go.mod: vendor golangci-lint

5 files changed, 662 insertions, 0 deletions

diff --git a/vendor/github.com/golangci/revgrep/.gitignore b/vendor/github.com/golangci/revgrep/.gitignore
new file mode 100644
index 000000000..0540fe2ca
--- /dev/null
+++ b/vendor/github.com/golangci/revgrep/.gitignore
@@ -0,0 +1 @@
+testdata/git
diff --git a/vendor/github.com/golangci/revgrep/.travis.yml b/vendor/github.com/golangci/revgrep/.travis.yml
new file mode 100644
index 000000000..d16d8b5bd
--- /dev/null
+++ b/vendor/github.com/golangci/revgrep/.travis.yml
@@ -0,0 +1,7 @@
+language: go
+before_install:
+    - go get github.com/mattn/goveralls
+    - go get golang.org/x/tools/cmd/cover
+script:
+    - $HOME/gopath/bin/goveralls -service=travis-ci
+
diff --git a/vendor/github.com/golangci/revgrep/LICENSE b/vendor/github.com/golangci/revgrep/LICENSE
new file mode 100644
index 000000000..8dada3eda
--- /dev/null
+++ b/vendor/github.com/golangci/revgrep/LICENSE
@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
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+      represent, as a whole, an original work of authorship. For the purposes
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+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
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+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
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+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
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+   See the License for the specific language governing permissions and
+   limitations under the License.
diff --git a/vendor/github.com/golangci/revgrep/README.md b/vendor/github.com/golangci/revgrep/README.md
new file mode 100644
index 000000000..31faefee9
--- /dev/null
+++ b/vendor/github.com/golangci/revgrep/README.md
@@ -0,0 +1,58 @@
+# Overview
+
+[![Build Status](https://travis-ci.org/bradleyfalzon/revgrep.svg?branch=master)](https://travis-ci.org/bradleyfalzon/revgrep) [![Coverage
+Status](https://coveralls.io/repos/github/bradleyfalzon/revgrep/badge.svg?branch=master)](https://coveralls.io/github/bradleyfalzon/revgrep?branch=master) [![GoDoc](https://godoc.org/github.com/bradleyfalzon/revgrep?status.svg)](https://godoc.org/github.com/bradleyfalzon/revgrep)
+
+`revgrep` is a CLI tool used to filter static analysis tools to only lines changed based on a commit reference.
+
+# Install
+
+```bash
+go get -u github.com/bradleyfalzon/revgrep/...
+```
+
+# Usage
+
+In the scenario below, a change was made causing a warning in `go vet` on line 5, but `go vet` will show all warnings.
+Using `revgrep`, you can show only warnings for lines of code that have been changed (in this case, hiding line 6).
+
+```bash
+[user@host dir (master)]$ go vet
+main.go:5: missing argument for Sprintf("%s"): format reads arg 1, have only 0 args
+main.go:6: missing argument for Sprintf("%s"): format reads arg 1, have only 0 args
+[user@host dir (master)]$ go vet |& revgrep
+main.go:5: missing argument for Sprintf("%s"): format reads arg 1, have only 0 args
+```
+
+`|&` is shown above as many static analysis programs write to `stderr`, not `stdout`, `|&` combines both `stderr` and
+`stdout`. It could also be achieved with `go vet 2>&1 | revgrep`.
+
+`revgrep` CLI tool will return an exit status of 1 if any issues match, else it will return 0. Consider using
+`${PIPESTATUS[0]}` for the exit status of the `go vet` command in the above example.
+
+```
+Usage: revgrep [options] [from-rev] [to-rev]
+
+from-rev filters issues to lines changed since (and including) this revision
+  to-rev filters issues to lines changed since (and including) this revision, requires <from-rev>
+
+  If no revisions are given, and there are unstaged changes or untracked files, only those changes are shown
+  If no revisions are given, and there are no unstaged changes or untracked files, only changes in HEAD~ are shown
+  If from-rev is given and to-rev is not, only changes between from-rev and HEAD are shown.
