, session pool and mockclient are stable.
-		idleSessions := map[string]bool{}
-		hcSessions := map[string]bool{}
-		mockSessions := sc.DumpSessions()
-		// Dump session pool's idle list.
-		for sl := sp.idleList.Front(); sl != nil; sl = sl.Next() {
-			s := sl.Value.(*session)
-			if idleSessions[s.getID()] {
-				t.Errorf("%v: found duplicated session in idle list: %v", ti, s.getID())
-			}
-			idleSessions[s.getID()] = true
-		}
-		for sl := sp.idleWriteList.Front(); sl != nil; sl = sl.Next() {
-			s := sl.Value.(*session)
-			if idleSessions[s.getID()] {
-				t.Errorf("%v: found duplicated session in idle write list: %v", ti, s.getID())
-			}
-			idleSessions[s.getID()] = true
-		}
-		if int(sp.numOpened) != len(idleSessions) {
-			t.Errorf("%v: number of opened sessions (%v) != number of idle sessions (%v)", ti, sp.numOpened, len(idleSessions))
-		}
-		if sp.createReqs != 0 {
-			t.Errorf("%v: number of pending session creations = %v, want 0", ti, sp.createReqs)
-		}
-		// Dump healthcheck queue.
-		for _, s := range sp.hc.queue.sessions {
-			if hcSessions[s.getID()] {
-				t.Errorf("%v: found duplicated session in healthcheck queue: %v", ti, s.getID())
-			}
-			hcSessions[s.getID()] = true
-		}
-		// Verify that idleSessions == hcSessions == mockSessions.
-		if !reflect.DeepEqual(idleSessions, hcSessions) {
-			t.Errorf("%v: sessions in idle list (%v) != sessions in healthcheck queue (%v)", ti, idleSessions, hcSessions)
-		}
-		if !reflect.DeepEqual(hcSessions, mockSessions) {
-			t.Errorf("%v: sessions in healthcheck queue (%v) != sessions in mockclient (%v)", ti, hcSessions, mockSessions)
-		}
-		sp.close()
-		mockSessions = sc.DumpSessions()
-		if len(mockSessions) != 0 {
-			t.Errorf("Found live sessions: %v", mockSessions)
-		}
-	}
-}
diff --git a/vendor/cloud.google.com/go/spanner/spanner_test.go b/vendor/cloud.google.com/go/spanner/spanner_test.go
deleted file mode 100644
index ede4e80d2..000000000
--- a/vendor/cloud.google.com/go/spanner/spanner_test.go
+++ /dev/null
@@ -1,1234 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"fmt"
-	"math"
-	"reflect"
-	"strings"
-	"sync"
-	"testing"
-	"time"
-
-	"cloud.google.com/go/civil"
-	"cloud.google.com/go/internal/testutil"
-	database "cloud.google.com/go/spanner/admin/database/apiv1"
-	"golang.org/x/net/context"
-	"google.golang.org/api/iterator"
-	"google.golang.org/api/option"
-	"google.golang.org/grpc/codes"
-
-	adminpb "google.golang.org/genproto/googleapis/spanner/admin/database/v1"
-)
-
-var (
-	// testProjectID specifies the project used for testing.
-	// It can be changed by setting environment variable GCLOUD_TESTS_GOLANG_PROJECT_ID.
-	testProjectID = testutil.ProjID()
-	// testInstanceID specifies the Cloud Spanner instance used for testing.
-	testInstanceID = "go-integration-test"
-
-	// client is a spanner.Client.
-	client *Client
-	// admin is a spanner.DatabaseAdminClient.
-	admin *database.DatabaseAdminClient
-	// db is the path of the testing database.
-	db string
-	// dbName is the short name of the testing database.
-	dbName string
-)
-
-var (
-	singerDBStatements = []string{
-		`CREATE TABLE Singers (
-				SingerId	INT64 NOT NULL,
-				FirstName	STRING(1024),
-				LastName	STRING(1024),
-				SingerInfo	BYTES(MAX)
-			) PRIMARY KEY (SingerId)`,
-		`CREATE INDEX SingerByName ON Singers(FirstName, LastName)`,
-		`CREATE TABLE Accounts (
-				AccountId	INT64 NOT NULL,
-				Nickname	STRING(100),
-				Balance		INT64 NOT NULL,
-			) PRIMARY KEY (AccountId)`,
-		`CREATE INDEX AccountByNickname ON Accounts(Nickname) STORING (Balance)`,
-		`CREATE TABLE Types (
-				RowID		INT64 NOT NULL,
-				String		STRING(MAX),
-				StringArray	ARRAY<STRING(MAX)>,
-				Bytes		BYTES(MAX),
-				BytesArray	ARRAY<BYTES(MAX)>,
-				Int64a		INT64,
-				Int64Array	ARRAY<INT64>,
-				Bool		BOOL,
-				BoolArray	ARRAY<BOOL>,
-				Float64		FLOAT64,
-				Float64Array	ARRAY<FLOAT64>,
-				Date		DATE,
-				DateArray	ARRAY<DATE>,
-				Timestamp	TIMESTAMP,
-				TimestampArray	ARRAY<TIMESTAMP>,
-			) PRIMARY KEY (RowID)`,
-	}
-
-	readDBStatements = []string{
-		`CREATE TABLE TestTable (
-                    Key          STRING(MAX) NOT NULL,
-                    StringValue  STRING(MAX)
-            ) PRIMARY KEY (Key)`,
-		`CREATE INDEX TestTableByValue ON TestTable(StringValue)`,
-		`CREATE INDEX TestTableByValueDesc ON TestTable(StringValue DESC)`,
-	}
-)
-
-type testTableRow struct{ Key, StringValue string }
-
-// prepare initializes Cloud Spanner testing DB and clients.
-func prepare(ctx context.Context, t *testing.T, statements []string) error {
-	if testing.Short() {
-		t.Skip("Integration tests skipped in short mode")
-	}
-	if testProjectID == "" {
-		t.Skip("Integration tests skipped: GCLOUD_TESTS_GOLANG_PROJECT_ID is missing")
-	}
-	ts := testutil.TokenSource(ctx, AdminScope, Scope)
-	if ts == nil {
-		t.Skip("Integration test skipped: cannot get service account credential from environment variable %v", "GCLOUD_TESTS_GOLANG_KEY")
-	}
-	var err error
-	// Create Admin client and Data client.
-	// TODO: Remove the EndPoint option once this is the default.
-	admin, err = database.NewDatabaseAdminClient(ctx, option.WithTokenSource(ts), option.WithEndpoint("spanner.googleapis.com:443"))
-	if err != nil {
-		t.Errorf("cannot create admin client: %v", err)
-		return err
-	}
-	// Construct test DB name.
-	dbName = fmt.Sprintf("gotest_%v", time.Now().UnixNano())
-	db = fmt.Sprintf("projects/%v/instances/%v/databases/%v", testProjectID, testInstanceID, dbName)
-	// Create database and tables.
-	op, err := admin.CreateDatabase(ctx, &adminpb.CreateDatabaseRequest{
-		Parent:          fmt.Sprintf("projects/%v/instances/%v", testProjectID, testInstanceID),
-		CreateStatement: "CREATE DATABASE " + dbName,
-		ExtraStatements: statements,
-	})
-	if err != nil {
-		t.Errorf("cannot create testing DB %v: %v", db, err)
-		return err
-	}
-	if _, err := op.Wait(ctx); err != nil {
-		t.Errorf("cannot create testing DB %v: %v", db, err)
-		return err
-	}
-	client, err = NewClientWithConfig(ctx, db, ClientConfig{
-		SessionPoolConfig: SessionPoolConfig{
-			WriteSessions: 0.2,
-		},
-	}, option.WithTokenSource(ts))
-	if err != nil {
-		t.Errorf("cannot create data client on DB %v: %v", db, err)
-		return err
-	}
-	return nil
-}
-
-// tearDown tears down the testing environment created by prepare().
-func tearDown(ctx context.Context, t *testing.T) {
-	if admin != nil {
-		if err := admin.DropDatabase(ctx, &adminpb.DropDatabaseRequest{db}); err != nil {
-			t.Logf("failed to drop testing database: %v, might need a manual removal", db)
-		}
-		admin.Close()
-	}
-	if client != nil {
-		client.Close()
-	}
-	admin = nil
-	client = nil
-	db = ""
-}
-
-// Test SingleUse transaction.
-func TestSingleUse(t *testing.T) {
-	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
-	defer cancel()
-	// Set up testing environment.
-	if err := prepare(ctx, t, singerDBStatements); err != nil {
-		// If prepare() fails, tear down whatever that's already up.
-		tearDown(ctx, t)
-		t.Fatalf("cannot set up testing environment: %v", err)
-	}
-	// After all tests, tear down testing environment.
-	defer tearDown(ctx, t)
-
-	writes := []struct {
-		row []interface{}
-		ts  time.Time
-	}{
-		{row: []interface{}{1, "Marc", "Foo"}},
-		{row: []interface{}{2, "Tars", "Bar"}},
-		{row: []interface{}{3, "Alpha", "Beta"}},
-		{row: []interface{}{4, "Last", "End"}},
-	}
-	// Try to write four rows through the Apply API.
-	for i, w := range writes {
-		var err error
-		m := InsertOrUpdate("Singers",
-			[]string{"SingerId", "FirstName", "LastName"},
-			w.row)
-		if writes[i].ts, err = client.Apply(ctx, []*Mutation{m}, ApplyAtLeastOnce()); err != nil {
-			t.Fatal(err)
-		}
-	}
-
-	// For testing timestamp bound staleness.
-	<-time.After(time.Second)
-
-	// Test reading rows with different timestamp bounds.
-	for i, test := range []struct {
-		want    [][]interface{}
-		tb      TimestampBound
-		checkTs func(time.Time) error
-	}{
-		{
-			// strong
-			[][]interface{}{{int64(1), "Marc", "Foo"}, {int64(3), "Alpha", "Beta"}, {int64(4), "Last", "End"}},
-			StrongRead(),
-			func(ts time.Time) error {
-				// writes[3] is the last write, all subsequent strong read should have a timestamp larger than that.
-				if ts.Before(writes[3].ts) {
-					return fmt.Errorf("read got timestamp %v, want it to be no later than %v", ts, writes[3].ts)
-				}
-				return nil
-			},
-		},
-		{
-			// min_read_timestamp
-			[][]interface{}{{int64(1), "Marc", "Foo"}, {int64(3), "Alpha", "Beta"}, {int64(4), "Last", "End"}},
-			MinReadTimestamp(writes[3].ts),
-			func(ts time.Time) error {
-				if ts.Before(writes[3].ts) {
-					return fmt.Errorf("read got timestamp %v, want it to be no later than %v", ts, writes[3].ts)
-				}
-				return nil
-			},
-		},
-		{
-			// max_staleness
-			[][]interface{}{{int64(1), "Marc", "Foo"}, {int64(3), "Alpha", "Beta"}, {int64(4), "Last", "End"}},
-			MaxStaleness(time.Second),
-			func(ts time.Time) error {
-				if ts.Before(writes[3].ts) {
-					return fmt.Errorf("read got timestamp %v, want it to be no later than %v", ts, writes[3].ts)
-				}
-				return nil
-			},
-		},
-		{
-			// read_timestamp
-			[][]interface{}{{int64(1), "Marc", "Foo"}, {int64(3), "Alpha", "Beta"}},
-			ReadTimestamp(writes[2].ts),
-			func(ts time.Time) error {
-				if ts != writes[2].ts {
-					return fmt.Errorf("read got timestamp %v, expect %v", ts, writes[2].ts)
-				}
-				return nil
-			},
-		},
-		{
-			// exact_staleness
-			nil,
-			// Specify a staleness which should be already before this test because
-			// context timeout is set to be 10s.
-			ExactStaleness(11 * time.Second),
-			func(ts time.Time) error {
-				if ts.After(writes[0].ts) {
-					return fmt.Errorf("read got timestamp %v, want it to be no earlier than %v", ts, writes[0].ts)
-				}
-				return nil
-			},
-		},
-	} {
-		// SingleUse.Query
-		su := client.Single().WithTimestampBound(test.tb)
-		got, err := readAll(su.Query(
-			ctx,
-			Statement{
-				"SELECT SingerId, FirstName, LastName FROM Singers WHERE SingerId IN (@id1, @id3, @id4)",
-				map[string]interface{}{"id1": int64(1), "id3": int64(3), "id4": int64(4)},
-			}))
-		if err != nil {
-			t.Errorf("%d: SingleUse.Query returns error %v, want nil", i, err)
-		}
-		if !reflect.DeepEqual(got, test.want) {
-			t.Errorf("%d: got unexpected result from SingleUse.Query: %v, want %v", i, got, test.want)
-		}
-		rts, err := su.Timestamp()
-		if err != nil {
-			t.Errorf("%d: SingleUse.Query doesn't return a timestamp, error: %v", i, err)
-		}
-		if err := test.checkTs(rts); err != nil {
-			t.Errorf("%d: SingleUse.Query doesn't return expected timestamp: %v", i, err)
-		}
-		// SingleUse.Read
-		su = client.Single().WithTimestampBound(test.tb)
-		got, err = readAll(su.Read(ctx, "Singers", KeySets(Key{1}, Key{3}, Key{4}), []string{"SingerId", "FirstName", "LastName"}))
-		if err != nil {
-			t.Errorf("%d: SingleUse.Read returns error %v, want nil", i, err)
-		}
-		if !reflect.DeepEqual(got, test.want) {
-			t.Errorf("%d: got unexpected result from SingleUse.Read: %v, want %v", i, got, test.want)
-		}
-		rts, err = su.Timestamp()
-		if err != nil {
-			t.Errorf("%d: SingleUse.Read doesn't return a timestamp, error: %v", i, err)
-		}
-		if err := test.checkTs(rts); err != nil {
-			t.Errorf("%d: SingleUse.Read doesn't return expected timestamp: %v", i, err)
-		}
-		// SingleUse.ReadRow
-		got = nil
-		for _, k := range []Key{Key{1}, Key{3}, Key{4}} {
-			su = client.Single().WithTimestampBound(test.tb)
-			r, err := su.ReadRow(ctx, "Singers", k, []string{"SingerId", "FirstName", "LastName"})
-			if err != nil {
-				continue
-			}
-			v, err := rowToValues(r)
-			if err != nil {
-				continue
-			}
-			got = append(got, v)
-			rts, err = su.Timestamp()
-			if err != nil {
-				t.Errorf("%d: SingleUse.ReadRow(%v) doesn't return a timestamp, error: %v", i, k, err)
-			}
-			if err := test.checkTs(rts); err != nil {
-				t.Errorf("%d: SingleUse.ReadRow(%v) doesn't return expected timestamp: %v", i, k, err)
-			}
-		}
-		if !reflect.DeepEqual(got, test.want) {
-			t.Errorf("%d: got unexpected results from SingleUse.ReadRow: %v, want %v", i, got, test.want)
-		}
-		// SingleUse.ReadUsingIndex
-		su = client.Single().WithTimestampBound(test.tb)
-		got, err = readAll(su.ReadUsingIndex(ctx, "Singers", "SingerByName", KeySets(Key{"Marc", "Foo"}, Key{"Alpha", "Beta"}, Key{"Last", "End"}), []string{"SingerId", "FirstName", "LastName"}))
-		if err != nil {
-			t.Errorf("%d: SingleUse.ReadUsingIndex returns error %v, want nil", i, err)
-		}
-		// The results from ReadUsingIndex is sorted by the index rather than primary key.
-		if len(got) != len(test.want) {
-			t.Errorf("%d: got unexpected result from SingleUse.ReadUsingIndex: %v, want %v", i, got, test.want)
-		}
-		for j, g := range got {
-			if j > 0 {
-				prev := got[j-1][1].(string) + got[j-1][2].(string)
-				curr := got[j][1].(string) + got[j][2].(string)
-				if strings.Compare(prev, curr) > 0 {
-					t.Errorf("%d: SingleUse.ReadUsingIndex fails to order rows by index keys, %v should be after %v", i, got[j-1], got[j])
-				}
-			}
-			found := false
-			for _, w := range test.want {
-				if reflect.DeepEqual(g, w) {
-					found = true
-				}
-			}
-			if !found {
-				t.Errorf("%d: got unexpected result from SingleUse.ReadUsingIndex: %v, want %v", i, got, test.want)
-				break
-			}
-		}
-		rts, err = su.Timestamp()
-		if err != nil {
-			t.Errorf("%d: SingleUse.ReadUsingIndex doesn't return a timestamp, error: %v", i, err)
-		}
-		if err := test.checkTs(rts); err != nil {
-			t.Errorf("%d: SingleUse.ReadUsingIndex doesn't return expected timestamp: %v", i, err)
-		}
-	}
-}
-
-// Test ReadOnlyTransaction. The testsuite is mostly like SingleUse, except it
-// also tests for a single timestamp across multiple reads.
-func TestReadOnlyTransaction(t *testing.T) {
-	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
-	defer cancel()
-	// Set up testing environment.
-	if err := prepare(ctx, t, singerDBStatements); err != nil {
-		// If prepare() fails, tear down whatever that's already up.
-		tearDown(ctx, t)
-		t.Fatalf("cannot set up testing environment: %v", err)
-	}
-	// After all tests, tear down testing environment.
-	defer tearDown(ctx, t)
-
-	writes := []struct {
-		row []interface{}
-		ts  time.Time
-	}{
-		{row: []interface{}{1, "Marc", "Foo"}},
-		{row: []interface{}{2, "Tars", "Bar"}},
-		{row: []interface{}{3, "Alpha", "Beta"}},
-		{row: []interface{}{4, "Last", "End"}},
-	}
-	// Try to write four rows through the Apply API.
-	for i, w := range writes {
-		var err error
-		m := InsertOrUpdate("Singers",
-			[]string{"SingerId", "FirstName", "LastName"},
-			w.row)
-		if writes[i].ts, err = client.Apply(ctx, []*Mutation{m}, ApplyAtLeastOnce()); err != nil {
-			t.Fatal(err)
-		}
-	}
-
-	// For testing timestamp bound staleness.
-	<-time.After(time.Second)
-
-	// Test reading rows with different timestamp bounds.
-	for i, test := range []struct {
-		want    [][]interface{}
-		tb      TimestampBound
-		checkTs func(time.Time) error
-	}{
-		// Note: min_read_timestamp and max_staleness are not supported by ReadOnlyTransaction. See
-		// API document for more details.
-		{
-			// strong
-			[][]interface{}{{int64(1), "Marc", "Foo"}, {int64(3), "Alpha", "Beta"}, {int64(4), "Last", "End"}},
-			StrongRead(),
-			func(ts time.Time) error {
-				if ts.Before(writes[3].ts) {
-					return fmt.Errorf("read got timestamp %v, want it to be no later than %v", ts, writes[3].ts)
-				}
-				return nil
-			},
-		},
-		{
-			// read_timestamp
-			[][]interface{}{{int64(1), "Marc", "Foo"}, {int64(3), "Alpha", "Beta"}},
-			ReadTimestamp(writes[2].ts),
-			func(ts time.Time) error {
-				if ts != writes[2].ts {
-					return fmt.Errorf("read got timestamp %v, expect %v", ts, writes[2].ts)
-				}
-				return nil
-			},
-		},
-		{
-			// exact_staleness
-			nil,
-			// Specify a staleness which should be already before this test because
-			// context timeout is set to be 10s.
