go.mod: vendor golangci-lint

1 files changed, 625 insertions, 0 deletions

diff --git a/vendor/github.com/sourcegraph/go-diff/diff/parse.go b/vendor/github.com/sourcegraph/go-diff/diff/parse.go
new file mode 100644
index 000000000..1e77df48f
--- /dev/null
+++ b/vendor/github.com/sourcegraph/go-diff/diff/parse.go
@@ -0,0 +1,625 @@
+package diff
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"strings"
+	"time"
+
+	"sourcegraph.com/sqs/pbtypes"
+)
+
+// ParseMultiFileDiff parses a multi-file unified diff. It returns an error if parsing failed as a whole, but does its
+// best to parse as many files in the case of per-file errors. In the case of non-fatal per-file errors, the error
+// return value is null and the Errs field in the returned MultiFileDiff is set.
+func ParseMultiFileDiff(diff []byte) ([]*FileDiff, error) {
+	return NewMultiFileDiffReader(bytes.NewReader(diff)).ReadAllFiles()
+}
+
+// NewMultiFileDiffReader returns a new MultiFileDiffReader that reads
+// a multi-file unified diff from r.
+func NewMultiFileDiffReader(r io.Reader) *MultiFileDiffReader {
+	return &MultiFileDiffReader{reader: bufio.NewReader(r)}
+}
+
+// MultiFileDiffReader reads a multi-file unified diff.
+type MultiFileDiffReader struct {
+	line   int
+	offset int64
+	reader *bufio.Reader
+
+	// TODO(sqs): line and offset tracking in multi-file diffs is broken; add tests and fix
+
+	// nextFileFirstLine is a line that was read by a HunksReader that
+	// was how it determined the hunk was complete. But to determine
+	// that, it needed to read the first line of the next file. We
+	// store nextFileFirstLine so we can "give the first line back" to
+	// the next file.
+	nextFileFirstLine []byte
+}
+
+// ReadFile reads the next file unified diff (including headers and
+// all hunks) from r. If there are no more files in the diff, it
+// returns error io.EOF.
+func (r *MultiFileDiffReader) ReadFile() (*FileDiff, error) {
+	fr := &FileDiffReader{
+		line:           r.line,
+		offset:         r.offset,
+		reader:         r.reader,
+		fileHeaderLine: r.nextFileFirstLine,
+	}
+	r.nextFileFirstLine = nil
+
+	fd, err := fr.ReadAllHeaders()
+	if err != nil {
+		switch e := err.(type) {
+		case *ParseError:
+			if e.Err == ErrNoFileHeader || e.Err == ErrExtendedHeadersEOF {
+				return nil, io.EOF
+			}
+
+		case OverflowError:
+			r.nextFileFirstLine = []byte(e)
+			return fd, nil
+
+		default:
+			return nil, err
+		}
+	}
+
+	// Before reading hunks, check to see if there are any. If there
+	// aren't any, and there's another file after this file in the
+	// diff, then the hunks reader will complain ErrNoHunkHeader. It's
+	// not easy for us to tell from that error alone if that was
+	// caused by the lack of any hunks, or a malformatted hunk, so we
+	// need to perform the check here.
+	hr := fr.HunksReader()
+	line, err := readLine(r.reader)
+	if err != nil {
+		return fd, err
+	}
+	line = bytes.TrimSuffix(line, []byte{'\n'})
+	if bytes.HasPrefix(line, hunkPrefix) {
+		hr.nextHunkHeaderLine = line
+		fd.Hunks, err = hr.ReadAllHunks()
+		r.line = fr.line
+		r.offset = fr.offset
+		if err != nil {
+			if e0, ok := err.(*ParseError); ok {
+				if e, ok := e0.Err.(*ErrBadHunkLine); ok {
+					// This just means we finished reading the hunks for the
+					// current file. See the ErrBadHunkLine doc for more info.
+					r.nextFileFirstLine = e.Line
+					return fd, nil
+				}
+			}
+			return nil, err
+		}
+	} else {
+		// There weren't any hunks, so that line we peeked ahead at
+		// actually belongs to the next file. Put it back.
+		r.nextFileFirstLine = line
+	}
+
+	return fd, nil
+}
+
+// ReadAllFiles reads all file unified diffs (including headers and all
+// hunks) remaining in r.