+
+    -d    Show debug output
+      -regexp string
+              Regexp to match path, line number, optional column number, and message
+```
+
+# Other Examples
+
+Issues between branches:
+```bash
+[user@host dir (feature/branch)]$ go vet |& revgrep master
+```
+
+Issues since last push:
+```bash
+[user@host dir (master)]$ go vet |& revgrep origin/master
+```
diff --git a/vendor/github.com/golangci/revgrep/revgrep.go b/vendor/github.com/golangci/revgrep/revgrep.go
new file mode 100644
index 000000000..1a56dcf4e
--- /dev/null
+++ b/vendor/github.com/golangci/revgrep/revgrep.go
@@ -0,0 +1,395 @@
+package revgrep
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+// Checker provides APIs to filter static analysis tools to specific commits,
+// such as showing only issues since last commit.
+type Checker struct {
+	// Patch file (unified) to read to detect lines being changed, if nil revgrep
+	// will attempt to detect the VCS and generate an appropriate patch. Auto
+	// detection will search for uncommitted changes first, if none found, will
+	// generate a patch from last committed change. File paths within patches
+	// must be relative to current working directory.
+	Patch io.Reader
+	// NewFiles is a list of file names (with absolute paths) where the entire
+	// contents of the file is new.
+	NewFiles []string
+	// Debug sets the debug writer for additional output.
+	Debug io.Writer
+	// RevisionFrom check revision starting at, leave blank for auto detection
+	// ignored if patch is set.
+	RevisionFrom string
+	// RevisionTo checks revision finishing at, leave blank for auto detection
+	// ignored if patch is set.
+	RevisionTo string
+	// Regexp to match path, line number, optional column number, and message.
+	Regexp string
+	// AbsPath is used to make an absolute path of an issue's filename to be
+	// relative in order to match patch file. If not set, current working
+	// directory is used.
+	AbsPath string
+
+	// Calculated changes for next calls to IsNewIssue
+	changes map[string][]pos
+}
+
+// Issue contains metadata about an issue found.
+type Issue struct {
+	// File is the name of the file as it appeared from the patch.
+	File string
+	// LineNo is the line number of the file.
+	LineNo int
+	// ColNo is the column number or 0 if none could be parsed.
+	ColNo int
+	// HunkPos is position from file's first @@, for new files this will be the
+	// line number.
+	//
+	// See also: https://developer.github.com/v3/pulls/comments/#create-a-comment
+	HunkPos int
+	// Issue text as it appeared from the tool.
+	Issue string
+	// Message is the issue without file name, line number and column number.
+	Message string
+}
+
+func (c *Checker) preparePatch() error {
+	// Check if patch is supplied, if not, retrieve from VCS
+	if c.Patch == nil {
+		var err error
+		c.Patch, c.NewFiles, err = GitPatch(c.RevisionFrom, c.RevisionTo)
+		if err != nil {
+			return fmt.Errorf("could not read git repo: %s", err)
+		}
+		if c.Patch == nil {
+			return errors.New("no version control repository found")
+		}
+	}
+
+	return nil
+}
+
+type InputIssue interface {
+	FilePath() string
+	Line() int
+}
+
+type simpleInputIssue struct {
+	filePath   string
+	lineNumber int
+}
+
+func (i simpleInputIssue) FilePath() string {
+	return i.filePath
+}
+
+func (i simpleInputIssue) Line() int {
+	return i.lineNumber
+}
+
+func (c *Checker) Prepare() error {
+	returnErr := c.preparePatch()
+	c.changes = c.linesChanged()
+	return returnErr
+}
+
+func (c Checker) IsNewIssue(i InputIssue) (hunkPos int, isNew bool) {
+	fchanges, ok := c.changes[i.FilePath()]
+	if !ok { // file wasn't changed
+		return 0, false
+	}
+
+	var (
+		fpos    pos
+		changed bool
+	)
+	// found file, see if lines matched
+	for _, pos := range fchanges {
+		if pos.lineNo == int(i.Line()) {
+			fpos = pos
+			changed = true
+			break
+		}
+	}
+
+	if changed || fchanges == nil {
+		// either file changed or it's a new file
+		hunkPos := fpos.lineNo
+		if changed { // existing file changed
+			hunkPos = fpos.hunkPos
+		}
+
+		return hunkPos, true
+	}
+
+	return 0, false
+}
+
+// Check scans reader and writes any lines to writer that have been added in
+// Checker.Patch.
+//
+// Returns issues written to writer when no error occurs.
+//
+// If no VCS could be found or other VCS errors occur, all issues are written
+// to writer and an error is returned.
+//
+// File paths in reader must be relative to current working directory or
+// absolute.