-			ExactStaleness(11 * time.Second),
-			func(ts time.Time) error {
-				if ts.After(writes[0].ts) {
-					return fmt.Errorf("read got timestamp %v, want it to be no earlier than %v", ts, writes[0].ts)
-				}
-				return nil
-			},
-		},
-	} {
-		// ReadOnlyTransaction.Query
-		ro := client.ReadOnlyTransaction().WithTimestampBound(test.tb)
-		got, err := readAll(ro.Query(
-			ctx,
-			Statement{
-				"SELECT SingerId, FirstName, LastName FROM Singers WHERE SingerId IN (@id1, @id3, @id4)",
-				map[string]interface{}{"id1": int64(1), "id3": int64(3), "id4": int64(4)},
-			}))
-		if err != nil {
-			t.Errorf("%d: ReadOnlyTransaction.Query returns error %v, want nil", i, err)
-		}
-		if !reflect.DeepEqual(got, test.want) {
-			t.Errorf("%d: got unexpected result from ReadOnlyTransaction.Query: %v, want %v", i, got, test.want)
-		}
-		rts, err := ro.Timestamp()
-		if err != nil {
-			t.Errorf("%d: ReadOnlyTransaction.Query doesn't return a timestamp, error: %v", i, err)
-		}
-		if err := test.checkTs(rts); err != nil {
-			t.Errorf("%d: ReadOnlyTransaction.Query doesn't return expected timestamp: %v", i, err)
-		}
-		roTs := rts
-		// ReadOnlyTransaction.Read
-		got, err = readAll(ro.Read(ctx, "Singers", KeySets(Key{1}, Key{3}, Key{4}), []string{"SingerId", "FirstName", "LastName"}))
-		if err != nil {
-			t.Errorf("%d: ReadOnlyTransaction.Read returns error %v, want nil", i, err)
-		}
-		if !reflect.DeepEqual(got, test.want) {
-			t.Errorf("%d: got unexpected result from ReadOnlyTransaction.Read: %v, want %v", i, got, test.want)
-		}
-		rts, err = ro.Timestamp()
-		if err != nil {
-			t.Errorf("%d: ReadOnlyTransaction.Read doesn't return a timestamp, error: %v", i, err)
-		}
-		if err := test.checkTs(rts); err != nil {
-			t.Errorf("%d: ReadOnlyTransaction.Read doesn't return expected timestamp: %v", i, err)
-		}
-		if roTs != rts {
-			t.Errorf("%d: got two read timestamps: %v, %v, want ReadOnlyTransaction to return always the same read timestamp", i, roTs, rts)
-		}
-		// ReadOnlyTransaction.ReadRow
-		got = nil
-		for _, k := range []Key{Key{1}, Key{3}, Key{4}} {
-			r, err := ro.ReadRow(ctx, "Singers", k, []string{"SingerId", "FirstName", "LastName"})
-			if err != nil {
-				continue
-			}
-			v, err := rowToValues(r)
-			if err != nil {
-				continue
-			}
-			got = append(got, v)
-			rts, err = ro.Timestamp()
-			if err != nil {
-				t.Errorf("%d: ReadOnlyTransaction.ReadRow(%v) doesn't return a timestamp, error: %v", i, k, err)
-			}
-			if err := test.checkTs(rts); err != nil {
-				t.Errorf("%d: ReadOnlyTransaction.ReadRow(%v) doesn't return expected timestamp: %v", i, k, err)
-			}
-			if roTs != rts {
-				t.Errorf("%d: got two read timestamps: %v, %v, want ReadOnlyTransaction to return always the same read timestamp", i, roTs, rts)
-			}
-		}
-		if !reflect.DeepEqual(got, test.want) {
-			t.Errorf("%d: got unexpected results from ReadOnlyTransaction.ReadRow: %v, want %v", i, got, test.want)
-		}
-		// SingleUse.ReadUsingIndex
-		got, err = readAll(ro.ReadUsingIndex(ctx, "Singers", "SingerByName", KeySets(Key{"Marc", "Foo"}, Key{"Alpha", "Beta"}, Key{"Last", "End"}), []string{"SingerId", "FirstName", "LastName"}))
-		if err != nil {
-			t.Errorf("%d: ReadOnlyTransaction.ReadUsingIndex returns error %v, want nil", i, err)
-		}
-		// The results from ReadUsingIndex is sorted by the index rather than primary key.
-		if len(got) != len(test.want) {
-			t.Errorf("%d: got unexpected result from ReadOnlyTransaction.ReadUsingIndex: %v, want %v", i, got, test.want)
-		}
-		for j, g := range got {
-			if j > 0 {
-				prev := got[j-1][1].(string) + got[j-1][2].(string)
-				curr := got[j][1].(string) + got[j][2].(string)
-				if strings.Compare(prev, curr) > 0 {
-					t.Errorf("%d: ReadOnlyTransaction.ReadUsingIndex fails to order rows by index keys, %v should be after %v", i, got[j-1], got[j])
-				}
-			}
-			found := false
-			for _, w := range test.want {
-				if reflect.DeepEqual(g, w) {
-					found = true
-				}
-			}
-			if !found {
-				t.Errorf("%d: got unexpected result from ReadOnlyTransaction.ReadUsingIndex: %v, want %v", i, got, test.want)
-				break
-			}
-		}
-		rts, err = ro.Timestamp()
-		if err != nil {
-			t.Errorf("%d: ReadOnlyTransaction.ReadUsingIndex doesn't return a timestamp, error: %v", i, err)
-		}
-		if err := test.checkTs(rts); err != nil {
-			t.Errorf("%d: ReadOnlyTransaction.ReadUsingIndex doesn't return expected timestamp: %v", i, err)
-		}
-		if roTs != rts {
-			t.Errorf("%d: got two read timestamps: %v, %v, want ReadOnlyTransaction to return always the same read timestamp", i, roTs, rts)
-		}
-		ro.Close()
-	}
-}
-
-// Test ReadWriteTransaction.
-func TestReadWriteTransaction(t *testing.T) {
-	// Give a longer deadline because of transaction backoffs.
-	ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second)
-	defer cancel()
-	if err := prepare(ctx, t, singerDBStatements); err != nil {
-		tearDown(ctx, t)
-		t.Fatalf("cannot set up testing environment: %v", err)
-	}
-	defer tearDown(ctx, t)
-
-	// Set up two accounts
-	accounts := []*Mutation{
-		Insert("Accounts", []string{"AccountId", "Nickname", "Balance"}, []interface{}{int64(1), "Foo", int64(50)}),
-		Insert("Accounts", []string{"AccountId", "Nickname", "Balance"}, []interface{}{int64(2), "Bar", int64(1)}),
-	}
-	if _, err := client.Apply(ctx, accounts, ApplyAtLeastOnce()); err != nil {
-		t.Fatal(err)
-	}
-	wg := sync.WaitGroup{}
-
-	readBalance := func(iter *RowIterator) (int64, error) {
-		defer iter.Stop()
-		var bal int64
-		for {
-			row, err := iter.Next()
-			if err == iterator.Done {
-				return bal, nil
-			}
-			if err != nil {
-				return 0, err
-			}
-			if err := row.Column(0, &bal); err != nil {
-				return 0, err
-			}
-		}
-	}
-
-	for i := 0; i < 20; i++ {
-		wg.Add(1)
-		go func(iter int) {
-			defer wg.Done()
-			_, err := client.ReadWriteTransaction(ctx, func(ctx context.Context, tx *ReadWriteTransaction) error {
-				// Query Foo's balance and Bar's balance.
-				bf, e := readBalance(tx.Query(ctx,
-					Statement{"SELECT Balance FROM Accounts WHERE AccountId = @id", map[string]interface{}{"id": int64(1)}}))
-				if e != nil {
-					return e
-				}
-				bb, e := readBalance(tx.Read(ctx, "Accounts", KeySets(Key{int64(2)}), []string{"Balance"}))
-				if e != nil {
-					return e
-				}
-				if bf <= 0 {
-					return nil
-				}
-				bf--
-				bb++
-				tx.BufferWrite([]*Mutation{
-					Update("Accounts", []string{"AccountId", "Balance"}, []interface{}{int64(1), bf}),
-					Update("Accounts", []string{"AccountId", "Balance"}, []interface{}{int64(2), bb}),
-				})
-				return nil
-			})
-			if err != nil {
-				t.Fatalf("%d: failed to execute transaction: %v", iter, err)
-			}
-		}(i)
-	}
-	// Because of context timeout, all goroutines will eventually return.
-	wg.Wait()
-	_, err := client.ReadWriteTransaction(ctx, func(ctx context.Context, tx *ReadWriteTransaction) error {
-		var bf, bb int64
-		r, e := tx.ReadRow(ctx, "Accounts", Key{int64(1)}, []string{"Balance"})
-		if e != nil {
-			return e
-		}
-		if ce := r.Column(0, &bf); ce != nil {
-			return ce
-		}
-		bb, e = readBalance(tx.ReadUsingIndex(ctx, "Accounts", "AccountByNickname", KeySets(Key{"Bar"}), []string{"Balance"}))
-		if e != nil {
-			return e
-		}
-		if bf != 30 || bb != 21 {
-			t.Errorf("Foo's balance is now %v and Bar's balance is now %v, want %v and %v", bf, bb, 30, 21)
-		}
-		return nil
-	})
-	if err != nil {
-		t.Errorf("failed to check balances: %v", err)
-	}
-}
-
-const (
-	testTable      = "TestTable"
-	testTableIndex = "TestTableByValue"
-)
-
-var testTableColumns = []string{"Key", "StringValue"}
-
-func TestReads(t *testing.T) {
-	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
-	defer cancel()
-	// Set up testing environment.
-	if err := prepare(ctx, t, readDBStatements); err != nil {
-		// If prepare() fails, tear down whatever that's already up.
-		tearDown(ctx, t)
-		t.Fatalf("cannot set up testing environment: %v", err)
-	}
-	// After all tests, tear down testing environment.
-	defer tearDown(ctx, t)
-
-	// Includes k0..k14. Strings sort lexically, eg "k1" < "k10" < "k2".
-	var ms []*Mutation
-	for i := 0; i < 15; i++ {
-		ms = append(ms, InsertOrUpdate(testTable,
-			testTableColumns,
-			[]interface{}{fmt.Sprintf("k%d", i), fmt.Sprintf("v%d", i)}))
-	}
-	if _, err := client.Apply(ctx, ms, ApplyAtLeastOnce()); err != nil {
-		t.Fatal(err)
-	}
-
-	// Empty read.
-	rows, err := readAllTestTable(client.Single().Read(ctx, testTable,
-		KeyRange{Start: Key{"k99"}, End: Key{"z"}}, testTableColumns))
-	if err != nil {
-		t.Fatal(err)
-	}
-	if got, want := len(rows), 0; got != want {
-		t.Errorf("got %d, want %d", got, want)
-	}
-
-	// Index empty read.
-	rows, err = readAllTestTable(client.Single().ReadUsingIndex(ctx, testTable, testTableIndex,
-		KeyRange{Start: Key{"v99"}, End: Key{"z"}}, testTableColumns))
-	if err != nil {
-		t.Fatal(err)
-	}
-	if got, want := len(rows), 0; got != want {
-		t.Errorf("got %d, want %d", got, want)
-	}
-
-	// Point read.
-	row, err := client.Single().ReadRow(ctx, testTable, Key{"k1"}, testTableColumns)
-	if err != nil {
-		t.Fatal(err)
-	}
-	var got testTableRow
-	if err := row.ToStruct(&got); err != nil {
-		t.Fatal(err)
-	}
-	if want := (testTableRow{"k1", "v1"}); got != want {
-		t.Errorf("got %v, want %v", got, want)
-	}
-
-	// Point read not found.
-	_, err = client.Single().ReadRow(ctx, testTable, Key{"k999"}, testTableColumns)
-	if ErrCode(err) != codes.NotFound {
-		t.Fatalf("got %v, want NotFound", err)
-	}
-
-	// No index point read not found, because Go does not have ReadRowUsingIndex.
-
-	rangeReads(ctx, t)
-	indexRangeReads(ctx, t)
-}
-
-func rangeReads(ctx context.Context, t *testing.T) {
-	checkRange := func(ks KeySet, wantNums ...int) {
-		if msg, ok := compareRows(client.Single().Read(ctx, testTable, ks, testTableColumns), wantNums); !ok {
-			t.Errorf("key set %+v: %s", ks, msg)
-		}
-	}
-
-	checkRange(Key{"k1"}, 1)
-	checkRange(KeyRange{Key{"k3"}, Key{"k5"}, ClosedOpen}, 3, 4)
-	checkRange(KeyRange{Key{"k3"}, Key{"k5"}, ClosedClosed}, 3, 4, 5)
-	checkRange(KeyRange{Key{"k3"}, Key{"k5"}, OpenClosed}, 4, 5)
-	checkRange(KeyRange{Key{"k3"}, Key{"k5"}, OpenOpen}, 4)
-
-	// Partial key specification.
-	checkRange(KeyRange{Key{"k7"}, Key{}, ClosedClosed}, 7, 8, 9)
-	checkRange(KeyRange{Key{"k7"}, Key{}, OpenClosed}, 8, 9)
-	checkRange(KeyRange{Key{}, Key{"k11"}, ClosedOpen}, 0, 1, 10)
-	checkRange(KeyRange{Key{}, Key{"k11"}, ClosedClosed}, 0, 1, 10, 11)
-
-	// The following produce empty ranges.
-	// TODO(jba): Consider a multi-part key to illustrate partial key behavior.
-	// checkRange(KeyRange{Key{"k7"}, Key{}, ClosedOpen})
-	// checkRange(KeyRange{Key{"k7"}, Key{}, OpenOpen})
-	// checkRange(KeyRange{Key{}, Key{"k11"}, OpenOpen})
-	// checkRange(KeyRange{Key{}, Key{"k11"}, OpenClosed})
-
-	// Prefix is component-wise, not string prefix.
-	checkRange(Key{"k1"}.AsPrefix(), 1)
-	checkRange(KeyRange{Key{"k1"}, Key{"k2"}, ClosedOpen}, 1, 10, 11, 12, 13, 14)
-
-	checkRange(AllKeys(), 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-}
-
-func indexRangeReads(ctx context.Context, t *testing.T) {
-	checkRange := func(ks KeySet, wantNums ...int) {
-		if msg, ok := compareRows(client.Single().ReadUsingIndex(ctx, testTable, testTableIndex, ks, testTableColumns),
-			wantNums); !ok {
-			t.Errorf("key set %+v: %s", ks, msg)
-		}
-	}
-
-	checkRange(Key{"v1"}, 1)
-	checkRange(KeyRange{Key{"v3"}, Key{"v5"}, ClosedOpen}, 3, 4)
-	checkRange(KeyRange{Key{"v3"}, Key{"v5"}, ClosedClosed}, 3, 4, 5)
-	checkRange(KeyRange{Key{"v3"}, Key{"v5"}, OpenClosed}, 4, 5)
-	checkRange(KeyRange{Key{"v3"}, Key{"v5"}, OpenOpen}, 4)
-
-	// // Partial key specification.
-	checkRange(KeyRange{Key{"v7"}, Key{}, ClosedClosed}, 7, 8, 9)
-	checkRange(KeyRange{Key{"v7"}, Key{}, OpenClosed}, 8, 9)
-	checkRange(KeyRange{Key{}, Key{"v11"}, ClosedOpen}, 0, 1, 10)
-	checkRange(KeyRange{Key{}, Key{"v11"}, ClosedClosed}, 0, 1, 10, 11)
-
-	// // The following produce empty ranges.
-	// checkRange(KeyRange{Key{"v7"}, Key{}, ClosedOpen})
-	// checkRange(KeyRange{Key{"v7"}, Key{}, OpenOpen})
-	// checkRange(KeyRange{Key{}, Key{"v11"}, OpenOpen})
-	// checkRange(KeyRange{Key{}, Key{"v11"}, OpenClosed})
-
-	// // Prefix is component-wise, not string prefix.
-	checkRange(Key{"v1"}.AsPrefix(), 1)
-	checkRange(KeyRange{Key{"v1"}, Key{"v2"}, ClosedOpen}, 1, 10, 11, 12, 13, 14)
-	checkRange(AllKeys(), 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
-	// Read from an index with DESC ordering.
-	wantNums := []int{14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0}
-	if msg, ok := compareRows(client.Single().ReadUsingIndex(ctx, testTable, "TestTableByValueDesc", AllKeys(), testTableColumns),
-		wantNums); !ok {
-		t.Errorf("desc: %s", msg)
-	}
-}
-
-func compareRows(iter *RowIterator, wantNums []int) (string, bool) {
-	rows, err := readAllTestTable(iter)
-	if err != nil {
-		return err.Error(), false
-	}
-	want := map[string]string{}
-	for _, n := range wantNums {
-		want[fmt.Sprintf("k%d", n)] = fmt.Sprintf("v%d", n)
-	}
-	got := map[string]string{}
-	for _, r := range rows {
-		got[r.Key] = r.StringValue
-	}
-	if !reflect.DeepEqual(got, want) {
-		return fmt.Sprintf("got %v, want %v", got, want), false
-	}
-	return "", true
-}
-
-func TestEarlyTimestamp(t *testing.T) {
-	// Test that we can get the timestamp from a read-only transaction as
-	// soon as we have read at least one row.
-	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
-	defer cancel()
-	// Set up testing environment.
-	if err := prepare(ctx, t, readDBStatements); err != nil {
-		// If prepare() fails, tear down whatever that's already up.
-		tearDown(ctx, t)
-		t.Fatalf("cannot set up testing environment: %v", err)
-	}
-	// After all tests, tear down testing environment.
-	defer tearDown(ctx, t)
-
-	var ms []*Mutation
-	for i := 0; i < 3; i++ {
-		ms = append(ms, InsertOrUpdate(testTable,
-			testTableColumns,
-			[]interface{}{fmt.Sprintf("k%d", i), fmt.Sprintf("v%d", i)}))
-	}
-	if _, err := client.Apply(ctx, ms, ApplyAtLeastOnce()); err != nil {
-		t.Fatal(err)
-	}
-
-	txn := client.Single()
-	iter := txn.Read(ctx, testTable, AllKeys(), testTableColumns)
-	defer iter.Stop()
-	// In  single-use transaction, we should get an error before reading anything.
-	if _, err := txn.Timestamp(); err == nil {
-		t.Error("wanted error, got nil")
-	}
-	// After reading one row, the timestamp should be available.
-	_, err := iter.Next()
-	if err != nil {
-		t.Fatal(err)
-	}
-	if _, err := txn.Timestamp(); err != nil {
-		t.Errorf("got %v, want nil", err)
-	}
-
-	txn = client.ReadOnlyTransaction()
-	defer txn.Close()
-	iter = txn.Read(ctx, testTable, AllKeys(), testTableColumns)
-	defer iter.Stop()
-	// In an ordinary read-only transaction, the timestamp should be
-	// available immediately.
-	if _, err := txn.Timestamp(); err != nil {
-		t.Errorf("got %v, want nil", err)
-	}
-}
-
-func TestNestedTransaction(t *testing.T) {
-	// You cannot use a transaction from inside a read-write transaction.
-	ctx := context.Background()
-	if err := prepare(ctx, t, singerDBStatements); err != nil {
-		tearDown(ctx, t)
-		t.Fatalf("cannot set up testing environment: %v", err)
-	}
-	defer tearDown(ctx, t)
-	client.ReadWriteTransaction(ctx, func(ctx context.Context, tx *ReadWriteTransaction) error {
-		_, err := client.ReadWriteTransaction(ctx,
-			func(context.Context, *ReadWriteTransaction) error { return nil })
-		if ErrCode(err) != codes.FailedPrecondition {
-			t.Fatalf("got %v, want FailedPrecondition", err)
-		}
-		_, err = client.Single().ReadRow(ctx, "Singers", Key{1}, []string{"SingerId"})
-		if ErrCode(err) != codes.FailedPrecondition {
-			t.Fatalf("got %v, want FailedPrecondition", err)
-		}
-		rot := client.ReadOnlyTransaction()
-		defer rot.Close()
-		_, err = rot.ReadRow(ctx, "Singers", Key{1}, []string{"SingerId"})
-		if ErrCode(err) != codes.FailedPrecondition {
-			t.Fatalf("got %v, want FailedPrecondition", err)
-		}
-		return nil
-	})
-}
-
-// Test client recovery on database recreation.
-func TestDbRemovalRecovery(t *testing.T) {
-	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
-	defer cancel()
-	if err := prepare(ctx, t, singerDBStatements); err != nil {
-		tearDown(ctx, t)
-		t.Fatalf("cannot set up testing environment: %v", err)
-	}
-	defer tearDown(ctx, t)
-
-	// Drop the testing database.
-	if err := admin.DropDatabase(ctx, &adminpb.DropDatabaseRequest{db}); err != nil {
-		t.Fatalf("failed to drop testing database %v: %v", db, err)
-	}
-
-	// Now, send the query.
-	iter := client.Single().Query(ctx, Statement{SQL: "SELECT SingerId FROM Singers"})
-	defer iter.Stop()
-	if _, err := iter.Next(); err == nil {
-		t.Errorf("client sends query to removed database successfully, want it to fail")
-	}
-
-	// Recreate database and table.
-	op, err := admin.CreateDatabase(ctx, &adminpb.CreateDatabaseRequest{
-		Parent:          fmt.Sprintf("projects/%v/instances/%v", testProjectID, testInstanceID),
-		CreateStatement: "CREATE DATABASE " + dbName,
-		ExtraStatements: []string{
-			`CREATE TABLE Singers (
-				SingerId        INT64 NOT NULL,
-				FirstName       STRING(1024),
-				LastName        STRING(1024),
-				SingerInfo      BYTES(MAX)
-			) PRIMARY KEY (SingerId)`,
-		},
-	})
-	if _, err := op.Wait(ctx); err != nil {
-		t.Errorf("cannot recreate testing DB %v: %v", db, err)
-	}
-
-	// Now, send the query again.