+func (r *MultiFileDiffReader) ReadAllFiles() ([]*FileDiff, error) {
+	var ds []*FileDiff
+	for {
+		d, err := r.ReadFile()
+		if d != nil {
+			ds = append(ds, d)
+		}
+		if err == io.EOF {
+			return ds, nil
+		}
+		if err != nil {
+			return nil, err
+		}
+	}
+}
+
+// ParseFileDiff parses a file unified diff.
+func ParseFileDiff(diff []byte) (*FileDiff, error) {
+	return NewFileDiffReader(bytes.NewReader(diff)).Read()
+}
+
+// NewFileDiffReader returns a new FileDiffReader that reads a file
+// unified diff.
+func NewFileDiffReader(r io.Reader) *FileDiffReader {
+	return &FileDiffReader{reader: bufio.NewReader(r)}
+}
+
+// FileDiffReader reads a unified file diff.
+type FileDiffReader struct {
+	line   int
+	offset int64
+	reader *bufio.Reader
+
+	// fileHeaderLine is the first file header line, set by:
+	//
+	// (1) ReadExtendedHeaders if it encroaches on a file header line
+	//     (which it must to detect when extended headers are done); or
+	// (2) (*MultiFileDiffReader).ReadFile() if it encroaches on a
+	//     file header line while reading the previous file's hunks (in a
+	//     multi-file diff).
+	fileHeaderLine []byte
+}
+
+// Read reads a file unified diff, including headers and hunks, from r.
+func (r *FileDiffReader) Read() (*FileDiff, error) {
+	fd, err := r.ReadAllHeaders()
+	if err != nil {
+		return nil, err
+	}
+
+	fd.Hunks, err = r.HunksReader().ReadAllHunks()
+	if err != nil {
+		return nil, err
+	}
+
+	return fd, nil
+}
+
+// ReadAllHeaders reads the file headers and extended headers (if any)
+// from a file unified diff. It does not read hunks, and the returned
+// FileDiff's Hunks field is nil. To read the hunks, call the
+// (*FileDiffReader).HunksReader() method to get a HunksReader and
+// read hunks from that.
+func (r *FileDiffReader) ReadAllHeaders() (*FileDiff, error) {
+	var err error
+	fd := &FileDiff{}
+
+	fd.Extended, err = r.ReadExtendedHeaders()
+	if pe, ok := err.(*ParseError); ok && pe.Err == ErrExtendedHeadersEOF {
+		wasEmpty := handleEmpty(fd)
+		if wasEmpty {
+			return fd, nil
+		}
+		return fd, err
+	} else if _, ok := err.(OverflowError); ok {
+		handleEmpty(fd)
+		return fd, err
+	} else if err != nil {
+		return fd, err
+	}
+
+	var origTime, newTime *time.Time
+	fd.OrigName, fd.NewName, origTime, newTime, err = r.ReadFileHeaders()
+	if err != nil {
+		return nil, err
+	}
+	if origTime != nil {
+		ts := pbtypes.NewTimestamp(*origTime)
+		fd.OrigTime = &ts
+	}
+	if newTime != nil {
+		ts := pbtypes.NewTimestamp(*newTime)
+		fd.NewTime = &ts
+	}
+
+	return fd, nil
+}
+
+// HunksReader returns a new HunksReader that reads hunks from r. The
+// HunksReader's line and offset (used in error messages) is set to
+// start where the file diff header ended (which means errors have the
+// correct position information).
+func (r *FileDiffReader) HunksReader() *HunksReader {
+	return &HunksReader{
+		line:   r.line,
+		offset: r.offset,
+		reader: r.reader,
+	}
+}
+
+// ReadFileHeaders reads the unified file diff header (the lines that
+// start with "---" and "+++" with the orig/new file names and
+// timestamps).
+func (r *FileDiffReader) ReadFileHeaders() (origName, newName string, origTimestamp, newTimestamp *time.Time, err error) {
+	origName, origTimestamp, err = r.readOneFileHeader([]byte("--- "))
+	if err != nil {
+		return "", "", nil, nil, err
+	}
+
+	newName, newTimestamp, err = r.readOneFileHeader([]byte("+++ "))
+	if err != nil {
+		return "", "", nil, nil, err
+	}
+
+	return origName, newName, origTimestamp, newTimestamp, nil
+}
+
+// readOneFileHeader reads one of the file headers (prefix should be
+// either "+++ " or "--- ").
