dashboard/app: test coverage /file link

1. Init coveragedb client once and propagate it through context to enable mocking.
2. Always init coverage handlers. It simplifies testing.
3. Read webGit and coveragedb client from ctx to make it mockable.
4. Use int for file line number and int64 for merged coverage.
5. Add tests.

1 files changed, 18 insertions, 23 deletions

diff --git a/pkg/coveragedb/coveragedb.go b/pkg/coveragedb/coveragedb.go
index 22e84d8eb..0692bc131 100644
--- a/pkg/coveragedb/coveragedb.go
+++ b/pkg/coveragedb/coveragedb.go
@@ -9,7 +9,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"os"
 	"sync/atomic"
 	"time"
 
@@ -74,6 +73,9 @@ type MergedCoverageRecord struct {
 
 func SaveMergeResult(ctx context.Context, client spannerclient.SpannerClient, descr *HistoryRecord, dec *json.Decoder,
 	sss []*subsystem.Subsystem) (int, error) {
+	if client == nil {
+		return 0, fmt.Errorf("nil spannerclient")
+	}
 	var rowsCreated int
 	ssMatcher := subsystem.MakePathMatcher(sss)
 	ssCache := make(map[string][]string)
@@ -117,7 +119,7 @@ func SaveMergeResult(ctx context.Context, client spannerclient.SpannerClient, de
 	return rowsCreated, nil
 }
 
-type linesCoverage struct {
+type LinesCoverage struct {
 	LinesInstrumented []int64
 	HitCounts         []int64
 }
@@ -147,15 +149,9 @@ where
 	}
 }
 
-func ReadLinesHitCount(ctx context.Context, ns, commit, file, manager string, tp TimePeriod,
+func ReadLinesHitCount(ctx context.Context, client spannerclient.SpannerClient,
+	ns, commit, file, manager string, tp TimePeriod,
 ) ([]int64, []int64, error) {
-	projectID := os.Getenv("GOOGLE_CLOUD_PROJECT")
-	client, err := spannerclient.NewClient(ctx, projectID)
-	if err != nil {
-		return nil, nil, fmt.Errorf("spanner.NewClient: %w", err)
-	}
-	defer client.Close()
-
 	stmt := linesCoverageStmt(ns, file, commit, manager, tp)
 	iter := client.Single().Query(ctx, stmt)
 	defer iter.Stop()
@@ -167,10 +163,13 @@ func ReadLinesHitCount(ctx context.Context, ns, commit, file, manager string, tp
 	if err != nil {
 		return nil, nil, fmt.Errorf("iter.Next: %w", err)
 	}
-	var r linesCoverage
+	var r LinesCoverage
 	if err = row.ToStruct(&r); err != nil {
 		return nil, nil, fmt.Errorf("failed to row.ToStruct() spanner DB: %w", err)
 	}
+	if _, err := iter.Next(); err != iterator.Done {
+		return nil, nil, fmt.Errorf("more than 1 line is available")
+	}
 	return r.LinesInstrumented, r.HitCounts, nil
 }
 
@@ -230,13 +229,11 @@ func fileSubsystems(filePath string, ssMatcher *subsystem.PathMatcher, ssCache m
 	return sss
 }
 
-func NsDataMerged(ctx context.Context, projectID, ns string) ([]TimePeriod, []int64, error) {
-	client, err := spannerclient.NewClient(ctx, projectID)
-	if err != nil {
-		return nil, nil, fmt.Errorf("spanner.NewClient() failed: %s", err.Error())
+func NsDataMerged(ctx context.Context, client spannerclient.SpannerClient, ns string,
+) ([]TimePeriod, []int64, error) {
+	if client == nil {
+		return nil, nil, fmt.Errorf("nil spannerclient")
 	}
-	defer client.Close()
-
 	stmt := spanner.Statement{
 		SQL: `
 			select
@@ -285,13 +282,11 @@ func NsDataMerged(ctx context.Context, projectID, ns string) ([]TimePeriod, []in
 // Note that in case of an error during batch deletion, some files may be deleted but not counted in the total.
 //
 // Returns the number of orphaned file entries successfully deleted.
-func DeleteGarbage(ctx context.Context) (int64, error) {
+func DeleteGarbage(ctx context.Context, client spannerclient.SpannerClient) (int64, error) {
 	batchSize := 10_000
-	client, err := spannerclient.NewClient(ctx, os.Getenv("GOOGLE_CLOUD_PROJECT"))
-	if err != nil {
-		return 0, fmt.Errorf("coveragedb.NewClient: %w", err)
+	if client == nil {
+		return 0, fmt.Errorf("nil spannerclient")
 	}
-	defer client.Close()
 
 	iter := client.Single().Query(ctx, spanner.Statement{
 		SQL: `SELECT session, filepath
@@ -328,7 +323,7 @@ func DeleteGarbage(ctx context.Context) (int64, error) {
 		}
 	}
 	goSpannerDelete(ctx, batch, eg, client, &totalDeleted)
-	if err = eg.Wait(); err != nil {
+	if err := eg.Wait(); err != nil {
 		return 0, fmt.Errorf("spanner.Delete: %w", err)
 	}
 	return totalDeleted.Load(), nil