-	iter = client.Single().Query(ctx, Statement{SQL: "SELECT SingerId FROM Singers"})
-	defer iter.Stop()
-	_, err = iter.Next()
-	if err != nil && err != iterator.Done {
-		t.Fatalf("failed to send query to database %v: %v", db, err)
-	}
-}
-
-// Test encoding/decoding non-struct Cloud Spanner types.
-func TestBasicTypes(t *testing.T) {
-	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
-	defer cancel()
-	if err := prepare(ctx, t, singerDBStatements); err != nil {
-		tearDown(ctx, t)
-		t.Fatalf("cannot set up testing environment: %v", err)
-	}
-	defer tearDown(ctx, t)
-	t1, _ := time.Parse(time.RFC3339Nano, "2016-11-15T15:04:05.999999999Z")
-	// Boundaries
-	t2, _ := time.Parse(time.RFC3339Nano, "0001-01-01T00:00:00.000000000Z")
-	t3, _ := time.Parse(time.RFC3339Nano, "9999-12-31T23:59:59.999999999Z")
-	d1, _ := civil.ParseDate("2016-11-15")
-	// Boundaries
-	d2, _ := civil.ParseDate("0001-01-01")
-	d3, _ := civil.ParseDate("9999-12-31")
-
-	tests := []struct {
-		col  string
-		val  interface{}
-		want interface{}
-	}{
-		{col: "String", val: ""},
-		{col: "String", val: "", want: NullString{"", true}},
-		{col: "String", val: "foo"},
-		{col: "String", val: "foo", want: NullString{"foo", true}},
-		{col: "String", val: NullString{"bar", true}, want: "bar"},
-		{col: "String", val: NullString{"bar", false}, want: NullString{"", false}},
-		{col: "StringArray", val: []string(nil), want: []NullString(nil)},
-		{col: "StringArray", val: []string{}, want: []NullString{}},
-		{col: "StringArray", val: []string{"foo", "bar"}, want: []NullString{{"foo", true}, {"bar", true}}},
-		{col: "StringArray", val: []NullString(nil)},
-		{col: "StringArray", val: []NullString{}},
-		{col: "StringArray", val: []NullString{{"foo", true}, {}}},
-		{col: "Bytes", val: []byte{}},
-		{col: "Bytes", val: []byte{1, 2, 3}},
-		{col: "Bytes", val: []byte(nil)},
-		{col: "BytesArray", val: [][]byte(nil)},
-		{col: "BytesArray", val: [][]byte{}},
-		{col: "BytesArray", val: [][]byte{[]byte{1}, []byte{2, 3}}},
-		{col: "Int64a", val: 0, want: int64(0)},
-		{col: "Int64a", val: -1, want: int64(-1)},
-		{col: "Int64a", val: 2, want: int64(2)},
-		{col: "Int64a", val: int64(3)},
-		{col: "Int64a", val: 4, want: NullInt64{4, true}},
-		{col: "Int64a", val: NullInt64{5, true}, want: int64(5)},
-		{col: "Int64a", val: NullInt64{6, true}, want: int64(6)},
-		{col: "Int64a", val: NullInt64{7, false}, want: NullInt64{0, false}},
-		{col: "Int64Array", val: []int(nil), want: []NullInt64(nil)},
-		{col: "Int64Array", val: []int{}, want: []NullInt64{}},
-		{col: "Int64Array", val: []int{1, 2}, want: []NullInt64{{1, true}, {2, true}}},
-		{col: "Int64Array", val: []int64(nil), want: []NullInt64(nil)},
-		{col: "Int64Array", val: []int64{}, want: []NullInt64{}},
-		{col: "Int64Array", val: []int64{1, 2}, want: []NullInt64{{1, true}, {2, true}}},
-		{col: "Int64Array", val: []NullInt64(nil)},
-		{col: "Int64Array", val: []NullInt64{}},
-		{col: "Int64Array", val: []NullInt64{{1, true}, {}}},
-		{col: "Bool", val: false},
-		{col: "Bool", val: true},
-		{col: "Bool", val: false, want: NullBool{false, true}},
-		{col: "Bool", val: true, want: NullBool{true, true}},
-		{col: "Bool", val: NullBool{true, true}},
-		{col: "Bool", val: NullBool{false, false}},
-		{col: "BoolArray", val: []bool(nil), want: []NullBool(nil)},
-		{col: "BoolArray", val: []bool{}, want: []NullBool{}},
-		{col: "BoolArray", val: []bool{true, false}, want: []NullBool{{true, true}, {false, true}}},
-		{col: "BoolArray", val: []NullBool(nil)},
-		{col: "BoolArray", val: []NullBool{}},
-		{col: "BoolArray", val: []NullBool{{false, true}, {true, true}, {}}},
-		{col: "Float64", val: 0.0},
-		{col: "Float64", val: 3.14},
-		{col: "Float64", val: math.NaN()},
-		{col: "Float64", val: math.Inf(1)},
-		{col: "Float64", val: math.Inf(-1)},
-		{col: "Float64", val: 2.78, want: NullFloat64{2.78, true}},
-		{col: "Float64", val: NullFloat64{2.71, true}, want: 2.71},
-		{col: "Float64", val: NullFloat64{1.41, true}, want: NullFloat64{1.41, true}},
-		{col: "Float64", val: NullFloat64{0, false}},
-		{col: "Float64Array", val: []float64(nil), want: []NullFloat64(nil)},
-		{col: "Float64Array", val: []float64{}, want: []NullFloat64{}},
-		{col: "Float64Array", val: []float64{2.72, 3.14, math.Inf(1)}, want: []NullFloat64{{2.72, true}, {3.14, true}, {math.Inf(1), true}}},
-		{col: "Float64Array", val: []NullFloat64(nil)},
-		{col: "Float64Array", val: []NullFloat64{}},
-		{col: "Float64Array", val: []NullFloat64{{2.72, true}, {math.Inf(1), true}, {}}},
-		{col: "Date", val: d1},
-		{col: "Date", val: d1, want: NullDate{d1, true}},
-		{col: "Date", val: NullDate{d1, true}},
-		{col: "Date", val: NullDate{d1, true}, want: d1},
-		{col: "Date", val: NullDate{civil.Date{}, false}},
-		{col: "DateArray", val: []civil.Date(nil), want: []NullDate(nil)},
-		{col: "DateArray", val: []civil.Date{}, want: []NullDate{}},
-		{col: "DateArray", val: []civil.Date{d1, d2, d3}, want: []NullDate{{d1, true}, {d2, true}, {d3, true}}},
-		{col: "Timestamp", val: t1},
-		{col: "Timestamp", val: t1, want: NullTime{t1, true}},
-		{col: "Timestamp", val: NullTime{t1, true}},
-		{col: "Timestamp", val: NullTime{t1, true}, want: t1},
-		{col: "Timestamp", val: NullTime{}},
-		{col: "TimestampArray", val: []time.Time(nil), want: []NullTime(nil)},
-		{col: "TimestampArray", val: []time.Time{}, want: []NullTime{}},
-		{col: "TimestampArray", val: []time.Time{t1, t2, t3}, want: []NullTime{{t1, true}, {t2, true}, {t3, true}}},
-	}
-
-	// Write rows into table first.
-	var muts []*Mutation
-	for i, test := range tests {
-		muts = append(muts, InsertOrUpdate("Types", []string{"RowID", test.col}, []interface{}{i, test.val}))
-	}
-	if _, err := client.Apply(ctx, muts, ApplyAtLeastOnce()); err != nil {
-		t.Fatal(err)
-	}
-
-	for i, test := range tests {
-		row, err := client.Single().ReadRow(ctx, "Types", []interface{}{i}, []string{test.col})
-		if err != nil {
-			t.Fatalf("Unable to fetch row %v: %v", i, err)
-		}
-		// Create new instance of type of test.want.
-		want := test.want
-		if want == nil {
-			want = test.val
-		}
-		gotp := reflect.New(reflect.TypeOf(want))
-		if err := row.Column(0, gotp.Interface()); err != nil {
-			t.Errorf("%d: col:%v val:%#v, %v", i, test.col, test.val, err)
-			continue
-		}
-		got := reflect.Indirect(gotp).Interface()
-
-		// One of the test cases is checking NaN handling.  Given
-		// NaN!=NaN, we can't use reflect to test for it.
-		isNaN := func(t interface{}) bool {
-			f, ok := t.(float64)
-			if !ok {
-				return false
-			}
-			return math.IsNaN(f)
-		}
-		if isNaN(got) && isNaN(want) {
-			continue
-		}
-
-		// Check non-NaN cases.
-		if !reflect.DeepEqual(got, want) {
-			t.Errorf("%d: col:%v val:%#v, got %#v, want %#v", i, test.col, test.val, got, want)
-			continue
-		}
-	}
-}
-
-// Test decoding Cloud Spanner STRUCT type.
-func TestStructTypes(t *testing.T) {
-	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
-	defer cancel()
-	if err := prepare(ctx, t, singerDBStatements); err != nil {
-		tearDown(ctx, t)
-		t.Fatalf("cannot set up testing environment: %v", err)
-	}
-	defer tearDown(ctx, t)
-
-	tests := []struct {
-		q    Statement
-		want func(r *Row) error
-	}{
-		{
-			q: Statement{SQL: `SELECT ARRAY(SELECT STRUCT(1, 2))`},
-			want: func(r *Row) error {
-				// Test STRUCT ARRAY decoding to []NullRow.
-				var rows []NullRow
-				if err := r.Column(0, &rows); err != nil {
-					return err
-				}
-				if len(rows) != 1 {
-					return fmt.Errorf("len(rows) = %d; want 1", len(rows))
-				}
-				if !rows[0].Valid {
-					return fmt.Errorf("rows[0] is NULL")
-				}
-				var i, j int64
-				if err := rows[0].Row.Columns(&i, &j); err != nil {
-					return err
-				}
-				if i != 1 || j != 2 {
-					return fmt.Errorf("got (%d,%d), want (1,2)", i, j)
-				}
-				return nil
-			},
-		},
-		{
-			q: Statement{SQL: `SELECT ARRAY(SELECT STRUCT(1 as foo, 2 as bar)) as col1`},
-			want: func(r *Row) error {
-				// Test Row.ToStruct.
-				s := struct {
-					Col1 []*struct {
-						Foo int64 `spanner:"foo"`
-						Bar int64 `spanner:"bar"`
-					} `spanner:"col1"`
-				}{}
-				if err := r.ToStruct(&s); err != nil {
-					return err
-				}
-				want := struct {
-					Col1 []*struct {
-						Foo int64 `spanner:"foo"`
-						Bar int64 `spanner:"bar"`
-					} `spanner:"col1"`
-				}{
-					Col1: []*struct {
-						Foo int64 `spanner:"foo"`
-						Bar int64 `spanner:"bar"`
-					}{
-						{
-							Foo: 1,
-							Bar: 2,
-						},
-					},
-				}
-				if !reflect.DeepEqual(want, s) {
-					return fmt.Errorf("unexpected decoding result: %v, want %v", s, want)
-				}
-				return nil
-			},
-		},
-	}
-	for i, test := range tests {
-		iter := client.Single().Query(ctx, test.q)
-		defer iter.Stop()
-		row, err := iter.Next()
-		if err != nil {
-			t.Errorf("%d: %v", i, err)
-			continue
-		}
-		if err := test.want(row); err != nil {
-			t.Errorf("%d: %v", i, err)
-			continue
-		}
-	}
-}
-
-func rowToValues(r *Row) ([]interface{}, error) {
-	var x int64
-	var y, z string
-	if err := r.Column(0, &x); err != nil {
-		return nil, err
-	}
-	if err := r.Column(1, &y); err != nil {
-		return nil, err
-	}
-	if err := r.Column(2, &z); err != nil {
-		return nil, err
-	}
-	return []interface{}{x, y, z}, nil
-}
-
-func readAll(iter *RowIterator) ([][]interface{}, error) {
-	defer iter.Stop()
-	var vals [][]interface{}
-	for {
-		row, err := iter.Next()
-		if err == iterator.Done {
-			return vals, nil
-		}
-		if err != nil {
-			return nil, err
-		}
-		v, err := rowToValues(row)
-		if err != nil {
-			return nil, err
-		}
-		vals = append(vals, v)
-	}
-}
-
-func readAllTestTable(iter *RowIterator) ([]testTableRow, error) {
-	defer iter.Stop()
-	var vals []testTableRow
-	for {
-		row, err := iter.Next()
-		if err == iterator.Done {
-			return vals, nil
-		}
-		if err != nil {
-			return nil, err
-		}
-		var ttr testTableRow
-		if err := row.ToStruct(&ttr); err != nil {
-			return nil, err
-		}
-		vals = append(vals, ttr)
-	}
-}
diff --git a/vendor/cloud.google.com/go/spanner/statement.go b/vendor/cloud.google.com/go/spanner/statement.go
deleted file mode 100644
index 8e422b09c..000000000
--- a/vendor/cloud.google.com/go/spanner/statement.go
+++ /dev/null
@@ -1,78 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"fmt"
-
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-	"google.golang.org/grpc/codes"
-)
-
-// A Statement is a SQL query with named parameters.
-//
-// A parameter placeholder consists of '@' followed by the parameter name.
-// Parameter names consist of any combination of letters, numbers, and
-// underscores. Names may be entirely numeric (e.g., "WHERE m.id = @5").
-// Parameters may appear anywhere that a literal value is expected. The same
-// parameter name may be used more than once.  It is an error to execute a
-// statement with unbound parameters. On the other hand, it is allowable to
-// bind parameter names that are not used.
-//
-// See the documentation of the Row type for how Go types are mapped to Cloud
-// Spanner types.
-type Statement struct {
-	SQL    string
-	Params map[string]interface{}
-}
-
-// NewStatement returns a Statement with the given SQL and an empty Params map.
-func NewStatement(sql string) Statement {
-	return Statement{SQL: sql, Params: map[string]interface{}{}}
-}
-
-// errBindParam returns error for not being able to bind parameter to query request.
-func errBindParam(k string, v interface{}, err error) error {
-	if err == nil {
-		return nil
-	}
-	se, ok := toSpannerError(err).(*Error)
-	if !ok {
-		return spannerErrorf(codes.InvalidArgument, "failed to bind query parameter(name: %q, value: %q), error = <%v>", k, v, err)
-	}
-	se.decorate(fmt.Sprintf("failed to bind query parameter(name: %q, value: %q)", k, v))
-	return se
-}
-
-// bindParams binds parameters in a Statement to a sppb.ExecuteSqlRequest.
-func (s *Statement) bindParams(r *sppb.ExecuteSqlRequest) error {
-	r.Params = &proto3.Struct{
-		Fields: map[string]*proto3.Value{},
-	}
-	r.ParamTypes = map[string]*sppb.Type{}
-	for k, v := range s.Params {
-		val, t, err := encodeValue(v)
-		if err != nil {
-			return errBindParam(k, v, err)
-		}
-		r.Params.Fields[k] = val
-		r.ParamTypes[k] = t
-	}
-	return nil
-}
diff --git a/vendor/cloud.google.com/go/spanner/statement_test.go b/vendor/cloud.google.com/go/spanner/statement_test.go
deleted file mode 100644
index a441e0e82..000000000
--- a/vendor/cloud.google.com/go/spanner/statement_test.go
+++ /dev/null
@@ -1,64 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"reflect"
-	"testing"
-
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-)
-
-// Test Statement.bindParams.
-func TestBindParams(t *testing.T) {
-	// Verify Statement.bindParams generates correct values and types.
-	want := sppb.ExecuteSqlRequest{
-		Params: &proto3.Struct{
-			Fields: map[string]*proto3.Value{
-				"var1": stringProto("abc"),
-				"var2": intProto(1),
-			},
-		},
-		ParamTypes: map[string]*sppb.Type{
-			"var1": stringType(),
-			"var2": intType(),
-		},
-	}
-	st := Statement{
-		SQL:    "SELECT id from t_foo WHERE col1 = @var1 AND col2 = @var2",
-		Params: map[string]interface{}{"var1": "abc", "var2": int64(1)},
-	}
-	got := sppb.ExecuteSqlRequest{}
-	if err := st.bindParams(&got); err != nil || !reflect.DeepEqual(got, want) {
-		t.Errorf("bind result: \n(%v, %v)\nwant\n(%v, %v)\n", got, err, want, nil)
-	}
-	// Verify type error reporting.
-	st.Params["var2"] = struct{}{}
-	wantErr := errBindParam("var2", struct{}{}, errEncoderUnsupportedType(struct{}{}))
-	if err := st.bindParams(&got); !reflect.DeepEqual(err, wantErr) {
-		t.Errorf("got unexpected error: %v, want: %v", err, wantErr)
-	}
-}
-
-func TestNewStatement(t *testing.T) {
-	s := NewStatement("query")
-	if got, want := s.SQL, "query"; got != want {
-		t.Errorf("got %q, want %q", got, want)
-	}
-}
diff --git a/vendor/cloud.google.com/go/spanner/timestampbound.go b/vendor/cloud.google.com/go/spanner/timestampbound.go
deleted file mode 100644
index 068d96600..000000000
--- a/vendor/cloud.google.com/go/spanner/timestampbound.go
+++ /dev/null
@@ -1,245 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"fmt"
-	"time"
-
-	pbd "github.com/golang/protobuf/ptypes/duration"
-	pbt "github.com/golang/protobuf/ptypes/timestamp"
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-)
-
-// timestampBoundType specifies the timestamp bound mode.
-type timestampBoundType int
-
-const (
-	strong           timestampBoundType = iota // strong reads
-	exactStaleness                             // read with exact staleness
-	maxStaleness                               // read with max staleness
-	minReadTimestamp                           // read with min freshness
-	readTimestamp                              // read data at exact timestamp
-)
-
-// TimestampBound defines how Cloud Spanner will choose a timestamp for a single
-// read/query or read-only transaction.
-//
-// The types of timestamp bound are:
-//
-//	- Strong (the default).
-//	- Bounded staleness.
-//	- Exact staleness.
-//
-// If the Cloud Spanner database to be read is geographically distributed, stale
-// read-only transactions can execute more quickly than strong or read-write
-// transactions, because they are able to execute far from the leader replica.
-//
-// Each type of timestamp bound is discussed in detail below.  A TimestampBound
-// can be specified when creating transactions, see the documentation of
-// spanner.Client for an example.
-//
-// Strong reads
-//
-// Strong reads are guaranteed to see the effects of all transactions that have
-// committed before the start of the read. Furthermore, all rows yielded by a
-// single read are consistent with each other - if any part of the read
-// observes a transaction, all parts of the read see the transaction.
-//
-// Strong reads are not repeatable: two consecutive strong read-only
-// transactions might return inconsistent results if there are concurrent
-// writes. If consistency across reads is required, the reads should be
-// executed within a transaction or at an exact read timestamp.
-//
-// Use StrongRead() to create a bound of this type.
-//
-// Exact staleness
-//
-// These timestamp bounds execute reads at a user-specified timestamp. Reads at
-// a timestamp are guaranteed to see a consistent prefix of the global
-// transaction history: they observe modifications done by all transactions
-// with a commit timestamp less than or equal to the read timestamp, and
-// observe none of the modifications done by transactions with a larger commit
-// timestamp. They will block until all conflicting transactions that may be
-// assigned commit timestamps less than or equal to the read timestamp have
-// finished.
-//
-// The timestamp can either be expressed as an absolute Cloud Spanner commit
-// timestamp or a staleness relative to the current time.
-//
-// These modes do not require a "negotiation phase" to pick a timestamp. As a
-// result, they execute slightly faster than the equivalent boundedly stale
-// concurrency modes. On the other hand, boundedly stale reads usually return
-// fresher results.
-//
-// Use ReadTimestamp() and ExactStaleness() to create a bound of this type.
-//
-// Bounded staleness
-//
-// Bounded staleness modes allow Cloud Spanner to pick the read timestamp, subject to
-// a user-provided staleness bound. Cloud Spanner chooses the newest timestamp within
-// the staleness bound that allows execution of the reads at the closest
-// available replica without blocking.
-//
-// All rows yielded are consistent with each other -- if any part of the read
-// observes a transaction, all parts of the read see the transaction. Boundedly
-// stale reads are not repeatable: two stale reads, even if they use the same
-// staleness bound, can execute at different timestamps and thus return
-// inconsistent results.
-//
-// Boundedly stale reads execute in two phases: the first phase negotiates a
-// timestamp among all replicas needed to serve the read. In the second phase,
-// reads are executed at the negotiated timestamp.
-//
-// As a result of the two phase execution, bounded staleness reads are usually
-// a little slower than comparable exact staleness reads. However, they are
-// typically able to return fresher results, and are more likely to execute at
-// the closest replica.
-//
-// Because the timestamp negotiation requires up-front knowledge of which rows
-// will be read, it can only be used with single-use reads and single-use
-// read-only transactions.