+func (c Checker) Check(reader io.Reader, writer io.Writer) (issues []Issue, err error) {
+	returnErr := c.Prepare()
+	writeAll := returnErr != nil
+
+	// file.go:lineNo:colNo:message
+	// colNo is optional, strip spaces before message
+	lineRE := regexp.MustCompile(`(.*?\.go):([0-9]+):([0-9]+)?:?\s*(.*)`)
+	if c.Regexp != "" {
+		lineRE, err = regexp.Compile(c.Regexp)
+		if err != nil {
+			return nil, fmt.Errorf("could not parse regexp: %v", err)
+		}
+	}
+
+	// TODO consider lazy loading this, if there's nothing in stdin, no point
+	// checking for recent changes
+	c.debugf("lines changed: %+v", c.changes)
+
+	absPath := c.AbsPath
+	if absPath == "" {
+		absPath, err = os.Getwd()
+		if err != nil {
+			returnErr = fmt.Errorf("could not get current working directory: %s", err)
+		}
+	}
+
+	// Scan each line in reader and only write those lines if lines changed
+	scanner := bufio.NewScanner(reader)
+	for scanner.Scan() {
+		line := lineRE.FindSubmatch(scanner.Bytes())
+		if line == nil {
+			c.debugf("cannot parse file+line number: %s", scanner.Text())
+			continue
+		}
+
+		if writeAll {
+			fmt.Fprintln(writer, scanner.Text())
+			continue
+		}
+
+		// Make absolute path names relative
+		path := string(line[1])
+		if rel, err := filepath.Rel(absPath, path); err == nil {
+			c.debugf("rewrote path from %q to %q (absPath: %q)", path, rel, absPath)
+			path = rel
+		}
+
+		// Parse line number
+		lno, err := strconv.ParseUint(string(line[2]), 10, 64)
+		if err != nil {
+			c.debugf("cannot parse line number: %q", scanner.Text())
+			continue
+		}
+
+		// Parse optional column number
+		var cno uint64
+		if len(line[3]) > 0 {
+			cno, err = strconv.ParseUint(string(line[3]), 10, 64)
+			if err != nil {
+				c.debugf("cannot parse column number: %q", scanner.Text())
+				// Ignore this error and continue
+			}
+		}
+
+		// Extract message
+		msg := string(line[4])
+
+		c.debugf("path: %q, lineNo: %v, colNo: %v, msg: %q", path, lno, cno, msg)
+		i := simpleInputIssue{
+			filePath:   path,
+			lineNumber: int(lno),
+		}
+		hunkPos, changed := c.IsNewIssue(i)
+		if changed {
+			issue := Issue{
+				File:    path,
+				LineNo:  int(lno),
+				ColNo:   int(cno),
+				HunkPos: hunkPos,
+				Issue:   scanner.Text(),
+				Message: msg,
+			}
+			issues = append(issues, issue)
+			fmt.Fprintln(writer, scanner.Text())
+		} else {
+			c.debugf("unchanged: %s", scanner.Text())
+		}
+	}
+	if err := scanner.Err(); err != nil {
+		returnErr = fmt.Errorf("error reading standard input: %s", err)
+	}
+	return issues, returnErr
+}
+
+func (c Checker) debugf(format string, s ...interface{}) {
+	if c.Debug != nil {
+		fmt.Fprint(c.Debug, "DEBUG: ")
+		fmt.Fprintf(c.Debug, format+"\n", s...)
+	}
+}
+
+type pos struct {
+	lineNo  int // line number
+	hunkPos int // position relative to first @@ in file
+}
+
+// linesChanges returns a map of file names to line numbers being changed.
+// If key is nil, the file has been recently added, else it contains a slice
+// of positions that have been added.