+func (r *FileDiffReader) readOneFileHeader(prefix []byte) (filename string, timestamp *time.Time, err error) {
+	var line []byte
+
+	if r.fileHeaderLine == nil {
+		var err error
+		line, err = readLine(r.reader)
+		if err == io.EOF {
+			return "", nil, &ParseError{r.line, r.offset, ErrNoFileHeader}
+		} else if err != nil {
+			return "", nil, err
+		}
+	} else {
+		line = r.fileHeaderLine
+		r.fileHeaderLine = nil
+	}
+
+	if !bytes.HasPrefix(line, prefix) {
+		return "", nil, &ParseError{r.line, r.offset, ErrBadFileHeader}
+	}
+
+	r.offset += int64(len(line))
+	r.line++
+	line = line[len(prefix):]
+
+	trimmedLine := strings.TrimSpace(string(line)) // filenames that contain spaces may be terminated by a tab
+	parts := strings.SplitN(trimmedLine, "\t", 2)
+	filename = parts[0]
+	if len(parts) == 2 {
+		// Timestamp is optional, but this header has it.
+		ts, err := time.Parse(diffTimeParseLayout, parts[1])
+		if err != nil {
+			return "", nil, err
+		}
+		timestamp = &ts
+	}
+
+	return filename, timestamp, err
+}
+
+// OverflowError is returned when we have overflowed into the start
+// of the next file while reading extended headers.
+type OverflowError string
+
+func (e OverflowError) Error() string {
+	return fmt.Sprintf("overflowed into next file: %s", e)
+}
+
+// ReadExtendedHeaders reads the extended header lines, if any, from a
+// unified diff file (e.g., git's "diff --git a/foo.go b/foo.go", "new
+// mode <mode>", "rename from <path>", etc.).
+func (r *FileDiffReader) ReadExtendedHeaders() ([]string, error) {
+	var xheaders []string
+	firstLine := true
+	for {
+		var line []byte
+		if r.fileHeaderLine == nil {
+			var err error
+			line, err = readLine(r.reader)
+			if err == io.EOF {
+				return xheaders, &ParseError{r.line, r.offset, ErrExtendedHeadersEOF}
+			} else if err != nil {
+				return xheaders, err
+			}
+		} else {
+			line = r.fileHeaderLine
+			r.fileHeaderLine = nil
+		}
+
+		if bytes.HasPrefix(line, []byte("diff --git ")) {
+			if firstLine {
+				firstLine = false
+			} else {
+				return xheaders, OverflowError(line)
+			}
+		}
+		if bytes.HasPrefix(line, []byte("--- ")) {
+			// We've reached the file header.
+			r.fileHeaderLine = line // pass to readOneFileHeader (see fileHeaderLine field doc)
+			return xheaders, nil
+		}
+
+		r.line++
+		r.offset += int64(len(line))
+		xheaders = append(xheaders, string(line))
+	}
+}
+
+// handleEmpty detects when FileDiff was an empty diff and will not have any hunks
+// that follow. It updates fd fields from the parsed extended headers.
+func handleEmpty(fd *FileDiff) (wasEmpty bool) {
+	switch {
+	case (len(fd.Extended) == 3 || len(fd.Extended) == 4 && strings.HasPrefix(fd.Extended[3], "Binary files ")) &&
+		strings.HasPrefix(fd.Extended[1], "new file mode ") && strings.HasPrefix(fd.Extended[0], "diff --git "):
+
+		names := strings.SplitN(fd.Extended[0][len("diff --git "):], " ", 2)
+		fd.OrigName = "/dev/null"
+		fd.NewName = names[1]
+		return true
+	case (len(fd.Extended) == 3 || len(fd.Extended) == 4 && strings.HasPrefix(fd.Extended[3], "Binary files ")) &&
+		strings.HasPrefix(fd.Extended[1], "deleted file mode ") && strings.HasPrefix(fd.Extended[0], "diff --git "):
+
+		names := strings.SplitN(fd.Extended[0][len("diff --git "):], " ", 2)
+		fd.OrigName = names[0]
+		fd.NewName = "/dev/null"
+		return true
+	case len(fd.Extended) == 4 && strings.HasPrefix(fd.Extended[2], "rename from ") && strings.HasPrefix(fd.Extended[3], "rename to ") && strings.HasPrefix(fd.Extended[0], "diff --git "):
+		names := strings.SplitN(fd.Extended[0][len("diff --git "):], " ", 2)
+		fd.OrigName = names[0]
+		fd.NewName = names[1]
+		return true
+	case len(fd.Extended) == 3 && strings.HasPrefix(fd.Extended[2], "Binary files ") && strings.HasPrefix(fd.Extended[0], "diff --git "):
+		names := strings.SplitN(fd.Extended[0][len("diff --git "):], " ", 2)
+		fd.OrigName = names[0]
+		fd.NewName = names[1]
+		return true
+	default:
+		return false
+	}
+}
+
+var (
+	// ErrNoFileHeader is when a file unified diff has no file header
+	// (i.e., the lines that begin with "---" and "+++").