-//
-// Use MinReadTimestamp() and MaxStaleness() to create a bound of this type.
-//
-// Old read timestamps and garbage collection
-//
-// Cloud Spanner continuously garbage collects deleted and overwritten data in the
-// background to reclaim storage space. This process is known as "version
-// GC". By default, version GC reclaims versions after they are four hours
-// old. Because of this, Cloud Spanner cannot perform reads at read timestamps more
-// than four hours in the past. This restriction also applies to in-progress
-// reads and/or SQL queries whose timestamp become too old while
-// executing. Reads and SQL queries with too-old read timestamps fail with the
-// error ErrorCode.FAILED_PRECONDITION.
-type TimestampBound struct {
-	mode timestampBoundType
-	d    time.Duration
-	t    time.Time
-}
-
-// StrongRead returns a TimestampBound that will perform reads and queries at a
-// timestamp where all previously committed transactions are visible.
-func StrongRead() TimestampBound {
-	return TimestampBound{mode: strong}
-}
-
-// ExactStaleness returns a TimestampBound that will perform reads and queries
-// at an exact staleness.
-func ExactStaleness(d time.Duration) TimestampBound {
-	return TimestampBound{
-		mode: exactStaleness,
-		d:    d,
-	}
-}
-
-// MaxStaleness returns a TimestampBound that will perform reads and queries at
-// a time chosen to be at most "d" stale.
-func MaxStaleness(d time.Duration) TimestampBound {
-	return TimestampBound{
-		mode: maxStaleness,
-		d:    d,
-	}
-}
-
-// MinReadTimestamp returns a TimestampBound that bound that will perform reads
-// and queries at a time chosen to be at least "t".
-func MinReadTimestamp(t time.Time) TimestampBound {
-	return TimestampBound{
-		mode: minReadTimestamp,
-		t:    t,
-	}
-}
-
-// ReadTimestamp returns a TimestampBound that will peform reads and queries at
-// the given time.
-func ReadTimestamp(t time.Time) TimestampBound {
-	return TimestampBound{
-		mode: readTimestamp,
-		t:    t,
-	}
-}
-
-// String implements fmt.Stringer.
-func (tb TimestampBound) String() string {
-	switch tb.mode {
-	case strong:
-		return fmt.Sprintf("(strong)")
-	case exactStaleness:
-		return fmt.Sprintf("(exactStaleness: %s)", tb.d)
-	case maxStaleness:
-		return fmt.Sprintf("(maxStaleness: %s)", tb.d)
-	case minReadTimestamp:
-		return fmt.Sprintf("(minReadTimestamp: %s)", tb.t)
-	case readTimestamp:
-		return fmt.Sprintf("(readTimestamp: %s)", tb.t)
-	default:
-		return fmt.Sprintf("{mode=%v, d=%v, t=%v}", tb.mode, tb.d, tb.t)
-	}
-}
-
-// durationProto takes a time.Duration and converts it into pdb.Duration for
-// calling gRPC APIs.
-func durationProto(d time.Duration) *pbd.Duration {
-	n := d.Nanoseconds()
-	return &pbd.Duration{
-		Seconds: n / int64(time.Second),
-		Nanos:   int32(n % int64(time.Second)),
-	}
-}
-
-// timestampProto takes a time.Time and converts it into pbt.Timestamp for calling
-// gRPC APIs.
-func timestampProto(t time.Time) *pbt.Timestamp {
-	return &pbt.Timestamp{
-		Seconds: t.Unix(),
-		Nanos:   int32(t.Nanosecond()),
-	}
-}
-
-// buildTransactionOptionsReadOnly converts a spanner.TimestampBound into a sppb.TransactionOptions_ReadOnly
-// transaction option, which is then used in transactional reads.
-func buildTransactionOptionsReadOnly(tb TimestampBound, returnReadTimestamp bool) *sppb.TransactionOptions_ReadOnly {
-	pb := &sppb.TransactionOptions_ReadOnly{
-		ReturnReadTimestamp: returnReadTimestamp,
-	}
-	switch tb.mode {
-	case strong:
-		pb.TimestampBound = &sppb.TransactionOptions_ReadOnly_Strong{
-			Strong: true,
-		}
-	case exactStaleness:
-		pb.TimestampBound = &sppb.TransactionOptions_ReadOnly_ExactStaleness{
-			ExactStaleness: durationProto(tb.d),
-		}
-	case maxStaleness:
-		pb.TimestampBound = &sppb.TransactionOptions_ReadOnly_MaxStaleness{
-			MaxStaleness: durationProto(tb.d),
-		}
-	case minReadTimestamp:
-		pb.TimestampBound = &sppb.TransactionOptions_ReadOnly_MinReadTimestamp{
-			MinReadTimestamp: timestampProto(tb.t),
-		}
-	case readTimestamp:
-		pb.TimestampBound = &sppb.TransactionOptions_ReadOnly_ReadTimestamp{
-			ReadTimestamp: timestampProto(tb.t),
-		}
-	default:
-		panic(fmt.Sprintf("buildTransactionOptionsReadOnly(%v,%v)", tb, returnReadTimestamp))
-	}
-	return pb
-}
diff --git a/vendor/cloud.google.com/go/spanner/timestampbound_test.go b/vendor/cloud.google.com/go/spanner/timestampbound_test.go
deleted file mode 100644
index 47fb481db..000000000
--- a/vendor/cloud.google.com/go/spanner/timestampbound_test.go
+++ /dev/null
@@ -1,208 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"reflect"
-	"testing"
-	"time"
-
-	pbd "github.com/golang/protobuf/ptypes/duration"
-	pbt "github.com/golang/protobuf/ptypes/timestamp"
-
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-)
-
-// Test generating TimestampBound for strong reads.
-func TestStrong(t *testing.T) {
-	got := StrongRead()
-	want := TimestampBound{mode: strong}
-	if !reflect.DeepEqual(got, want) {
-		t.Errorf("Strong() = %v; want %v", got, want)
-	}
-}
-
-// Test generating TimestampBound for reads with exact staleness.
-func TestExactStaleness(t *testing.T) {
-	got := ExactStaleness(10 * time.Second)
-	want := TimestampBound{mode: exactStaleness, d: 10 * time.Second}
-	if !reflect.DeepEqual(got, want) {
-		t.Errorf("ExactStaleness(10*time.Second) = %v; want %v", got, want)
-	}
-}
-
-// Test generating TimestampBound for reads with max staleness.
-func TestMaxStaleness(t *testing.T) {
-	got := MaxStaleness(10 * time.Second)
-	want := TimestampBound{mode: maxStaleness, d: 10 * time.Second}
-	if !reflect.DeepEqual(got, want) {
-		t.Errorf("MaxStaleness(10*time.Second) = %v; want %v", got, want)
-	}
-}
-
-// Test generating TimestampBound for reads with minimum freshness requirement.
-func TestMinReadTimestamp(t *testing.T) {
-	ts := time.Now()
-	got := MinReadTimestamp(ts)
-	want := TimestampBound{mode: minReadTimestamp, t: ts}
-	if !reflect.DeepEqual(got, want) {
-		t.Errorf("MinReadTimestamp(%v) = %v; want %v", ts, got, want)
-	}
-}
-
-// Test generating TimestampBound for reads requesting data at a exact timestamp.
-func TestReadTimestamp(t *testing.T) {
-	ts := time.Now()
-	got := ReadTimestamp(ts)
-	want := TimestampBound{mode: readTimestamp, t: ts}
-	if !reflect.DeepEqual(got, want) {
-		t.Errorf("ReadTimestamp(%v) = %v; want %v", ts, got, want)
-	}
-}
-
-// Test TimestampBound.String.
-func TestTimestampBoundString(t *testing.T) {
-	ts := time.Unix(1136239445, 0).UTC()
-	var tests = []struct {
-		tb   TimestampBound
-		want string
-	}{
-		{
-			tb:   TimestampBound{mode: strong},
-			want: "(strong)",
-		},
-		{
-			tb:   TimestampBound{mode: exactStaleness, d: 10 * time.Second},
-			want: "(exactStaleness: 10s)",
-		},
-		{
-			tb:   TimestampBound{mode: maxStaleness, d: 10 * time.Second},
-			want: "(maxStaleness: 10s)",
-		},
-		{
-			tb:   TimestampBound{mode: minReadTimestamp, t: ts},
-			want: "(minReadTimestamp: 2006-01-02 22:04:05 +0000 UTC)",
-		},
-		{
-			tb:   TimestampBound{mode: readTimestamp, t: ts},
-			want: "(readTimestamp: 2006-01-02 22:04:05 +0000 UTC)",
-		},
-	}
-	for _, test := range tests {
-		got := test.tb.String()
-		if got != test.want {
-			t.Errorf("%#v.String():\ngot  %q\nwant %q", test.tb, got, test.want)
-		}
-	}
-}
-
-// Test time.Duration to pdb.Duration conversion.
-func TestDurationProto(t *testing.T) {
-	var tests = []struct {
-		d    time.Duration
-		want pbd.Duration
-	}{
-		{time.Duration(0), pbd.Duration{Seconds: 0, Nanos: 0}},
-		{time.Second, pbd.Duration{Seconds: 1, Nanos: 0}},
-		{time.Millisecond, pbd.Duration{Seconds: 0, Nanos: 1e6}},
-		{15 * time.Nanosecond, pbd.Duration{Seconds: 0, Nanos: 15}},
-		{42 * time.Hour, pbd.Duration{Seconds: 151200}},
-		{-(1*time.Hour + 4*time.Millisecond), pbd.Duration{Seconds: -3600, Nanos: -4e6}},
-	}
-	for _, test := range tests {
-		got := durationProto(test.d)
-		if !reflect.DeepEqual(got, &test.want) {
-			t.Errorf("durationProto(%v) = %v; want %v", test.d, got, test.want)
-		}
-	}
-}
-
-// Test time.Time to pbt.Timestamp conversion.
-func TestTimeProto(t *testing.T) {
-	var tests = []struct {
-		t    time.Time
-		want pbt.Timestamp
-	}{
-		{time.Unix(0, 0), pbt.Timestamp{}},
-		{time.Unix(1136239445, 12345), pbt.Timestamp{Seconds: 1136239445, Nanos: 12345}},
-		{time.Unix(-1000, 12345), pbt.Timestamp{Seconds: -1000, Nanos: 12345}},
-	}
-	for _, test := range tests {
-		got := timestampProto(test.t)
-		if !reflect.DeepEqual(got, &test.want) {
-			t.Errorf("timestampProto(%v) = %v; want %v", test.t, got, test.want)
-		}
-	}
-}
-
-// Test readonly transaction option builder.
-func TestBuildTransactionOptionsReadOnly(t *testing.T) {
-	ts := time.Unix(1136239445, 12345)
-	var tests = []struct {
-		tb   TimestampBound
-		ts   bool
-		want sppb.TransactionOptions_ReadOnly
-	}{
-		{
-			StrongRead(), false,
-			sppb.TransactionOptions_ReadOnly{
-				TimestampBound: &sppb.TransactionOptions_ReadOnly_Strong{
-					Strong: true},
-				ReturnReadTimestamp: false,
-			},
-		},
-		{
-			ExactStaleness(10 * time.Second), true,
-			sppb.TransactionOptions_ReadOnly{
-				TimestampBound: &sppb.TransactionOptions_ReadOnly_ExactStaleness{
-					ExactStaleness: &pbd.Duration{Seconds: 10}},
-				ReturnReadTimestamp: true,
-			},
-		},
-		{
-			MaxStaleness(10 * time.Second), true,
-			sppb.TransactionOptions_ReadOnly{
-				TimestampBound: &sppb.TransactionOptions_ReadOnly_MaxStaleness{
-					MaxStaleness: &pbd.Duration{Seconds: 10}},
-				ReturnReadTimestamp: true,
-			},
-		},
-
-		{
-			MinReadTimestamp(ts), true,
-			sppb.TransactionOptions_ReadOnly{
-				TimestampBound: &sppb.TransactionOptions_ReadOnly_MinReadTimestamp{
-					MinReadTimestamp: &pbt.Timestamp{Seconds: 1136239445, Nanos: 12345}},
-				ReturnReadTimestamp: true,
-			},
-		},
-		{
-			ReadTimestamp(ts), true,
-			sppb.TransactionOptions_ReadOnly{
-				TimestampBound: &sppb.TransactionOptions_ReadOnly_ReadTimestamp{
-					ReadTimestamp: &pbt.Timestamp{Seconds: 1136239445, Nanos: 12345}},
-				ReturnReadTimestamp: true,
-			},
-		},
-	}
-	for _, test := range tests {
-		got := buildTransactionOptionsReadOnly(test.tb, test.ts)
-		if !reflect.DeepEqual(got, &test.want) {
-			t.Errorf("buildTransactionOptionsReadOnly(%v,%v) = %v; want %v", test.tb, test.ts, got, test.want)
-		}
-	}
-}
diff --git a/vendor/cloud.google.com/go/spanner/transaction.go b/vendor/cloud.google.com/go/spanner/transaction.go
deleted file mode 100644
index ff1e96fe9..000000000
--- a/vendor/cloud.google.com/go/spanner/transaction.go
+++ /dev/null
@@ -1,821 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"sync"
-	"time"
-
-	"golang.org/x/net/context"
-
-	"google.golang.org/api/iterator"
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/metadata"
-)
-
-// transactionID stores a transaction ID which uniquely identifies a transaction in Cloud Spanner.
-type transactionID []byte
-
-// txReadEnv manages a read-transaction environment consisting of a session handle and a transaction selector.
-type txReadEnv interface {
-	// acquire returns a read-transaction environment that can be used to perform a transactional read.
-	acquire(ctx context.Context) (*sessionHandle, *sppb.TransactionSelector, error)
-	// sets the transaction's read timestamp
-	setTimestamp(time.Time)
-	// release should be called at the end of every transactional read to deal with session recycling.
-	release(error)
-}
-
-// txReadOnly contains methods for doing transactional reads.
-type txReadOnly struct {
-	// read-transaction environment for performing transactional read operations.
-	txReadEnv
-}
-
-// errSessionClosed returns error for using a recycled/destroyed session
-func errSessionClosed(sh *sessionHandle) error {
-	return spannerErrorf(codes.FailedPrecondition,
-		"session is already recycled / destroyed: session_id = %q, rpc_client = %v", sh.getID(), sh.getClient())
-}
-
-// Read returns a RowIterator for reading multiple rows from the database.
-func (t *txReadOnly) Read(ctx context.Context, table string, keys KeySet, columns []string) *RowIterator {
-	// ReadUsingIndex will use primary index if an empty index name is provided.
-	return t.ReadUsingIndex(ctx, table, "", keys, columns)
-}
-
-// ReadUsingIndex returns a RowIterator for reading multiple rows from the database
-// using an index.
-//
-// Currently, this function can only read columns that are part of the index
-// key, part of the primary key, or stored in the index due to a STORING clause
-// in the index definition.
-func (t *txReadOnly) ReadUsingIndex(ctx context.Context, table, index string, keys KeySet, columns []string) *RowIterator {
-	var (
-		sh  *sessionHandle
-		ts  *sppb.TransactionSelector
-		err error
-	)
-	kset, err := keys.keySetProto()
-	if err != nil {
-		return &RowIterator{err: err}
-	}
-	if sh, ts, err = t.acquire(ctx); err != nil {
-		return &RowIterator{err: err}
-	}
-	// Cloud Spanner will return "Session not found" on bad sessions.
-	sid, client := sh.getID(), sh.getClient()
-	if sid == "" || client == nil {
-		// Might happen if transaction is closed in the middle of a API call.
-		return &RowIterator{err: errSessionClosed(sh)}
-	}
-	return stream(
-		contextWithOutgoingMetadata(ctx, sh.getMetadata()),
-		func(ctx context.Context, resumeToken []byte) (streamingReceiver, error) {
-			return client.StreamingRead(ctx,
-				&sppb.ReadRequest{
-					Session:     sid,
-					Transaction: ts,
-					Table:       table,
-					Index:       index,
-					Columns:     columns,
-					KeySet:      kset,
-					ResumeToken: resumeToken,
-				})
-		},
-		t.setTimestamp,
-		t.release,
-	)
-}
-
-// errRowNotFound returns error for not being able to read the row identified by key.
-func errRowNotFound(table string, key Key) error {
-	return spannerErrorf(codes.NotFound, "row not found(Table: %v, PrimaryKey: %v)", table, key)
-}
-
-// ReadRow reads a single row from the database.
-//
-// If no row is present with the given key, then ReadRow returns an error where
-// spanner.ErrCode(err) is codes.NotFound.
-func (t *txReadOnly) ReadRow(ctx context.Context, table string, key Key, columns []string) (*Row, error) {
-	iter := t.Read(ctx, table, key, columns)
-	defer iter.Stop()
-	row, err := iter.Next()
-	switch err {
-	case iterator.Done:
-		return nil, errRowNotFound(table, key)
-	case nil:
-		return row, nil
-	default:
-		return nil, err
-	}
-}
-
-// Query executes a query against the database. It returns a RowIterator
-// for retrieving the resulting rows.
-func (t *txReadOnly) Query(ctx context.Context, statement Statement) *RowIterator {
-	var (
-		sh  *sessionHandle
-		ts  *sppb.TransactionSelector
-		err error
-	)
-	if sh, ts, err = t.acquire(ctx); err != nil {
-		return &RowIterator{err: err}
-	}
-	// Cloud Spanner will return "Session not found" on bad sessions.
-	sid, client := sh.getID(), sh.getClient()
-	if sid == "" || client == nil {
-		// Might happen if transaction is closed in the middle of a API call.
-		return &RowIterator{err: errSessionClosed(sh)}
-	}
-	req := &sppb.ExecuteSqlRequest{
-		Session:     sid,
-		Transaction: ts,
-		Sql:         statement.SQL,
-	}
-	if err := statement.bindParams(req); err != nil {
-		return &RowIterator{err: err}
-	}
-	return stream(
-		contextWithOutgoingMetadata(ctx, sh.getMetadata()),
-		func(ctx context.Context, resumeToken []byte) (streamingReceiver, error) {
-			req.ResumeToken = resumeToken
-			return client.ExecuteStreamingSql(ctx, req)
-		},
-		t.setTimestamp,
-		t.release)
-}
-
-// txState is the status of a transaction.
-type txState int
-
-const (
-	// transaction is new, waiting to be initialized.
-	txNew txState = iota
-	// transaction is being initialized.
-	txInit
-	// transaction is active and can perform read/write.
-	txActive
-	// transaction is closed, cannot be used anymore.
-	txClosed
-)
-
-// errRtsUnavailable returns error for read transaction's read timestamp being unavailable.
-func errRtsUnavailable() error {
-	return spannerErrorf(codes.Internal, "read timestamp is unavailable")
-}
-
-// errTxNotInitialized returns error for using an uninitialized transaction.
-func errTxNotInitialized() error {
-	return spannerErrorf(codes.InvalidArgument, "cannot use a uninitialized transaction")
-}
-
-// errTxClosed returns error for using a closed transaction.
-func errTxClosed() error {
-	return spannerErrorf(codes.InvalidArgument, "cannot use a closed transaction")
-}
-
-// errUnexpectedTxState returns error for transaction enters an unexpected state.
-func errUnexpectedTxState(ts txState) error {
-	return spannerErrorf(codes.FailedPrecondition, "unexpected transaction state: %v", ts)
-}
-
-// ReadOnlyTransaction provides a snapshot transaction with guaranteed
-// consistency across reads, but does not allow writes.  Read-only
-// transactions can be configured to read at timestamps in the past.
-//
-// Read-only transactions do not take locks. Instead, they work by choosing a
-// Cloud Spanner timestamp, then executing all reads at that timestamp. Since they do
-// not acquire locks, they do not block concurrent read-write transactions.
-//
-// Unlike locking read-write transactions, read-only transactions never
-// abort. They can fail if the chosen read timestamp is garbage collected;
-// however, the default garbage collection policy is generous enough that most
-// applications do not need to worry about this in practice. See the
-// documentation of TimestampBound for more details.
-//
-// A ReadOnlyTransaction consumes resources on the server until Close() is
-// called.
-type ReadOnlyTransaction struct {
-	// txReadOnly contains methods for performing transactional reads.
-	txReadOnly
-
-	// singleUse indicates that the transaction can be used for only one read.
-	singleUse bool
-
-	// sp is the session pool for allocating a session to execute the read-only transaction. It is set only once during initialization of the ReadOnlyTransaction.
-	sp *sessionPool
-	// mu protects concurrent access to the internal states of ReadOnlyTransaction.
-	mu sync.Mutex
-	// tx is the transaction ID in Cloud Spanner that uniquely identifies the ReadOnlyTransaction.