+func (c Checker) linesChanged() map[string][]pos {
+	type state struct {
+		file    string
+		lineNo  int   // current line number within chunk
+		hunkPos int   // current line count since first @@ in file
+		changes []pos // position of changes
+	}
+
+	var (
+		s       state
+		changes = make(map[string][]pos)
+	)
+
+	for _, file := range c.NewFiles {
+		changes[file] = nil
+	}
+
+	if c.Patch == nil {
+		return changes
+	}
+
+	scanner := bufio.NewScanner(c.Patch)
+	for scanner.Scan() {
+		line := scanner.Text() // TODO scanner.Bytes()
+		c.debugf(line)
+		s.lineNo++
+		s.hunkPos++
+		switch {
+		case strings.HasPrefix(line, "+++ ") && len(line) > 4:
+			if s.changes != nil {
+				// record the last state
+				changes[s.file] = s.changes
+			}
+			// 6 removes "+++ b/"
+			s = state{file: line[6:], hunkPos: -1, changes: []pos{}}
+		case strings.HasPrefix(line, "@@ "):
+			//      @@ -1 +2,4 @@
+			// chdr ^^^^^^^^^^^^^
+			// ahdr       ^^^^
+			// cstart      ^
+			chdr := strings.Split(line, " ")
+			ahdr := strings.Split(chdr[2], ",")
+			// [1:] to remove leading plus
+			cstart, err := strconv.ParseUint(ahdr[0][1:], 10, 64)
+			if err != nil {
+				panic(err)
+			}
+			s.lineNo = int(cstart) - 1 // -1 as cstart is the next line number
+		case strings.HasPrefix(line, "-"):
+			s.lineNo--
+		case strings.HasPrefix(line, "+"):
+			s.changes = append(s.changes, pos{lineNo: s.lineNo, hunkPos: s.hunkPos})
+		}
+
+	}
+	if err := scanner.Err(); err != nil {
+		fmt.Fprintln(os.Stderr, "reading standard input:", err)
+	}
+	// record the last state
+	changes[s.file] = s.changes
+
+	return changes
+}
+
+// GitPatch returns a patch from a git repository, if no git repository was
+// was found and no errors occurred, nil is returned, else an error is returned
+// revisionFrom and revisionTo defines the git diff parameters, if left blank
+// and there are unstaged changes or untracked files, only those will be returned
+// else only check changes since HEAD~. If revisionFrom is set but revisionTo
+// is not, untracked files will be included, to exclude untracked files set
+// revisionTo to HEAD~. It's incorrect to specify revisionTo without a
+// revisionFrom.
+func GitPatch(revisionFrom, revisionTo string) (io.Reader, []string, error) {
+	var patch bytes.Buffer
+
+	// check if git repo exists
+	if err := exec.Command("git", "status").Run(); err != nil {
+		// don't return an error, we assume the error is not repo exists
+		return nil, nil, nil
+	}
+
+	// make a patch for untracked files
+	var newFiles []string
+	ls, err := exec.Command("git", "ls-files", "-o").CombinedOutput()
+	if err != nil {
+		return nil, nil, fmt.Errorf("error executing git ls-files: %s", err)
+	}
+	for _, file := range bytes.Split(ls, []byte{'\n'}) {
+		if len(file) == 0 || bytes.HasSuffix(file, []byte{'/'}) {
+			// ls-files was sometimes showing directories when they were ignored
+			// I couldn't create a test case for this as I couldn't reproduce correctly
+			// for the moment, just exclude files with trailing /
+			continue
+		}
+		newFiles = append(newFiles, string(file))
+	}
+
+	if revisionFrom != "" {
+		cmd := exec.Command("git", "diff", "--relative", revisionFrom)
+		if revisionTo != "" {
+			cmd.Args = append(cmd.Args, revisionTo)
+		}
+		cmd.Stdout = &patch
+		if err := cmd.Run(); err != nil {
+			return nil, nil, fmt.Errorf("error executing git diff %q %q: %s", revisionFrom, revisionTo, err)
+		}
+
+		if revisionTo == "" {
+			return &patch, newFiles, nil
+		}
+		return &patch, nil, nil
+	}
+
+	// make a patch for unstaged changes
+	// use --no-prefix to remove b/ given: +++ b/main.go
+	cmd := exec.Command("git", "diff", "--relative")
+	cmd.Stdout = &patch
+	if err := cmd.Run(); err != nil {
+		return nil, nil, fmt.Errorf("error executing git diff: %s", err)
+	}
+	unstaged := patch.Len() > 0
+
+	// If there's unstaged changes OR untracked changes (or both), then this is
+	// a suitable patch
+	if unstaged || newFiles != nil {
+		return &patch, newFiles, nil
+	}
+
+	// check for changes in recent commit
+
+	cmd = exec.Command("git", "diff", "--relative", "HEAD~")
+	cmd.Stdout = &patch
+	if err := cmd.Run(); err != nil {
+		return nil, nil, fmt.Errorf("error executing git diff HEAD~: %s", err)
+	}
+
+	return &patch, nil, nil
+}