+	ErrNoFileHeader = errors.New("expected file header, got EOF")
+
+	// ErrBadFileHeader is when a file unified diff has a malformed
+	// file header (i.e., the lines that begin with "---" and "+++").
+	ErrBadFileHeader = errors.New("bad file header")
+
+	// ErrExtendedHeadersEOF is when an EOF was encountered while reading extended file headers, which means that there were no ---/+++ headers encountered before hunks (if any) began.
+	ErrExtendedHeadersEOF = errors.New("expected file header while reading extended headers, got EOF")
+)
+
+// ParseHunks parses hunks from a unified diff. The diff must consist
+// only of hunks and not include a file header; if it has a file
+// header, use ParseFileDiff.
+func ParseHunks(diff []byte) ([]*Hunk, error) {
+	r := NewHunksReader(bytes.NewReader(diff))
+	hunks, err := r.ReadAllHunks()
+	if err != nil {
+		return nil, err
+	}
+	return hunks, nil
+}
+
+// NewHunksReader returns a new HunksReader that reads unified diff hunks
+// from r.
+func NewHunksReader(r io.Reader) *HunksReader {
+	return &HunksReader{reader: bufio.NewReader(r)}
+}
+
+// A HunksReader reads hunks from a unified diff.
+type HunksReader struct {
+	line   int
+	offset int64
+	hunk   *Hunk
+	reader *bufio.Reader
+
+	nextHunkHeaderLine []byte
+}
+
+// ReadHunk reads one hunk from r. If there are no more hunks, it
+// returns error io.EOF.
+func (r *HunksReader) ReadHunk() (*Hunk, error) {
+	r.hunk = nil
+	lastLineFromOrig := true
+	var line []byte
+	var err error
+	for {
+		if r.nextHunkHeaderLine != nil {
+			// Use stored hunk header line that was scanned in at the
+			// completion of the previous hunk's ReadHunk.
+			line = r.nextHunkHeaderLine
+			r.nextHunkHeaderLine = nil
+		} else {
+			line, err = readLine(r.reader)
+			if err != nil {
+				if err == io.EOF && r.hunk != nil {
+					return r.hunk, nil
+				}
+				return nil, err
+			}
+		}
+
+		// Record position.
+		r.line++
+		r.offset += int64(len(line))
+
+		if r.hunk == nil {
+			// Check for presence of hunk header.
+			if !bytes.HasPrefix(line, hunkPrefix) {
+				return nil, &ParseError{r.line, r.offset, ErrNoHunkHeader}
+			}
+
+			// Parse hunk header.
+			r.hunk = &Hunk{}
+			items := []interface{}{
+				&r.hunk.OrigStartLine, &r.hunk.OrigLines,
+				&r.hunk.NewStartLine, &r.hunk.NewLines,
+			}
+			header, section, err := normalizeHeader(string(line))
+			if err != nil {
+				return nil, &ParseError{r.line, r.offset, err}
+			}
+			n, err := fmt.Sscanf(header, hunkHeader, items...)
+			if err != nil {
+				return nil, err
+			}
+			if n < len(items) {
+				return nil, &ParseError{r.line, r.offset, &ErrBadHunkHeader{header: string(line)}}
+			}
+
+			r.hunk.Section = section
+		} else {
+			// Read hunk body line.
+			if bytes.HasPrefix(line, hunkPrefix) {
+				// Saw start of new hunk, so this hunk is
+				// complete. But we've already read in the next hunk's
+				// header, so we need to be sure that the next call to
+				// ReadHunk starts with that header.
+				r.nextHunkHeaderLine = line
+
+				// Rewind position.