-	tx transactionID
-	// txReadyOrClosed is for broadcasting that transaction ID has been returned by Cloud Spanner or that transaction is closed.
-	txReadyOrClosed chan struct{}
-	// state is the current transaction status of the ReadOnly transaction.
-	state txState
-	// sh is the sessionHandle allocated from sp.
-	sh *sessionHandle
-	// rts is the read timestamp returned by transactional reads.
-	rts time.Time
-	// tb is the read staleness bound specification for transactional reads.
-	tb TimestampBound
-}
-
-// errTxInitTimeout returns error for timeout in waiting for initialization of the transaction.
-func errTxInitTimeout() error {
-	return spannerErrorf(codes.Canceled, "timeout/context canceled in waiting for transaction's initialization")
-}
-
-// getTimestampBound returns the read staleness bound specified for the ReadOnlyTransaction.
-func (t *ReadOnlyTransaction) getTimestampBound() TimestampBound {
-	t.mu.Lock()
-	defer t.mu.Unlock()
-	return t.tb
-}
-
-// begin starts a snapshot read-only Transaction on Cloud Spanner.
-func (t *ReadOnlyTransaction) begin(ctx context.Context) error {
-	var (
-		locked bool
-		tx     transactionID
-		rts    time.Time
-		sh     *sessionHandle
-		err    error
-	)
-	defer func() {
-		if !locked {
-			t.mu.Lock()
-			// Not necessary, just to make it clear that t.mu is being held when locked == true.
-			locked = true
-		}
-		if t.state != txClosed {
-			// Signal other initialization routines.
-			close(t.txReadyOrClosed)
-			t.txReadyOrClosed = make(chan struct{})
-		}
-		t.mu.Unlock()
-		if err != nil && sh != nil {
-			// Got a valid session handle, but failed to initalize transaction on Cloud Spanner.
-			if shouldDropSession(err) {
-				sh.destroy()
-			}
-			// If sh.destroy was already executed, this becomes a noop.
-			sh.recycle()
-		}
-	}()
-	sh, err = t.sp.take(ctx)
-	if err != nil {
-		return err
-	}
-	err = runRetryable(contextWithOutgoingMetadata(ctx, sh.getMetadata()), func(ctx context.Context) error {
-		res, e := sh.getClient().BeginTransaction(ctx, &sppb.BeginTransactionRequest{
-			Session: sh.getID(),
-			Options: &sppb.TransactionOptions{
-				Mode: &sppb.TransactionOptions_ReadOnly_{
-					ReadOnly: buildTransactionOptionsReadOnly(t.getTimestampBound(), true),
-				},
-			},
-		})
-		if e != nil {
-			return e
-		}
-		tx = res.Id
-		if res.ReadTimestamp != nil {
-			rts = time.Unix(res.ReadTimestamp.Seconds, int64(res.ReadTimestamp.Nanos))
-		}
-		return nil
-	})
-	t.mu.Lock()
-	locked = true            // defer function will be executed with t.mu being held.
-	if t.state == txClosed { // During the execution of t.begin(), t.Close() was invoked.
-		return errSessionClosed(sh)
-	}
-	// If begin() fails, this allows other queries to take over the initialization.
-	t.tx = nil
-	if err == nil {
-		t.tx = tx
-		t.rts = rts
-		t.sh = sh
-		// State transite to txActive.
-		t.state = txActive
-	}
-	return err
-}
-
-// acquire implements txReadEnv.acquire.
-func (t *ReadOnlyTransaction) acquire(ctx context.Context) (*sessionHandle, *sppb.TransactionSelector, error) {
-	if err := checkNestedTxn(ctx); err != nil {
-		return nil, nil, err
-	}
-	if t.singleUse {
-		return t.acquireSingleUse(ctx)
-	}
-	return t.acquireMultiUse(ctx)
-}
-
-func (t *ReadOnlyTransaction) acquireSingleUse(ctx context.Context) (*sessionHandle, *sppb.TransactionSelector, error) {
-	t.mu.Lock()
-	defer t.mu.Unlock()
-	switch t.state {
-	case txClosed:
-		// A closed single-use transaction can never be reused.
-		return nil, nil, errTxClosed()
-	case txNew:
-		t.state = txClosed
-		ts := &sppb.TransactionSelector{
-			Selector: &sppb.TransactionSelector_SingleUse{
-				SingleUse: &sppb.TransactionOptions{
-					Mode: &sppb.TransactionOptions_ReadOnly_{
-						ReadOnly: buildTransactionOptionsReadOnly(t.tb, true),
-					},
-				},
-			},
-		}
-		sh, err := t.sp.take(ctx)
-		if err != nil {
-			return nil, nil, err
-		}
-		// Install session handle into t, which can be used for readonly operations later.
-		t.sh = sh
-		return sh, ts, nil
-	}
-	us := t.state
-	// SingleUse transaction should only be in either txNew state or txClosed state.
-	return nil, nil, errUnexpectedTxState(us)
-}
-
-func (t *ReadOnlyTransaction) acquireMultiUse(ctx context.Context) (*sessionHandle, *sppb.TransactionSelector, error) {
-	for {
-		t.mu.Lock()
-		switch t.state {
-		case txClosed:
-			t.mu.Unlock()
-			return nil, nil, errTxClosed()
-		case txNew:
-			// State transit to txInit so that no further TimestampBound change is accepted.
-			t.state = txInit
-			t.mu.Unlock()
-			continue
-		case txInit:
-			if t.tx != nil {
-				// Wait for a transaction ID to become ready.
-				txReadyOrClosed := t.txReadyOrClosed
-				t.mu.Unlock()
-				select {
-				case <-txReadyOrClosed:
-					// Need to check transaction state again.
-					continue
-				case <-ctx.Done():
-					// The waiting for initialization is timeout, return error directly.
-					return nil, nil, errTxInitTimeout()
-				}
-			}
-			// Take the ownership of initializing the transaction.
-			t.tx = transactionID{}
-			t.mu.Unlock()
-			// Begin a read-only transaction.
-			// TODO: consider adding a transaction option which allow queries to initiate transactions by themselves. Note that this option might not be
-			// always good because the ID of the new transaction won't be ready till the query returns some data or completes.
-			if err := t.begin(ctx); err != nil {
-				return nil, nil, err
-			}
-			// If t.begin() succeeded, t.state should have been changed to txActive, so we can just continue here.
-			continue
-		case txActive:
-			sh := t.sh
-			ts := &sppb.TransactionSelector{
-				Selector: &sppb.TransactionSelector_Id{
-					Id: t.tx,
-				},
-			}
-			t.mu.Unlock()
-			return sh, ts, nil
-		}
-		state := t.state
-		t.mu.Unlock()
-		return nil, nil, errUnexpectedTxState(state)
-	}
-}
-
-func (t *ReadOnlyTransaction) setTimestamp(ts time.Time) {
-	t.mu.Lock()
-	defer t.mu.Unlock()
-	if t.rts.IsZero() {
-		t.rts = ts
-	}
-}
-
-// release implements txReadEnv.release.
-func (t *ReadOnlyTransaction) release(err error) {
-	t.mu.Lock()
-	sh := t.sh
-	t.mu.Unlock()
-	if sh != nil { // sh could be nil if t.acquire() fails.
-		if shouldDropSession(err) {
-			sh.destroy()
-		}
-		if t.singleUse {
-			// If session handle is already destroyed, this becomes a noop.
-			sh.recycle()
-		}
-	}
-}
-
-// Close closes a ReadOnlyTransaction, the transaction cannot perform any reads after being closed.
-func (t *ReadOnlyTransaction) Close() {
-	if t.singleUse {
-		return
-	}
-	t.mu.Lock()
-	if t.state != txClosed {
-		t.state = txClosed
-		close(t.txReadyOrClosed)
-	}
-	sh := t.sh
-	t.mu.Unlock()
-	if sh == nil {
-		return
-	}
-	// If session handle is already destroyed, this becomes a noop.
-	// If there are still active queries and if the recycled session is reused before they complete, Cloud Spanner will cancel them
-	// on behalf of the new transaction on the session.
-	if sh != nil {
-		sh.recycle()
-	}
-}
-
-// Timestamp returns the timestamp chosen to perform reads and
-// queries in this transaction. The value can only be read after some
-// read or query has either returned some data or completed without
-// returning any data.
-func (t *ReadOnlyTransaction) Timestamp() (time.Time, error) {
-	t.mu.Lock()
-	defer t.mu.Unlock()
-	if t.rts.IsZero() {
-		return t.rts, errRtsUnavailable()
-	}
-	return t.rts, nil
-}
-
-// WithTimestampBound specifies the TimestampBound to use for read or query.
-// This can only be used before the first read or query is invoked. Note:
-// bounded staleness is not available with general ReadOnlyTransactions; use a
-// single-use ReadOnlyTransaction instead.
-//
-// The returned value is the ReadOnlyTransaction so calls can be chained.
-func (t *ReadOnlyTransaction) WithTimestampBound(tb TimestampBound) *ReadOnlyTransaction {
-	t.mu.Lock()
-	defer t.mu.Unlock()
-	if t.state == txNew {
-		// Only allow to set TimestampBound before the first query.
-		t.tb = tb
-	}
-	return t
-}
-
-// ReadWriteTransaction provides a locking read-write transaction.
-//
-// This type of transaction is the only way to write data into Cloud Spanner;
-// (*Client).Apply and (*Client).ApplyAtLeastOnce use transactions
-// internally. These transactions rely on pessimistic locking and, if
-// necessary, two-phase commit. Locking read-write transactions may abort,
-// requiring the application to retry. However, the interface exposed by
-// (*Client).ReadWriteTransaction eliminates the need for applications to write
-// retry loops explicitly.
-//
-// Locking transactions may be used to atomically read-modify-write data
-// anywhere in a database. This type of transaction is externally consistent.
-//
-// Clients should attempt to minimize the amount of time a transaction is
-// active. Faster transactions commit with higher probability and cause less
-// contention. Cloud Spanner attempts to keep read locks active as long as the
-// transaction continues to do reads.  Long periods of inactivity at the client
-// may cause Cloud Spanner to release a transaction's locks and abort it.
-//
-// Reads performed within a transaction acquire locks on the data being
-// read. Writes can only be done at commit time, after all reads have been
-// completed. Conceptually, a read-write transaction consists of zero or more
-// reads or SQL queries followed by a commit.
-//
-// See (*Client).ReadWriteTransaction for an example.
-//
-// Semantics
-//
-// Cloud Spanner can commit the transaction if all read locks it acquired are still
-// valid at commit time, and it is able to acquire write locks for all
-// writes. Cloud Spanner can abort the transaction for any reason. If a commit
-// attempt returns ABORTED, Cloud Spanner guarantees that the transaction has not
-// modified any user data in Cloud Spanner.
-//
-// Unless the transaction commits, Cloud Spanner makes no guarantees about how long
-// the transaction's locks were held for. It is an error to use Cloud Spanner locks
-// for any sort of mutual exclusion other than between Cloud Spanner transactions
-// themselves.
-//
-// Aborted transactions
-//
-// Application code does not need to retry explicitly; RunInTransaction will
-// automatically retry a transaction if an attempt results in an abort. The
-// lock priority of a transaction increases after each prior aborted
-// transaction, meaning that the next attempt has a slightly better chance of
-// success than before.
-//
-// Under some circumstances (e.g., many transactions attempting to modify the
-// same row(s)), a transaction can abort many times in a short period before
-// successfully committing. Thus, it is not a good idea to cap the number of
-// retries a transaction can attempt; instead, it is better to limit the total
-// amount of wall time spent retrying.
-//
-// Idle transactions
-//
-// A transaction is considered idle if it has no outstanding reads or SQL
-// queries and has not started a read or SQL query within the last 10
-// seconds. Idle transactions can be aborted by Cloud Spanner so that they don't hold
-// on to locks indefinitely. In that case, the commit will fail with error
-// ABORTED.
-//
-// If this behavior is undesirable, periodically executing a simple SQL query
-// in the transaction (e.g., SELECT 1) prevents the transaction from becoming
-// idle.
-type ReadWriteTransaction struct {
-	// txReadOnly contains methods for performing transactional reads.
-	txReadOnly
-	// sh is the sessionHandle allocated from sp. It is set only once during the initialization of ReadWriteTransaction.
-	sh *sessionHandle
-	// tx is the transaction ID in Cloud Spanner that uniquely identifies the ReadWriteTransaction.
-	// It is set only once in ReadWriteTransaction.begin() during the initialization of ReadWriteTransaction.
-	tx transactionID
-	// mu protects concurrent access to the internal states of ReadWriteTransaction.
-	mu sync.Mutex
-	// state is the current transaction status of the read-write transaction.
-	state txState
-	// wb is the set of buffered mutations waiting to be commited.
-	wb []*Mutation
-}
-
-// BufferWrite adds a list of mutations to the set of updates that will be
-// applied when the transaction is committed. It does not actually apply the
-// write until the transaction is committed, so the operation does not
-// block. The effects of the write won't be visible to any reads (including
-// reads done in the same transaction) until the transaction commits.
-//
-// See the example for Client.ReadWriteTransaction.
-func (t *ReadWriteTransaction) BufferWrite(ms []*Mutation) error {
-	t.mu.Lock()
-	defer t.mu.Unlock()
-	if t.state == txClosed {
-		return errTxClosed()
-	}
-	if t.state != txActive {
-		return errUnexpectedTxState(t.state)
-	}
-	t.wb = append(t.wb, ms...)
-	return nil
-}
-
-// acquire implements txReadEnv.acquire.
-func (t *ReadWriteTransaction) acquire(ctx context.Context) (*sessionHandle, *sppb.TransactionSelector, error) {
-	ts := &sppb.TransactionSelector{
-		Selector: &sppb.TransactionSelector_Id{
-			Id: t.tx,
-		},
-	}
-	t.mu.Lock()
-	defer t.mu.Unlock()
-	switch t.state {
-	case txClosed:
-		return nil, nil, errTxClosed()
-	case txActive:
-		return t.sh, ts, nil
-	}
-	return nil, nil, errUnexpectedTxState(t.state)
-}
-
-// release implements txReadEnv.release.
-func (t *ReadWriteTransaction) release(err error) {
-	t.mu.Lock()
-	sh := t.sh
-	t.mu.Unlock()
-	if sh != nil && shouldDropSession(err) {
-		sh.destroy()
-	}
-}
-
-func beginTransaction(ctx context.Context, sid string, client sppb.SpannerClient) (transactionID, error) {
-	var tx transactionID
-	err := runRetryable(ctx, func(ctx context.Context) error {
-		res, e := client.BeginTransaction(ctx, &sppb.BeginTransactionRequest{
-			Session: sid,
-			Options: &sppb.TransactionOptions{
-				Mode: &sppb.TransactionOptions_ReadWrite_{
-					ReadWrite: &sppb.TransactionOptions_ReadWrite{},
-				},
-			},
-		})
-		if e != nil {
-			return e
-		}
-		tx = res.Id
-		return nil
-	})
-	if err != nil {
-		return nil, err
-	}
-	return tx, nil
-}
-
-// begin starts a read-write transacton on Cloud Spanner, it is always called before any of the public APIs.
-func (t *ReadWriteTransaction) begin(ctx context.Context) error {
-	if t.tx != nil {
-		t.state = txActive
-		return nil
-	}
-	tx, err := beginTransaction(contextWithOutgoingMetadata(ctx, t.sh.getMetadata()), t.sh.getID(), t.sh.getClient())
-	if err == nil {
-		t.tx = tx
-		t.state = txActive
-		return nil
-	}
-	if shouldDropSession(err) {
-		t.sh.destroy()
-	}
-	return err
-}
-
-// commit tries to commit a readwrite transaction to Cloud Spanner. It also returns the commit timestamp for the transactions.
-func (t *ReadWriteTransaction) commit(ctx context.Context) (time.Time, error) {
-	var ts time.Time
-	t.mu.Lock()
-	t.state = txClosed // No futher operations after commit.
-	mPb, err := mutationsProto(t.wb)
-	t.mu.Unlock()
-	if err != nil {
-		return ts, err
-	}
-	// In case that sessionHandle was destroyed but transaction body fails to report it.
-	sid, client := t.sh.getID(), t.sh.getClient()
-	if sid == "" || client == nil {
-		return ts, errSessionClosed(t.sh)
-	}
-	err = runRetryable(contextWithOutgoingMetadata(ctx, t.sh.getMetadata()), func(ctx context.Context) error {
-		var trailer metadata.MD
-		res, e := client.Commit(ctx, &sppb.CommitRequest{
-			Session: sid,
-			Transaction: &sppb.CommitRequest_TransactionId{
-				TransactionId: t.tx,
-			},
-			Mutations: mPb,
-		}, grpc.Trailer(&trailer))
-		if e != nil {
-			return toSpannerErrorWithMetadata(e, trailer)
-		}
-		if tstamp := res.GetCommitTimestamp(); tstamp != nil {
-			ts = time.Unix(tstamp.Seconds, int64(tstamp.Nanos))
-		}
-		return nil
-	})
-	if shouldDropSession(err) {
-		t.sh.destroy()
-	}
-	return ts, err
-}
-
-// rollback is called when a commit is aborted or the transaction body runs into error.
-func (t *ReadWriteTransaction) rollback(ctx context.Context) {
-	t.mu.Lock()
-	// Forbid further operations on rollbacked transaction.
-	t.state = txClosed
-	t.mu.Unlock()
-	// In case that sessionHandle was destroyed but transaction body fails to report it.
-	sid, client := t.sh.getID(), t.sh.getClient()
-	if sid == "" || client == nil {
-		return
-	}
-	err := runRetryable(contextWithOutgoingMetadata(ctx, t.sh.getMetadata()), func(ctx context.Context) error {
-		_, e := client.Rollback(ctx, &sppb.RollbackRequest{
-			Session:       sid,
-			TransactionId: t.tx,
-		})
-		return e
-	})
-	if shouldDropSession(err) {
-		t.sh.destroy()
-	}
-	return
-}
-
-// runInTransaction executes f under a read-write transaction context.
-func (t *ReadWriteTransaction) runInTransaction(ctx context.Context, f func(context.Context, *ReadWriteTransaction) error) (time.Time, error) {
-	var (
-		ts  time.Time
-		err error
-	)
-	if err = f(context.WithValue(ctx, transactionInProgressKey{}, 1), t); err == nil {
-		// Try to commit if transaction body returns no error.
-		ts, err = t.commit(ctx)
-	}
-	if err != nil {
-		if isAbortErr(err) {
-			// Retry the transaction using the same session on ABORT error.
-			// Cloud Spanner will create the new transaction with the previous one's wound-wait priority.
-			err = errRetry(err)
-			return ts, err
-		}
-		// Not going to commit, according to API spec, should rollback the transaction.
-		t.rollback(ctx)
-		return ts, err
-	}
-	// err == nil, return commit timestamp.
-	return ts, err
-}
-
-// writeOnlyTransaction provides the most efficient way of doing write-only transactions. It essentially does blind writes to Cloud Spanner.
-type writeOnlyTransaction struct {
-	// sp is the session pool which writeOnlyTransaction uses to get Cloud Spanner sessions for blind writes.
-	sp *sessionPool
-}
-
-// applyAtLeastOnce commits a list of mutations to Cloud Spanner for at least once, unless one of the following happends:
-//     1) Context is timeout.
-//     2) An unretryable error(e.g. database not found) occurs.
-//     3) There is a malformed Mutation object.
-func (t *writeOnlyTransaction) applyAtLeastOnce(ctx context.Context, ms ...*Mutation) (time.Time, error) {
-	var (
-		ts time.Time
-		sh *sessionHandle
-	)
-	mPb, err := mutationsProto(ms)
-	if err != nil {
-		// Malformed mutation found, just return the error.
-		return ts, err
-	}
-	err = runRetryable(ctx, func(ct context.Context) error {
-		var e error
-		var trailers metadata.MD
-		if sh == nil || sh.getID() == "" || sh.getClient() == nil {
-			// No usable session for doing the commit, take one from pool.
-			sh, e = t.sp.take(ctx)
-			if e != nil {
-				// sessionPool.Take already retries for session creations/retrivals.
-				return e
-			}
-		}
-		res, e := sh.getClient().Commit(contextWithOutgoingMetadata(ctx, sh.getMetadata()), &sppb.CommitRequest{
-			Session: sh.getID(),
-			Transaction: &sppb.CommitRequest_SingleUseTransaction{
-				SingleUseTransaction: &sppb.TransactionOptions{
-					Mode: &sppb.TransactionOptions_ReadWrite_{
-						ReadWrite: &sppb.TransactionOptions_ReadWrite{},
-					},
-				},
-			},
-			Mutations: mPb,
-		}, grpc.Trailer(&trailers))
-		if e != nil {
-			if isAbortErr(e) {
-				// Mask ABORT error as retryable, because aborted transactions are allowed to be retried.
-				return errRetry(toSpannerErrorWithMetadata(e, trailers))
-			}
-			if shouldDropSession(e) {
-				// Discard the bad session.
-				sh.destroy()
-			}
-			return e
-		}
-		if tstamp := res.GetCommitTimestamp(); tstamp != nil {
-			ts = time.Unix(tstamp.Seconds, int64(tstamp.Nanos))
-		}
-		return nil
-	})
-	if sh != nil {
-		sh.recycle()
-	}
-	return ts, err
-}
-
-// isAbortedErr returns true if the error indicates that an gRPC call is aborted on the server side.
-func isAbortErr(err error) bool {
-	if err == nil {
-		return false
-	}
-	if ErrCode(err) == codes.Aborted {
-		return true
-	}
-	return false
-}
diff --git a/vendor/cloud.google.com/go/spanner/value.go b/vendor/cloud.google.com/go/spanner/value.go
deleted file mode 100644
index c09713264..000000000
--- a/vendor/cloud.google.com/go/spanner/value.go
+++ /dev/null
@@ -1,1244 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"encoding/base64"
-	"fmt"
-	"math"
-	"reflect"
-	"strconv"
-	"strings"
-	"time"
-
-	"cloud.google.com/go/civil"
-	"cloud.google.com/go/internal/fields"
-	proto "github.com/golang/protobuf/proto"
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-	"google.golang.org/grpc/codes"
-)
-
-// NullInt64 represents a Cloud Spanner INT64 that may be NULL.
-type NullInt64 struct {
-	Int64 int64
-	Valid bool // Valid is true if Int64 is not NULL.
-}
-
-// String implements Stringer.String for NullInt64
-func (n NullInt64) String() string {
-	if !n.Valid {
-		return fmt.Sprintf("%v", "<null>")
-	}
-	return fmt.Sprintf("%v", n.Int64)
-}
-
-// NullString represents a Cloud Spanner STRING that may be NULL.
-type NullString struct {
-	StringVal string
-	Valid     bool // Valid is true if StringVal is not NULL.
-}
-
-// String implements Stringer.String for NullString
-func (n NullString) String() string {
-	if !n.Valid {
-		return fmt.Sprintf("%v", "<null>")
-	}
-	return fmt.Sprintf("%q", n.StringVal)
-}
-
-// NullFloat64 represents a Cloud Spanner FLOAT64 that may be NULL.
-type NullFloat64 struct {
-	Float64 float64
-	Valid   bool // Valid is true if Float64 is not NULL.
-}
-
-// String implements Stringer.String for NullFloat64
-func (n NullFloat64) String() string {
-	if !n.Valid {
-		return fmt.Sprintf("%v", "<null>")
-	}
-	return fmt.Sprintf("%v", n.Float64)
-}
-
-// NullBool represents a Cloud Spanner BOOL that may be NULL.
-type NullBool struct {
-	Bool  bool
-	Valid bool // Valid is true if Bool is not NULL.
-}
-
-// String implements Stringer.String for NullBool
-func (n NullBool) String() string {
-	if !n.Valid {
-		return fmt.Sprintf("%v", "<null>")
-	}
-	return fmt.Sprintf("%v", n.Bool)
-}
-
-// NullTime represents a Cloud Spanner TIMESTAMP that may be null.
-type NullTime struct {
-	Time  time.Time
-	Valid bool // Valid is true if Time is not NULL.
-}
-
-// String implements Stringer.String for NullTime
-func (n NullTime) String() string {
-	if !n.Valid {
-		return fmt.Sprintf("%s", "<null>")
-	}
-	return fmt.Sprintf("%q", n.Time.Format(time.RFC3339Nano))
-}
-
-// NullDate represents a Cloud Spanner DATE that may be null.
-type NullDate struct {
-	Date  civil.Date
-	Valid bool // Valid is true if Date is not NULL.
-}
-
-// String implements Stringer.String for NullDate
-func (n NullDate) String() string {
-	if !n.Valid {
-		return fmt.Sprintf("%s", "<null>")
-	}
-	return fmt.Sprintf("%q", n.Date)
-}
-
-// NullRow represents a Cloud Spanner STRUCT that may be NULL.
-// See also the document for Row.
-// Note that NullRow is not a valid Cloud Spanner column Type.
-type NullRow struct {
-	Row   Row
-	Valid bool // Valid is true if Row is not NULL.
-}
-
-// GenericColumnValue represents the generic encoded value and type of the
-// column.  See google.spanner.v1.ResultSet proto for details.  This can be
-// useful for proxying query results when the result types are not known in
-// advance.
-type GenericColumnValue struct {
-	Type  *sppb.Type
-	Value *proto3.Value
-}
-
-// Decode decodes a GenericColumnValue. The ptr argument should be a pointer
-// to a Go value that can accept v.
-func (v GenericColumnValue) Decode(ptr interface{}) error {
-	return decodeValue(v.Value, v.Type, ptr)
-}
-
-// NewGenericColumnValue creates a GenericColumnValue from Go value that is
-// valid for Cloud Spanner.
-func newGenericColumnValue(v interface{}) (*GenericColumnValue, error) {
-	value, typ, err := encodeValue(v)
-	if err != nil {
-		return nil, err
-	}
-	return &GenericColumnValue{Value: value, Type: typ}, nil
-}
-
-// errTypeMismatch returns error for destination not having a compatible type
-// with source Cloud Spanner type.
-func errTypeMismatch(srcType sppb.TypeCode, isArray bool, dst interface{}) error {
-	usage := srcType.String()
-	if isArray {
-		usage = fmt.Sprintf("%v[%v]", sppb.TypeCode_ARRAY, srcType)
-	}
-	return spannerErrorf(codes.InvalidArgument, "type %T cannot be used for decoding %v", dst, usage)
-}
-
-// errNilSpannerType returns error for nil Cloud Spanner type in decoding.
-func errNilSpannerType() error {
-	return spannerErrorf(codes.FailedPrecondition, "unexpected nil Cloud Spanner data type in decoding")
-}
-
-// errNilSrc returns error for decoding from nil proto value.
-func errNilSrc() error {
-	return spannerErrorf(codes.FailedPrecondition, "unexpected nil Cloud Spanner value in decoding")
-}
-
-// errNilDst returns error for decoding into nil interface{}.
-func errNilDst(dst interface{}) error {
-	return spannerErrorf(codes.InvalidArgument, "cannot decode into nil type %T", dst)
-}
-
-// errNilArrElemType returns error for input Cloud Spanner data type being a array but without a
-// non-nil array element type.
-func errNilArrElemType(t *sppb.Type) error {
-	return spannerErrorf(codes.FailedPrecondition, "array type %v is with nil array element type", t)
-}
-
-// errDstNotForNull returns error for decoding a SQL NULL value into a destination which doesn't
-// support NULL values.
-func errDstNotForNull(dst interface{}) error {
-	return spannerErrorf(codes.InvalidArgument, "destination %T cannot support NULL SQL values", dst)
-}
-
-// errBadEncoding returns error for decoding wrongly encoded types.
-func errBadEncoding(v *proto3.Value, err error) error {
-	return spannerErrorf(codes.FailedPrecondition, "%v wasn't correctly encoded: <%v>", v, err)
-}
-
-func parseNullTime(v *proto3.Value, p *NullTime, code sppb.TypeCode, isNull bool) error {
-	if p == nil {
-		return errNilDst(p)
-	}
-	if code != sppb.TypeCode_TIMESTAMP {
-		return errTypeMismatch(code, false, p)
-	}
-	if isNull {
-		*p = NullTime{}
-		return nil
-	}
-	x, err := getStringValue(v)
-	if err != nil {
-		return err
-	}
-	y, err := time.Parse(time.RFC3339Nano, x)
-	if err != nil {
-		return errBadEncoding(v, err)
-	}
-	p.Valid = true
-	p.Time = y
-	return nil
-}
-
-// decodeValue decodes a protobuf Value into a pointer to a Go value, as
-// specified by sppb.Type.
-func decodeValue(v *proto3.Value, t *sppb.Type, ptr interface{}) error {
-	if v == nil {
-		return errNilSrc()
-	}
-	if t == nil {
-		return errNilSpannerType()
-	}
-	code := t.Code
-	acode := sppb.TypeCode_TYPE_CODE_UNSPECIFIED
-	if code == sppb.TypeCode_ARRAY {
-		if t.ArrayElementType == nil {
-			return errNilArrElemType(t)
-		}
-		acode = t.ArrayElementType.Code
-	}
-	typeErr := errTypeMismatch(code, false, ptr)
-	if code == sppb.TypeCode_ARRAY {
-		typeErr = errTypeMismatch(acode, true, ptr)
-	}
-	nullErr := errDstNotForNull(ptr)
-	_, isNull := v.Kind.(*proto3.Value_NullValue)
-
-	// Do the decoding based on the type of ptr.
-	switch p := ptr.(type) {
-	case nil:
-		return errNilDst(nil)
-	case *string:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if code != sppb.TypeCode_STRING {
-			return typeErr
-		}
-		if isNull {
-			return nullErr
-		}
-		x, err := getStringValue(v)
-		if err != nil {
-			return err
-		}
-		*p = x
-	case *NullString:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if code != sppb.TypeCode_STRING {
-			return typeErr
-		}
-		if isNull {
-			*p = NullString{}
-			break
-		}
-		x, err := getStringValue(v)
-		if err != nil {
-			return err
-		}
-		p.Valid = true
-		p.StringVal = x
-	case *[]NullString:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if acode != sppb.TypeCode_STRING {
-			return typeErr
-		}
-		if isNull {
-			*p = nil
-			break
-		}
-		x, err := getListValue(v)
-		if err != nil {
-			return err
-		}
-		y, err := decodeStringArray(x)
-		if err != nil {
-			return err
-		}
-		*p = y
-	case *[]byte:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if code != sppb.TypeCode_BYTES {
-			return typeErr
-		}
-		if isNull {
-			*p = nil
-			break
-		}
-		x, err := getStringValue(v)
-		if err != nil {
-			return err
-		}
-		y, err := base64.StdEncoding.DecodeString(x)
-		if err != nil {
-			return errBadEncoding(v, err)
-		}
-		*p = y
-	case *[][]byte:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if acode != sppb.TypeCode_BYTES {
-			return typeErr
-		}
-		if isNull {
-			*p = nil
-			break
-		}
-		x, err := getListValue(v)
-		if err != nil {
-			return err
-		}
-		y, err := decodeByteArray(x)
-		if err != nil {
-			return err
-		}
-		*p = y
-	case *int64:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if code != sppb.TypeCode_INT64 {
-			return typeErr
-		}
-		if isNull {
-			return nullErr
-		}
-		x, err := getStringValue(v)
-		if err != nil {
-			return err
-		}
-		y, err := strconv.ParseInt(x, 10, 64)
-		if err != nil {
-			return errBadEncoding(v, err)
-		}
-		*p = y
-	case *NullInt64:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if code != sppb.TypeCode_INT64 {
-			return typeErr
-		}
-		if isNull {
-			*p = NullInt64{}
-			break
-		}
-		x, err := getStringValue(v)
-		if err != nil {
-			return err
-		}
-		y, err := strconv.ParseInt(x, 10, 64)
-		if err != nil {
-			return errBadEncoding(v, err)
-		}
-		p.Valid = true
-		p.Int64 = y
-	case *[]NullInt64:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if acode != sppb.TypeCode_INT64 {
-			return typeErr
-		}
-		if isNull {
-			*p = nil
-			break
-		}
-		x, err := getListValue(v)
-		if err != nil {
-			return err
-		}
-		y, err := decodeIntArray(x)
-		if err != nil {
-			return err
-		}
-		*p = y
-	case *bool:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if code != sppb.TypeCode_BOOL {
-			return typeErr
-		}
-		if isNull {
-			return nullErr
-		}
-		x, err := getBoolValue(v)
-		if err != nil {
-			return err
-		}
-		*p = x
-	case *NullBool:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if code != sppb.TypeCode_BOOL {
-			return typeErr
-		}
-		if isNull {
-			*p = NullBool{}
-			break
-		}
-		x, err := getBoolValue(v)
-		if err != nil {
-			return err
-		}
-		p.Valid = true
-		p.Bool = x
-	case *[]NullBool:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if acode != sppb.TypeCode_BOOL {
-			return typeErr
-		}
-		if isNull {
-			*p = nil
-			break
-		}
-		x, err := getListValue(v)
-		if err != nil {
-			return err
-		}
-		y, err := decodeBoolArray(x)
-		if err != nil {
-			return err
-		}
-		*p = y
-	case *float64:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if code != sppb.TypeCode_FLOAT64 {
-			return typeErr
-		}
-		if isNull {
-			return nullErr
-		}
-		x, err := getFloat64Value(v)
-		if err != nil {
-			return err
-		}
-		*p = x
-	case *NullFloat64:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if code != sppb.TypeCode_FLOAT64 {
-			return typeErr
-		}
-		if isNull {
-			*p = NullFloat64{}
-			break
-		}
-		x, err := getFloat64Value(v)
-		if err != nil {
-			return err
-		}
-		p.Valid = true
-		p.Float64 = x
-	case *[]NullFloat64:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if acode != sppb.TypeCode_FLOAT64 {
-			return typeErr
-		}
-		if isNull {
-			*p = nil
-			break
-		}
-		x, err := getListValue(v)
-		if err != nil {
-			return err
-		}
-		y, err := decodeFloat64Array(x)
-		if err != nil {
-			return err
-		}
-		*p = y
-	case *time.Time:
-		var nt NullTime
-		if isNull {
-			return nullErr
-		}
-		err := parseNullTime(v, &nt, code, isNull)
-		if err != nil {
-			return nil
-		}
-		*p = nt.Time
-	case *NullTime:
-		err := parseNullTime(v, p, code, isNull)
-		if err != nil {
-			return err
-		}
-	case *[]NullTime:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if acode != sppb.TypeCode_TIMESTAMP {
-			return typeErr
-		}
-		if isNull {
-			*p = nil
-			break
-		}
-		x, err := getListValue(v)
-		if err != nil {
-			return err
-		}
-		y, err := decodeTimeArray(x)
-		if err != nil {
-			return err
-		}
-		*p = y
-	case *civil.Date:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if code != sppb.TypeCode_DATE {
-			return typeErr
-		}
-		if isNull {
-			return nullErr
-		}
-		x, err := getStringValue(v)
-		if err != nil {
-			return err
-		}
-		y, err := civil.ParseDate(x)
-		if err != nil {
-			return errBadEncoding(v, err)
-		}
-		*p = y
-	case *NullDate:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if code != sppb.TypeCode_DATE {
-			return typeErr
-		}
-		if isNull {
-			*p = NullDate{}
-			break
-		}
-		x, err := getStringValue(v)
-		if err != nil {
-			return err
-		}
-		y, err := civil.ParseDate(x)
-		if err != nil {
-			return errBadEncoding(v, err)
-		}
-		p.Valid = true
-		p.Date = y
-	case *[]NullDate:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if acode != sppb.TypeCode_DATE {
-			return typeErr
-		}
-		if isNull {
-			*p = nil
-			break
-		}
-		x, err := getListValue(v)
-		if err != nil {
-			return err
-		}
-		y, err := decodeDateArray(x)
-		if err != nil {
-			return err
-		}
-		*p = y
-	case *[]NullRow:
-		if p == nil {
-			return errNilDst(p)
-		}
-		if acode != sppb.TypeCode_STRUCT {
-			return typeErr
-		}
-		if isNull {
-			*p = nil
-			break
-		}
-		x, err := getListValue(v)
-		if err != nil {
-			return err
-		}
-		y, err := decodeRowArray(t.ArrayElementType.StructType, x)
-		if err != nil {
-			return err
-		}
-		*p = y
-	case *GenericColumnValue:
-		*p = GenericColumnValue{
-			// Deep clone to ensure subsequent changes to t or v
-			// don't affect our decoded value.
-			Type:  proto.Clone(t).(*sppb.Type),
-			Value: proto.Clone(v).(*proto3.Value),
-		}
-	default:
-		// Check if the proto encoding is for an array of structs.
-		if !(code == sppb.TypeCode_ARRAY && acode == sppb.TypeCode_STRUCT) {
-			return typeErr
-		}
-		vp := reflect.ValueOf(p)
-		if !vp.IsValid() {
-			return errNilDst(p)
-		}
-		if !isPtrStructPtrSlice(vp.Type()) {
-			// The container is not a pointer to a struct pointer slice.
-			return typeErr
-		}
-		// Only use reflection for nil detection on slow path.
-		// Also, IsNil panics on many types, so check it after the type check.
-		if vp.IsNil() {
-			return errNilDst(p)
-		}
-		if isNull {
-			// The proto Value is encoding NULL, set the pointer to struct
-			// slice to nil as well.
-			vp.Elem().Set(reflect.Zero(vp.Elem().Type()))
-			break
-		}
-		x, err := getListValue(v)
-		if err != nil {
-			return err
-		}
-		if err = decodeStructArray(t.ArrayElementType.StructType, x, p); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-// errSrvVal returns an error for getting a wrong source protobuf value in decoding.
-func errSrcVal(v *proto3.Value, want string) error {
-	return spannerErrorf(codes.FailedPrecondition, "cannot use %v(Kind: %T) as %s Value",
-		v, v.GetKind(), want)
-}
-
-// getStringValue returns the string value encoded in proto3.Value v whose
-// kind is proto3.Value_StringValue.
-func getStringValue(v *proto3.Value) (string, error) {
-	if x, ok := v.GetKind().(*proto3.Value_StringValue); ok && x != nil {
-		return x.StringValue, nil
-	}
-	return "", errSrcVal(v, "String")
-}
-
-// getBoolValue returns the bool value encoded in proto3.Value v whose
-// kind is proto3.Value_BoolValue.
-func getBoolValue(v *proto3.Value) (bool, error) {
-	if x, ok := v.GetKind().(*proto3.Value_BoolValue); ok && x != nil {
-		return x.BoolValue, nil
-	}
-	return false, errSrcVal(v, "Bool")
-}
-
-// getListValue returns the proto3.ListValue contained in proto3.Value v whose
-// kind is proto3.Value_ListValue.
-func getListValue(v *proto3.Value) (*proto3.ListValue, error) {
-	if x, ok := v.GetKind().(*proto3.Value_ListValue); ok && x != nil {
-		return x.ListValue, nil
-	}
-	return nil, errSrcVal(v, "List")
-}
-
-// errUnexpectedNumStr returns error for decoder getting a unexpected string for
-// representing special float values.
-func errUnexpectedNumStr(s string) error {
-	return spannerErrorf(codes.FailedPrecondition, "unexpected string value %q for number", s)
-}
-
-// getFloat64Value returns the float64 value encoded in proto3.Value v whose
-// kind is proto3.Value_NumberValue / proto3.Value_StringValue.
-// Cloud Spanner uses string to encode NaN, Infinity and -Infinity.
-func getFloat64Value(v *proto3.Value) (float64, error) {
-	switch x := v.GetKind().(type) {
-	case *proto3.Value_NumberValue:
-		if x == nil {
-			break
-		}
-		return x.NumberValue, nil
-	case *proto3.Value_StringValue:
-		if x == nil {
-			break
-		}
-		switch x.StringValue {
-		case "NaN":
-			return math.NaN(), nil
-		case "Infinity":
-			return math.Inf(1), nil
-		case "-Infinity":
-			return math.Inf(-1), nil
-		default:
-			return 0, errUnexpectedNumStr(x.StringValue)
-		}
-	}
-	return 0, errSrcVal(v, "Number")
-}
-
-// errNilListValue returns error for unexpected nil ListValue in decoding Cloud Spanner ARRAYs.
-func errNilListValue(sqlType string) error {
-	return spannerErrorf(codes.FailedPrecondition, "unexpected nil ListValue in decoding %v array", sqlType)
-}
-
-// errDecodeArrayElement returns error for failure in decoding single array element.
-func errDecodeArrayElement(i int, v proto.Message, sqlType string, err error) error {
-	se, ok := toSpannerError(err).(*Error)
-	if !ok {
-		return spannerErrorf(codes.Unknown,
-			"cannot decode %v(array element %v) as %v, error = <%v>", v, i, sqlType, err)
-	}
-	se.decorate(fmt.Sprintf("cannot decode %v(array element %v) as %v", v, i, sqlType))
-	return se
-}
-
-// decodeStringArray decodes proto3.ListValue pb into a NullString slice.
-func decodeStringArray(pb *proto3.ListValue) ([]NullString, error) {
-	if pb == nil {
-		return nil, errNilListValue("STRING")
-	}
-	a := make([]NullString, len(pb.Values))
-	for i, v := range pb.Values {
-		if err := decodeValue(v, stringType(), &a[i]); err != nil {
-			return nil, errDecodeArrayElement(i, v, "STRING", err)
-		}
-	}
-	return a, nil
-}
-
-// decodeIntArray decodes proto3.ListValue pb into a NullInt64 slice.
-func decodeIntArray(pb *proto3.ListValue) ([]NullInt64, error) {
-	if pb == nil {
-		return nil, errNilListValue("INT64")
-	}
-	a := make([]NullInt64, len(pb.Values))
-	for i, v := range pb.Values {
-		if err := decodeValue(v, intType(), &a[i]); err != nil {
-			return nil, errDecodeArrayElement(i, v, "INT64", err)
-		}
-	}
-	return a, nil
-}
-
-// decodeBoolArray decodes proto3.ListValue pb into a NullBool slice.
-func decodeBoolArray(pb *proto3.ListValue) ([]NullBool, error) {
-	if pb == nil {
-		return nil, errNilListValue("BOOL")
-	}
-	a := make([]NullBool, len(pb.Values))
-	for i, v := range pb.Values {
-		if err := decodeValue(v, boolType(), &a[i]); err != nil {
-			return nil, errDecodeArrayElement(i, v, "BOOL", err)
-		}
-	}
-	return a, nil
-}
-
-// decodeFloat64Array decodes proto3.ListValue pb into a NullFloat64 slice.
-func decodeFloat64Array(pb *proto3.ListValue) ([]NullFloat64, error) {
-	if pb == nil {
-		return nil, errNilListValue("FLOAT64")
-	}
-	a := make([]NullFloat64, len(pb.Values))
-	for i, v := range pb.Values {
-		if err := decodeValue(v, floatType(), &a[i]); err != nil {
-			return nil, errDecodeArrayElement(i, v, "FLOAT64", err)
-		}
-	}
-	return a, nil
-}
-
-// decodeByteArray decodes proto3.ListValue pb into a slice of byte slice.
-func decodeByteArray(pb *proto3.ListValue) ([][]byte, error) {
-	if pb == nil {
-		return nil, errNilListValue("BYTES")
-	}
-	a := make([][]byte, len(pb.Values))
-	for i, v := range pb.Values {
-		if err := decodeValue(v, bytesType(), &a[i]); err != nil {
-			return nil, errDecodeArrayElement(i, v, "BYTES", err)
-		}
-	}
-	return a, nil
-}
-
-// decodeTimeArray decodes proto3.ListValue pb into a NullTime slice.
-func decodeTimeArray(pb *proto3.ListValue) ([]NullTime, error) {
-	if pb == nil {
-		return nil, errNilListValue("TIMESTAMP")
-	}
-	a := make([]NullTime, len(pb.Values))
-	for i, v := range pb.Values {
-		if err := decodeValue(v, timeType(), &a[i]); err != nil {
-			return nil, errDecodeArrayElement(i, v, "TIMESTAMP", err)
-		}
-	}
-	return a, nil
-}
-
-// decodeDateArray decodes proto3.ListValue pb into a NullDate slice.
-func decodeDateArray(pb *proto3.ListValue) ([]NullDate, error) {
-	if pb == nil {
-		return nil, errNilListValue("DATE")
-	}
-	a := make([]NullDate, len(pb.Values))
-	for i, v := range pb.Values {
-		if err := decodeValue(v, dateType(), &a[i]); err != nil {
-			return nil, errDecodeArrayElement(i, v, "DATE", err)
-		}
-	}
-	return a, nil
-}
-
-func errNotStructElement(i int, v *proto3.Value) error {
-	return errDecodeArrayElement(i, v, "STRUCT",
-		spannerErrorf(codes.FailedPrecondition, "%v(type: %T) doesn't encode Cloud Spanner STRUCT", v, v))
-}
-
-// decodeRowArray decodes proto3.ListValue pb into a NullRow slice according to
-// the structual information given in sppb.StructType ty.
-func decodeRowArray(ty *sppb.StructType, pb *proto3.ListValue) ([]NullRow, error) {
-	if pb == nil {
-		return nil, errNilListValue("STRUCT")
-	}
-	a := make([]NullRow, len(pb.Values))
-	for i := range pb.Values {
-		switch v := pb.Values[i].GetKind().(type) {
-		case *proto3.Value_ListValue:
-			a[i] = NullRow{
-				Row: Row{
-					fields: ty.Fields,
-					vals:   v.ListValue.Values,
-				},
-				Valid: true,
-			}
-		// Null elements not currently supported by the server, see
-		// https://cloud.google.com/spanner/docs/query-syntax#using-structs-with-select
-		case *proto3.Value_NullValue:
-			// no-op, a[i] is NullRow{} already
-		default:
-			return nil, errNotStructElement(i, pb.Values[i])
-		}
-	}
-	return a, nil
-}
-
-// structFieldColumn returns the name of i-th field of struct type typ if the field
-// is untagged; otherwise, it returns the tagged name of the field.
-func structFieldColumn(typ reflect.Type, i int) (col string, ok bool) {
-	desc := typ.Field(i)
-	if desc.PkgPath != "" || desc.Anonymous {
-		// Skip unexported or anonymous fields.
-		return "", false
-	}
-	col = desc.Name
-	if tag := desc.Tag.Get("spanner"); tag != "" {
-		if tag == "-" {
-			// Skip fields tagged "-" to match encoding/json and others.
-			return "", false
-		}
-		col = tag
-		if idx := strings.Index(tag, ","); idx != -1 {
-			col = tag[:idx]
-		}
-	}
-	return col, true
-}
-
-// errNilSpannerStructType returns error for unexpected nil Cloud Spanner STRUCT schema type in decoding.
-func errNilSpannerStructType() error {
-	return spannerErrorf(codes.FailedPrecondition, "unexpected nil StructType in decoding Cloud Spanner STRUCT")
-}
-
-// errUnnamedField returns error for decoding a Cloud Spanner STRUCT with unnamed field into a Go struct.
-func errUnnamedField(ty *sppb.StructType, i int) error {
-	return spannerErrorf(codes.InvalidArgument, "unnamed field %v in Cloud Spanner STRUCT %+v", i, ty)
-}
-
-// errNoOrDupGoField returns error for decoding a Cloud Spanner
-// STRUCT into a Go struct which is either missing a field, or has duplicate fields.
-func errNoOrDupGoField(s interface{}, f string) error {
-	return spannerErrorf(codes.InvalidArgument, "Go struct %+v(type %T) has no or duplicate fields for Cloud Spanner STRUCT field %v", s, s, f)
-}
-
-// errDupColNames returns error for duplicated Cloud Spanner STRUCT field names found in decoding a Cloud Spanner STRUCT into a Go struct.
-func errDupSpannerField(f string, ty *sppb.StructType) error {
-	return spannerErrorf(codes.InvalidArgument, "duplicated field name %q in Cloud Spanner STRUCT %+v", f, ty)
-}
-
-// errDecodeStructField returns error for failure in decoding a single field of a Cloud Spanner STRUCT.
-func errDecodeStructField(ty *sppb.StructType, f string, err error) error {
-	se, ok := toSpannerError(err).(*Error)
-	if !ok {
-		return spannerErrorf(codes.Unknown,
-			"cannot decode field %v of Cloud Spanner STRUCT %+v, error = <%v>", f, ty, err)
-	}
-	se.decorate(fmt.Sprintf("cannot decode field %v of Cloud Spanner STRUCT %+v", f, ty))
-	return se
-}
-
-// decodeStruct decodes proto3.ListValue pb into struct referenced by pointer ptr, according to
-// the structual information given in sppb.StructType ty.
-func decodeStruct(ty *sppb.StructType, pb *proto3.ListValue, ptr interface{}) error {
-	if reflect.ValueOf(ptr).IsNil() {
-		return errNilDst(ptr)
-	}
-	if ty == nil {
-		return errNilSpannerStructType()
-	}
-	// t holds the structual information of ptr.
-	t := reflect.TypeOf(ptr).Elem()
-	// v is the actual value that ptr points to.
-	v := reflect.ValueOf(ptr).Elem()
-
-	fields, err := fieldCache.Fields(t)
-	if err != nil {
-		return toSpannerError(err)
-	}
-	seen := map[string]bool{}
-	for i, f := range ty.Fields {
-		if f.Name == "" {
-			return errUnnamedField(ty, i)
-		}
-		sf := fields.Match(f.Name)
-		if sf == nil {
-			return errNoOrDupGoField(ptr, f.Name)
-		}
-		if seen[f.Name] {
-			// We don't allow duplicated field name.
-			return errDupSpannerField(f.Name, ty)
-		}
-		// Try to decode a single field.
-		if err := decodeValue(pb.Values[i], f.Type, v.FieldByIndex(sf.Index).Addr().Interface()); err != nil {
-			return errDecodeStructField(ty, f.Name, err)
-		}
-		// Mark field f.Name as processed.
-		seen[f.Name] = true
-	}
-	return nil
-}
-
-// isPtrStructPtrSlice returns true if ptr is a pointer to a slice of struct pointers.
-func isPtrStructPtrSlice(t reflect.Type) bool {
-	if t.Kind() != reflect.Ptr || t.Elem().Kind() != reflect.Slice {
-		// t is not a pointer to a slice.
-		return false
-	}
-	if t = t.Elem(); t.Elem().Kind() != reflect.Ptr || t.Elem().Elem().Kind() != reflect.Struct {
-		// the slice that t points to is not a slice of struct pointers.
-		return false
-	}
-	return true
-}
-
-// decodeStructArray decodes proto3.ListValue pb into struct slice referenced by pointer ptr, according to the
-// structual information given in a sppb.StructType.
-func decodeStructArray(ty *sppb.StructType, pb *proto3.ListValue, ptr interface{}) error {
-	if pb == nil {
-		return errNilListValue("STRUCT")
-	}
-	// Type of the struct pointers stored in the slice that ptr points to.
-	ts := reflect.TypeOf(ptr).Elem().Elem()
-	// The slice that ptr points to, might be nil at this point.
-	v := reflect.ValueOf(ptr).Elem()
-	// Allocate empty slice.
-	v.Set(reflect.MakeSlice(v.Type(), 0, len(pb.Values)))
-	// Decode every struct in pb.Values.
-	for i, pv := range pb.Values {
-		// Check if pv is a NULL value.
-		if _, isNull := pv.Kind.(*proto3.Value_NullValue); isNull {
-			// Append a nil pointer to the slice.
-			v.Set(reflect.Append(v, reflect.New(ts).Elem()))
-			continue
-		}
-		// Allocate empty struct.
-		s := reflect.New(ts.Elem())
-		// Get proto3.ListValue l from proto3.Value pv.
-		l, err := getListValue(pv)
-		if err != nil {
-			return errDecodeArrayElement(i, pv, "STRUCT", err)
-		}
-		// Decode proto3.ListValue l into struct referenced by s.Interface().
-		if err = decodeStruct(ty, l, s.Interface()); err != nil {
-			return errDecodeArrayElement(i, pv, "STRUCT", err)
-		}
-		// Append the decoded struct back into the slice.
-		v.Set(reflect.Append(v, s))
-	}
-	return nil
-}
-
-// errEncoderUnsupportedType returns error for not being able to encode a value of
-// certain type.
-func errEncoderUnsupportedType(v interface{}) error {
-	return spannerErrorf(codes.InvalidArgument, "client doesn't support type %T", v)
-}
-
-// encodeValue encodes a Go native type into a proto3.Value.
-func encodeValue(v interface{}) (*proto3.Value, *sppb.Type, error) {
-	pb := &proto3.Value{
-		Kind: &proto3.Value_NullValue{NullValue: proto3.NullValue_NULL_VALUE},
-	}
-	var pt *sppb.Type
-	var err error
-	switch v := v.(type) {
-	case nil:
-	case string:
-		pb.Kind = stringKind(v)
-		pt = stringType()
-	case NullString:
-		if v.Valid {
-			return encodeValue(v.StringVal)
-		}
-	case []string:
-		if v != nil {
-			pb, err = encodeArray(len(v), func(i int) interface{} { return v[i] })
-			if err != nil {
-				return nil, nil, err
-			}
-			pt = listType(stringType())
-		}
-	case []NullString:
-		if v != nil {
-			pb, err = encodeArray(len(v), func(i int) interface{} { return v[i] })
-			if err != nil {
-				return nil, nil, err
-			}
-			pt = listType(stringType())
-		}
-	case []byte:
-		if v != nil {
-			pb.Kind = stringKind(base64.StdEncoding.EncodeToString(v))
-			pt = bytesType()
-		}
-	case [][]byte:
-		if v != nil {
-			pb, err = encodeArray(len(v), func(i int) interface{} { return v[i] })
-			if err != nil {
-				return nil, nil, err
-			}
-			pt = listType(bytesType())
-		}
-	case int:
-		pb.Kind = stringKind(strconv.FormatInt(int64(v), 10))
-		pt = intType()
-	case []int:
-		if v != nil {
-			pb, err = encodeArray(len(v), func(i int) interface{} { return v[i] })
-			if err != nil {
-				return nil, nil, err
-			}
-			pt = listType(intType())
-		}
-	case int64:
-		pb.Kind = stringKind(strconv.FormatInt(v, 10))
-		pt = intType()
-	case []int64:
-		if v != nil {
-			pb, err = encodeArray(len(v), func(i int) interface{} { return v[i] })
-			if err != nil {
-				return nil, nil, err
-			}
-			pt = listType(intType())
-		}
-	case NullInt64:
-		if v.Valid {
-			return encodeValue(v.Int64)
-		}
-	case []NullInt64:
-		if v != nil {
-			pb, err = encodeArray(len(v), func(i int) interface{} { return v[i] })
-			if err != nil {
-				return nil, nil, err
-			}
-			pt = listType(intType())
-		}
-	case bool:
-		pb.Kind = &proto3.Value_BoolValue{BoolValue: v}
-		pt = boolType()
-	case []bool:
-		if v != nil {
-			pb, err = encodeArray(len(v), func(i int) interface{} { return v[i] })
-			if err != nil {
-				return nil, nil, err
-			}
-			pt = listType(boolType())
-		}
-	case NullBool:
-		if v.Valid {
-			return encodeValue(v.Bool)
-		}
-	case []NullBool:
-		if v != nil {
-			pb, err = encodeArray(len(v), func(i int) interface{} { return v[i] })
-			if err != nil {
-				return nil, nil, err
-			}
-			pt = listType(boolType())
-		}
-	case float64:
-		pb.Kind = &proto3.Value_NumberValue{NumberValue: v}
-		pt = floatType()
-	case []float64:
-		if v != nil {
-			pb, err = encodeArray(len(v), func(i int) interface{} { return v[i] })
-			if err != nil {
-				return nil, nil, err
-			}
-			pt = listType(floatType())
-		}
-	case NullFloat64:
-		if v.Valid {
-			return encodeValue(v.Float64)
-		}
-	case []NullFloat64:
-		if v != nil {
-			pb, err = encodeArray(len(v), func(i int) interface{} { return v[i] })
-			if err != nil {
-				return nil, nil, err
-			}
-			pt = listType(floatType())
-		}
-	case time.Time:
-		pb.Kind = stringKind(v.UTC().Format(time.RFC3339Nano))
-		pt = timeType()
-	case []time.Time:
-		if v != nil {
-			pb, err = encodeArray(len(v), func(i int) interface{} { return v[i] })
-			if err != nil {
-				return nil, nil, err
-			}
-			pt = listType(timeType())
-		}
-	case NullTime:
-		if v.Valid {
-			return encodeValue(v.Time)
-		}
-	case []NullTime:
-		if v != nil {
-			pb, err = encodeArray(len(v), func(i int) interface{} { return v[i] })
-			if err != nil {
-				return nil, nil, err
-			}
-			pt = listType(timeType())
-		}
-	case civil.Date:
-		pb.Kind = stringKind(v.String())
-		pt = dateType()
-	case []civil.Date:
-		if v != nil {
-			pb, err = encodeArray(len(v), func(i int) interface{} { return v[i] })
-			if err != nil {
-				return nil, nil, err
-			}
-			pt = listType(dateType())
-		}
-	case NullDate:
-		if v.Valid {
-			return encodeValue(v.Date)
-		}
-	case []NullDate:
-		if v != nil {
-			pb, err = encodeArray(len(v), func(i int) interface{} { return v[i] })
-			if err != nil {
-				return nil, nil, err
-			}
-			pt = listType(dateType())
-		}
-	case GenericColumnValue:
-		// Deep clone to ensure subsequent changes to v before
-		// transmission don't affect our encoded value.
-		pb = proto.Clone(v.Value).(*proto3.Value)
-		pt = proto.Clone(v.Type).(*sppb.Type)
-	default:
-		return nil, nil, errEncoderUnsupportedType(v)
-	}
-	return pb, pt, nil
-}
-
-// encodeValueArray encodes a Value array into a proto3.ListValue.
-func encodeValueArray(vs []interface{}) (*proto3.ListValue, error) {
-	lv := &proto3.ListValue{}
-	lv.Values = make([]*proto3.Value, 0, len(vs))
-	for _, v := range vs {
-		pb, _, err := encodeValue(v)
-		if err != nil {
-			return nil, err
-		}
-		lv.Values = append(lv.Values, pb)
-	}
-	return lv, nil
-}
-
-// encodeArray assumes that all values of the array element type encode without error.
-func encodeArray(len int, at func(int) interface{}) (*proto3.Value, error) {
-	vs := make([]*proto3.Value, len)
-	var err error
-	for i := 0; i < len; i++ {
-		vs[i], _, err = encodeValue(at(i))
-		if err != nil {
-			return nil, err
-		}
-	}
-	return listProto(vs...), nil
-}
-
-func spannerTagParser(t reflect.StructTag) (name string, keep bool, other interface{}, err error) {
-	if s := t.Get("spanner"); s != "" {
-		if s == "-" {
-			return "", false, nil, nil
-		}
-		return s, true, nil, nil
-	}
-	return "", true, nil, nil
-}
-
-var fieldCache = fields.NewCache(spannerTagParser, nil, nil)
diff --git a/vendor/cloud.google.com/go/spanner/value_test.go b/vendor/cloud.google.com/go/spanner/value_test.go
deleted file mode 100644
index 00748b0a1..000000000
--- a/vendor/cloud.google.com/go/spanner/value_test.go
+++ /dev/null
@@ -1,611 +0,0 @@
-/*
-Copyright 2017 Google Inc. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package spanner
-
-import (
-	"math"
-	"reflect"
-	"testing"
-	"time"
-
-	"cloud.google.com/go/civil"
-	"github.com/golang/protobuf/proto"
-	proto3 "github.com/golang/protobuf/ptypes/struct"
-	sppb "google.golang.org/genproto/googleapis/spanner/v1"
-)
-
-var (
-	t1 = mustParseTime("2016-11-15T15:04:05.999999999Z")
-	// Boundaries
-	t2 = mustParseTime("0000-01-01T00:00:00.000000000Z")
-	t3 = mustParseTime("9999-12-31T23:59:59.999999999Z")
-	// Local timezone
-	t4 = time.Now()
-	d1 = mustParseDate("2016-11-15")
-	d2 = mustParseDate("1678-01-01")
-)
-
-func mustParseTime(s string) time.Time {
-	t, err := time.Parse(time.RFC3339Nano, s)
-	if err != nil {
-		panic(err)
-	}
-	return t
-}
-
-func mustParseDate(s string) civil.Date {
-	d, err := civil.ParseDate(s)
-	if err != nil {
-		panic(err)
-	}
-	return d
-}
-
-// Test encoding Values.
-func TestEncodeValue(t *testing.T) {
-	var (
-		tString = stringType()
-		tInt    = intType()
-		tBool   = boolType()
-		tFloat  = floatType()
-		tBytes  = bytesType()
-		tTime   = timeType()
-		tDate   = dateType()
-	)
-	for i, test := range []struct {
-		in       interface{}
-		want     *proto3.Value
-		wantType *sppb.Type
-	}{
-		// STRING / STRING ARRAY
-		{"abc", stringProto("abc"), tString},
-		{NullString{"abc", true}, stringProto("abc"), tString},
-		{NullString{"abc", false}, nullProto(), nil},
-		{[]string{"abc", "bcd"}, listProto(stringProto("abc"), stringProto("bcd")), listType(tString)},
-		{[]NullString{{"abcd", true}, {"xyz", false}}, listProto(stringProto("abcd"), nullProto()), listType(tString)},
-		// BYTES / BYTES ARRAY
-		{[]byte("foo"), bytesProto([]byte("foo")), tBytes},
-		{[]byte(nil), nullProto(), nil},
-		{[][]byte{nil, []byte("ab")}, listProto(nullProto(), bytesProto([]byte("ab"))), listType(tBytes)},
-		{[][]byte(nil), nullProto(), nil},
-		// INT64 / INT64 ARRAY
-		{7, intProto(7), tInt},
-		{[]int{31, 127}, listProto(intProto(31), intProto(127)), listType(tInt)},
-		{int64(81), intProto(81), tInt},
-		{[]int64{33, 129}, listProto(intProto(33), intProto(129)), listType(tInt)},
-		{NullInt64{11, true}, intProto(11), tInt},
-		{NullInt64{11, false}, nullProto(), nil},
-		{[]NullInt64{{35, true}, {131, false}}, listProto(intProto(35), nullProto()), listType(tInt)},
-		// BOOL / BOOL ARRAY
-		{true, boolProto(true), tBool},
-		{NullBool{true, true}, boolProto(true), tBool},
-		{NullBool{true, false}, nullProto(), nil},
-		{[]bool{true, false}, listProto(boolProto(true), boolProto(false)), listType(tBool)},
-		{[]NullBool{{true, true}, {true, false}}, listProto(boolProto(true), nullProto()), listType(tBool)},
-		// FLOAT64 / FLOAT64 ARRAY
-		{3.14, floatProto(3.14), tFloat},
-		{NullFloat64{3.1415, true}, floatProto(3.1415), tFloat},
-		{NullFloat64{math.Inf(1), true}, floatProto(math.Inf(1)), tFloat},
-		{NullFloat64{3.14159, false}, nullProto(), nil},
-		{[]float64{3.141, 0.618, math.Inf(-1)}, listProto(floatProto(3.141), floatProto(0.618), floatProto(math.Inf(-1))), listType(tFloat)},
-		{[]NullFloat64{{3.141, true}, {0.618, false}}, listProto(floatProto(3.141), nullProto()), listType(tFloat)},
-		// TIMESTAMP / TIMESTAMP ARRAY
-		{t1, timeProto(t1), tTime},
-		{NullTime{t1, true}, timeProto(t1), tTime},
-		{NullTime{t1, false}, nullProto(), nil},
-		{[]time.Time{t1, t2, t3, t4}, listProto(timeProto(t1), timeProto(t2), timeProto(t3), timeProto(t4)), listType(tTime)},
-		{[]NullTime{{t1, true}, {t1, false}}, listProto(timeProto(t1), nullProto()), listType(tTime)},
-		// DATE / DATE ARRAY
-		{d1, dateProto(d1), tDate},
-		{NullDate{d1, true}, dateProto(d1), tDate},
-		{NullDate{civil.Date{}, false}, nullProto(), nil},
-		{[]civil.Date{d1, d2}, listProto(dateProto(d1), dateProto(d2)), listType(tDate)},
-		{[]NullDate{{d1, true}, {civil.Date{}, false}}, listProto(dateProto(d1), nullProto()), listType(tDate)},
-		// GenericColumnValue
-		{GenericColumnValue{tString, stringProto("abc")}, stringProto("abc"), tString},
-		{GenericColumnValue{tString, nullProto()}, nullProto(), tString},
-		// not actually valid (stringProto inside int list), but demonstrates pass-through.
-		{
-			GenericColumnValue{
-				Type:  listType(tInt),
-				Value: listProto(intProto(5), nullProto(), stringProto("bcd")),
-			},
-			listProto(intProto(5), nullProto(), stringProto("bcd")),
-			listType(tInt),
-		},
-	} {
-		got, gotType, err := encodeValue(test.in)
-		if err != nil {
-			t.Fatalf("#%d: got error during encoding: %v, want nil", i, err)
-		}
-		if !reflect.DeepEqual(got, test.want) {
-			t.Errorf("#%d: got encode result: %v, want %v", i, got, test.want)
-		}
-		if !reflect.DeepEqual(gotType, test.wantType) {
-			t.Errorf("#%d: got encode type: %v, want %v", i, gotType, test.wantType)
-		}
-	}
-}
-
-// Test decoding Values.
-func TestDecodeValue(t *testing.T) {
-	for i, test := range []struct {
-		in   *proto3.Value
-		t    *sppb.Type
-		want interface{}
-		fail bool
-	}{
-		// STRING
-		{stringProto("abc"), stringType(), "abc", false},
-		{nullProto(), stringType(), "abc", true},
-		{stringProto("abc"), stringType(), NullString{"abc", true}, false},
-		{nullProto(), stringType(), NullString{}, false},
-		// STRING ARRAY
-		{
-			listProto(stringProto("abc"), nullProto(), stringProto("bcd")),
-			listType(stringType()),
-			[]NullString{{"abc", true}, {}, {"bcd", true}},
-			false,
-		},
-		{nullProto(), listType(stringType()), []NullString(nil), false},
-		// BYTES
-		{bytesProto([]byte("ab")), bytesType(), []byte("ab"), false},
-		{nullProto(), bytesType(), []byte(nil), false},
-		// BYTES ARRAY
-		{listProto(bytesProto([]byte("ab")), nullProto()), listType(bytesType()), [][]byte{[]byte("ab"), nil}, false},
-		{nullProto(), listType(bytesType()), [][]byte(nil), false},
-		//INT64
-		{intProto(15), intType(), int64(15), false},
-		{nullProto(), intType(), int64(0), true},
-		{intProto(15), intType(), NullInt64{15, true}, false},
-		{nullProto(), intType(), NullInt64{}, false},
-		// INT64 ARRAY
-		{listProto(intProto(91), nullProto(), intProto(87)), listType(intType()), []NullInt64{{91, true}, {}, {87, true}}, false},
-		{nullProto(), listType(intType()), []NullInt64(nil), false},
-		// BOOL
-		{boolProto(true), boolType(), true, false},
-		{nullProto(), boolType(), true, true},
-		{boolProto(true), boolType(), NullBool{true, true}, false},
-		{nullProto(), boolType(), NullBool{}, false},
-		// BOOL ARRAY
-		{listProto(boolProto(true), boolProto(false), nullProto()), listType(boolType()), []NullBool{{true, true}, {false, true}, {}}, false},
-		{nullProto(), listType(boolType()), []NullBool(nil), false},
-		// FLOAT64
-		{floatProto(3.14), floatType(), 3.14, false},
-		{nullProto(), floatType(), 0.00, true},
-		{floatProto(3.14), floatType(), NullFloat64{3.14, true}, false},
-		{nullProto(), floatType(), NullFloat64{}, false},
-		// FLOAT64 ARRAY
-		{
-			listProto(floatProto(math.Inf(1)), floatProto(math.Inf(-1)), nullProto(), floatProto(3.1)),
-			listType(floatType()),
-			[]NullFloat64{{math.Inf(1), true}, {math.Inf(-1), true}, {}, {3.1, true}},
-			false,
-		},
-		{nullProto(), listType(floatType()), []NullFloat64(nil), false},
-		// TIMESTAMP
-		{timeProto(t1), timeType(), t1, false},
-		{timeProto(t1), timeType(), NullTime{t1, true}, false},
-		{nullProto(), timeType(), NullTime{}, false},
-		// TIMESTAMP ARRAY
-		{listProto(timeProto(t1), timeProto(t2), timeProto(t3), nullProto()), listType(timeType()), []NullTime{{t1, true}, {t2, true}, {t3, true}, {}}, false},
-		{nullProto(), listType(timeType()), []NullTime(nil), false},
-		// DATE
-		{dateProto(d1), dateType(), d1, false},
-		{dateProto(d1), dateType(), NullDate{d1, true}, false},
-		{nullProto(), dateType(), NullDate{}, false},
-		// DATE ARRAY
-		{listProto(dateProto(d1), dateProto(d2), nullProto()), listType(dateType()), []NullDate{{d1, true}, {d2, true}, {}}, false},
-		{nullProto(), listType(dateType()), []NullDate(nil), false},
-		// STRUCT ARRAY
-		// STRUCT schema is equal to the following Go struct:
-		// type s struct {
-		//     Col1 NullInt64
-		//     Col2 []struct {
-		//         SubCol1 float64
-		//         SubCol2 string
-		//     }
-		// }
-		{
-			in: listProto(
-				listProto(
-					intProto(3),
-					listProto(
-						listProto(floatProto(3.14), stringProto("this")),
-						listProto(floatProto(0.57), stringProto("siht")),
-					),
-				),
-				listProto(
-					nullProto(),
-					nullProto(),
-				),
-				nullProto(),
-			),
-			t: listType(
-				structType(
-					mkField("Col1", intType()),
-					mkField(
-						"Col2",
-						listType(
-							structType(
-								mkField("SubCol1", floatType()),
-								mkField("SubCol2", stringType()),
-							),
-						),
-					),
-				),
-			),
-			want: []NullRow{
-				{
-					Row: Row{
-						fields: []*sppb.StructType_Field{
-							mkField("Col1", intType()),
-							mkField(
-								"Col2",
-								listType(
-									structType(
-										mkField("SubCol1", floatType()),
-										mkField("SubCol2", stringType()),
-									),
-								),
-							),
-						},
-						vals: []*proto3.Value{
-							intProto(3),
-							listProto(
-								listProto(floatProto(3.14), stringProto("this")),
-								listProto(floatProto(0.57), stringProto("siht")),
-							),
-						},
-					},
-					Valid: true,
-				},
-				{
-					Row: Row{
-						fields: []*sppb.StructType_Field{
-							mkField("Col1", intType()),
-							mkField(
-								"Col2",
-								listType(
-									structType(
-										mkField("SubCol1", floatType()),
-										mkField("SubCol2", stringType()),
-									),
-								),
-							),
-						},
-						vals: []*proto3.Value{
-							nullProto(),
-							nullProto(),
-						},
-					},
-					Valid: true,
-				},
-				{},
-			},
-			fail: false,
-		},
-		{
-			in: listProto(
-				listProto(
-					intProto(3),
-					listProto(
-						listProto(floatProto(3.14), stringProto("this")),
-						listProto(floatProto(0.57), stringProto("siht")),
-					),
-				),
-				listProto(
-					nullProto(),
-					nullProto(),
-				),
-				nullProto(),
-			),
-			t: listType(
-				structType(
-					mkField("Col1", intType()),
-					mkField(
-						"Col2",
-						listType(
-							structType(
-								mkField("SubCol1", floatType()),
-								mkField("SubCol2", stringType()),
-							),
-						),
-					),
-				),
-			),
-			want: []*struct {
-				Col1      NullInt64
-				StructCol []*struct {
-					SubCol1 NullFloat64
-					SubCol2 string
-				} `spanner:"Col2"`
-			}{
-				{
-					Col1: NullInt64{3, true},
-					StructCol: []*struct {
-						SubCol1 NullFloat64
-						SubCol2 string
-					}{
-						{
-							SubCol1: NullFloat64{3.14, true},
-							SubCol2: "this",
-						},
-						{
-							SubCol1: NullFloat64{0.57, true},
-							SubCol2: "siht",
-						},
-					},
-				},
-				{
-					Col1: NullInt64{},
-					StructCol: []*struct {
-						SubCol1 NullFloat64
-						SubCol2 string
-					}(nil),
-				},
-				nil,
-			},
-			fail: false,
-		},
-		// GenericColumnValue
-		{stringProto("abc"), stringType(), GenericColumnValue{stringType(), stringProto("abc")}, false},
-		{nullProto(), stringType(), GenericColumnValue{stringType(), nullProto()}, false},
-		// not actually valid (stringProto inside int list), but demonstrates pass-through.
-		{
-			in: listProto(intProto(5), nullProto(), stringProto("bcd")),
-			t:  listType(intType()),
-			want: GenericColumnValue{
-				Type:  listType(intType()),
-				Value: listProto(intProto(5), nullProto(), stringProto("bcd")),
-			},
-			fail: false,
-		},
-	} {
-		gotp := reflect.New(reflect.TypeOf(test.want))
-		if err := decodeValue(test.in, test.t, gotp.Interface()); err != nil {
-			if !test.fail {
-				t.Errorf("%d: cannot decode %v(%v): %v", i, test.in, test.t, err)
-			}
-			continue
-		}
-		if test.fail {
-			t.Errorf("%d: decoding %v(%v) succeeds unexpectedly, want error", i, test.in, test.t)
-			continue
-		}
-		got := reflect.Indirect(gotp).Interface()
-		if !reflect.DeepEqual(got, test.want) {
-			t.Errorf("%d: unexpected decoding result - got %v, want %v", i, got, test.want)
-			continue
-		}
-	}
-}
-
-// Test error cases for decodeValue.
-func TestDecodeValueErrors(t *testing.T) {
-	for i, test := range []struct {
-		in *proto3.Value
-		t  *sppb.Type
-		v  interface{}
-	}{
-		{nullProto(), stringType(), nil},
-		{nullProto(), stringType(), 1},
-	} {
-		err := decodeValue(test.in, test.t, test.v)
-		if err == nil {
-			t.Errorf("#%d: want error, got nil", i)
-		}
-	}
-}
-
-// Test NaN encoding/decoding.
-func TestNaN(t *testing.T) {
-	// Decode NaN value.
-	f := 0.0
-	nf := NullFloat64{}
-	// To float64
-	if err := decodeValue(floatProto(math.NaN()), floatType(), &f); err != nil {
-		t.Errorf("decodeValue returns %q for %v, want nil", err, floatProto(math.NaN()))
-	}
-	if !math.IsNaN(f) {
-		t.Errorf("f = %v, want %v", f, math.NaN())
-	}
-	// To NullFloat64
-	if err := decodeValue(floatProto(math.NaN()), floatType(), &nf); err != nil {
-		t.Errorf("decodeValue returns %q for %v, want nil", err, floatProto(math.NaN()))
-	}
-	if !math.IsNaN(nf.Float64) || !nf.Valid {
-		t.Errorf("f = %v, want %v", f, NullFloat64{math.NaN(), true})
-	}
-	// Encode NaN value
-	// From float64
-	v, _, err := encodeValue(math.NaN())
-	if err != nil {
-		t.Errorf("encodeValue returns %q for NaN, want nil", err)
-	}
-	x, ok := v.GetKind().(*proto3.Value_NumberValue)
-	if !ok {
-		t.Errorf("incorrect type for v.GetKind(): %T, want *proto3.Value_NumberValue", v.GetKind())
-	}
-	if !math.IsNaN(x.NumberValue) {
-		t.Errorf("x.NumberValue = %v, want %v", x.NumberValue, math.NaN())
-	}
-	// From NullFloat64
-	v, _, err = encodeValue(NullFloat64{math.NaN(), true})
-	if err != nil {
-		t.Errorf("encodeValue returns %q for NaN, want nil", err)
-	}
-	x, ok = v.GetKind().(*proto3.Value_NumberValue)
-	if !ok {
-		t.Errorf("incorrect type for v.GetKind(): %T, want *proto3.Value_NumberValue", v.GetKind())
-	}
-	if !math.IsNaN(x.NumberValue) {
-		t.Errorf("x.NumberValue = %v, want %v", x.NumberValue, math.NaN())
-	}
-}
-
-func TestGenericColumnValue(t *testing.T) {
-	for _, test := range []struct {
-		in   GenericColumnValue
-		want interface{}
-		fail bool
-	}{
-		{GenericColumnValue{stringType(), stringProto("abc")}, "abc", false},
-		{GenericColumnValue{stringType(), stringProto("abc")}, 5, true},
-		{GenericColumnValue{listType(intType()), listProto(intProto(91), nullProto(), intProto(87))}, []NullInt64{{91, true}, {}, {87, true}}, false},
-		{GenericColumnValue{intType(), intProto(42)}, GenericColumnValue{intType(), intProto(42)}, false}, // trippy! :-)
-	} {
-		// We take a copy and mutate because we're paranoid about immutability.
-		inCopy := GenericColumnValue{
-			Type:  proto.Clone(test.in.Type).(*sppb.Type),
-			Value: proto.Clone(test.in.Value).(*proto3.Value),
-		}
-		gotp := reflect.New(reflect.TypeOf(test.want))
-		if err := inCopy.Decode(gotp.Interface()); err != nil {
-			if !test.fail {
-				t.Errorf("cannot decode %v to %v: %v", test.in, test.want, err)
-			}
-			continue
-		}
-		if test.fail {
-			t.Errorf("decoding %v to %v succeeds unexpectedly", test.in, test.want)
-		}
-		// mutations to inCopy should be invisible to gotp.
-		inCopy.Type.Code = sppb.TypeCode_TIMESTAMP
-		inCopy.Value.Kind = &proto3.Value_NumberValue{NumberValue: 999}
-		got := reflect.Indirect(gotp).Interface()
-		if !reflect.DeepEqual(got, test.want) {
-			t.Errorf("unexpected decode result - got %v, want %v", got, test.want)
-		}
-
-		// Test we can go backwards as well.
-		v, err := newGenericColumnValue(test.want)
-		if err != nil {
-			t.Errorf("NewGenericColumnValue failed: %v", err)
-			continue
-		}
-		if !reflect.DeepEqual(*v, test.in) {
-			t.Errorf("unexpected encode result - got %v, want %v", v, test.in)
-		}
-		// If want is a GenericColumnValue, mutate its underlying value to validate
-		// we have taken a deep copy.
-		if gcv, ok := test.want.(GenericColumnValue); ok {
-			gcv.Type.Code = sppb.TypeCode_TIMESTAMP
-			gcv.Value.Kind = &proto3.Value_NumberValue{NumberValue: 999}
-			if !reflect.DeepEqual(*v, test.in) {
-				t.Errorf("expected deep copy - got %v, want %v", v, test.in)
-			}
-		}
-	}
-}
-
-func runBench(b *testing.B, size int, f func(a []int) (*proto3.Value, *sppb.Type, error)) {
-	a := make([]int, size)
-	for i := 0; i < b.N; i++ {
-		f(a)
-	}
-}
-
-func BenchmarkEncodeIntArrayOrig1(b *testing.B) {
-	runBench(b, 1, encodeIntArrayOrig)
-}
-
-func BenchmarkEncodeIntArrayOrig10(b *testing.B) {
-	runBench(b, 10, encodeIntArrayOrig)
-}
-
-func BenchmarkEncodeIntArrayOrig100(b *testing.B) {
-	runBench(b, 100, encodeIntArrayOrig)
-}
-
-func BenchmarkEncodeIntArrayOrig1000(b *testing.B) {
-	runBench(b, 1000, encodeIntArrayOrig)
-}
-
-func BenchmarkEncodeIntArrayFunc1(b *testing.B) {
-	runBench(b, 1, encodeIntArrayFunc)
-}
-
-func BenchmarkEncodeIntArrayFunc10(b *testing.B) {
-	runBench(b, 10, encodeIntArrayFunc)
-}
-
-func BenchmarkEncodeIntArrayFunc100(b *testing.B) {
-	runBench(b, 100, encodeIntArrayFunc)
-}
-
-func BenchmarkEncodeIntArrayFunc1000(b *testing.B) {
-	runBench(b, 1000, encodeIntArrayFunc)
-}
-
-func BenchmarkEncodeIntArrayReflect1(b *testing.B) {
-	runBench(b, 1, encodeIntArrayReflect)
-}
-
-func BenchmarkEncodeIntArrayReflect10(b *testing.B) {
-	runBench(b, 10, encodeIntArrayReflect)
-}
-
-func BenchmarkEncodeIntArrayReflect100(b *testing.B) {
-	runBench(b, 100, encodeIntArrayReflect)
-}
-
-func BenchmarkEncodeIntArrayReflect1000(b *testing.B) {
-	runBench(b, 1000, encodeIntArrayReflect)
-}
-
-func encodeIntArrayOrig(a []int) (*proto3.Value, *sppb.Type, error) {
-	vs := make([]*proto3.Value, len(a))
-	var err error
-	for i := range a {
-		vs[i], _, err = encodeValue(a[i])
-		if err != nil {
-			return nil, nil, err
-		}
-	}
-	return listProto(vs...), listType(intType()), nil
-}
-
-func encodeIntArrayFunc(a []int) (*proto3.Value, *sppb.Type, error) {
-	v, err := encodeArray(len(a), func(i int) interface{} { return a[i] })
-	if err != nil {
-		return nil, nil, err
-	}
-	return v, listType(intType()), nil
-}
-
-func encodeIntArrayReflect(a []int) (*proto3.Value, *sppb.Type, error) {
-	v, err := encodeArrayReflect(a)
-	if err != nil {
-		return nil, nil, err
-	}
-	return v, listType(intType()), nil
-}
-
-func encodeArrayReflect(a interface{}) (*proto3.Value, error) {
-	va := reflect.ValueOf(a)
-	len := va.Len()
-	vs := make([]*proto3.Value, len)
-	var err error
-	for i := 0; i < len; i++ {
-		vs[i], _, err = encodeValue(va.Index(i).Interface())
-		if err != nil {
-			return nil, err
-		}
-	}
-	return listProto(vs...), nil
-}