+				r.line--
+				r.offset -= int64(len(line))
+
+				return r.hunk, nil
+			}
+
+			if len(line) >= 1 && !linePrefix(line[0]) {
+				// Bad hunk header line. If we're reading a multi-file
+				// diff, this may be the end of the current
+				// file. Return a "rich" error that lets our caller
+				// handle that case.
+				return r.hunk, &ParseError{r.line, r.offset, &ErrBadHunkLine{Line: line}}
+			}
+			if bytes.Equal(line, []byte(noNewlineMessage)) {
+				if lastLineFromOrig {
+					// Retain the newline in the body (otherwise the
+					// diff line would be like "-a+b", where "+b" is
+					// the the next line of the new file, which is not
+					// validly formatted) but record that the orig had
+					// no newline.
+					r.hunk.OrigNoNewlineAt = int32(len(r.hunk.Body))
+				} else {
+					// Remove previous line's newline.
+					if len(r.hunk.Body) != 0 {
+						r.hunk.Body = r.hunk.Body[:len(r.hunk.Body)-1]
+					}
+				}
+				continue
+			}
+
+			if len(line) > 0 {
+				lastLineFromOrig = line[0] == '-'
+			}
+
+			r.hunk.Body = append(r.hunk.Body, line...)
+			r.hunk.Body = append(r.hunk.Body, '\n')
+		}
+	}
+}
+
+const noNewlineMessage = `\ No newline at end of file`
+
+// linePrefixes is the set of all characters a valid line in a diff
+// hunk can start with. '\' can appear in diffs when no newline is
+// present at the end of a file.
+// See: 'http://www.gnu.org/software/diffutils/manual/diffutils.html#Incomplete-Lines'
+var linePrefixes = []byte{' ', '-', '+', '\\'}
+
+// linePrefix returns true if 'c' is in 'linePrefixes'.
+func linePrefix(c byte) bool {
+	for _, p := range linePrefixes {
+		if p == c {
+			return true
+		}
+	}
+	return false
+}
+
+// normalizeHeader takes a header of the form:
+// "@@ -linestart[,chunksize] +linestart[,chunksize] @@ section"
+// and returns two strings, with the first in the form:
+// "@@ -linestart,chunksize +linestart,chunksize @@".
+// where linestart and chunksize are both integers. The second is the
+// optional section header. chunksize may be omitted from the header
+// if its value is 1. normalizeHeader returns an error if the header
+// is not in the correct format.
+func normalizeHeader(header string) (string, string, error) {
+	// Split the header into five parts: the first '@@', the two
+	// ranges, the last '@@', and the optional section.
+	pieces := strings.SplitN(header, " ", 5)
+	if len(pieces) < 4 {
+		return "", "", &ErrBadHunkHeader{header: header}
+	}
+
+	if pieces[0] != "@@" {
+		return "", "", &ErrBadHunkHeader{header: header}
+	}
+	for i := 1; i < 3; i++ {
+		if !strings.ContainsRune(pieces[i], ',') {
+			pieces[i] = pieces[i] + ",1"
+		}
+	}
+	if pieces[3] != "@@" {
+		return "", "", &ErrBadHunkHeader{header: header}
+	}
+
+	var section string
+	if len(pieces) == 5 {
+		section = pieces[4]
+	}
+	return strings.Join(pieces, " "), strings.TrimSpace(section), nil
+}
+
+// ReadAllHunks reads all remaining hunks from r. A successful call
+// returns err == nil, not err == EOF. Because ReadAllHunks is defined
+// to read until EOF, it does not treat end of file as an error to be
+// reported.
+func (r *HunksReader) ReadAllHunks() ([]*Hunk, error) {
+	var hunks []*Hunk
+	linesRead := int32(0)
+	for {
+		hunk, err := r.ReadHunk()
+		if err == io.EOF {
+			return hunks, nil
+		}
+		if hunk != nil {
+			linesRead++ // account for the hunk header line
+			hunk.StartPosition = linesRead
+			hunks = append(hunks, hunk)
+			linesRead += int32(bytes.Count(hunk.Body, []byte{'\n'}))
+		}
+		if err != nil {
+			return hunks, err
+		}
+	}
+}
+
+// A ParseError is a description of a unified diff syntax error.
+type ParseError struct {
+	Line   int   // Line where the error occurred
+	Offset int64 // Offset where the error occurred
+	Err    error // The actual error
+}
+
+func (e *ParseError) Error() string {
+	return fmt.Sprintf("line %d, char %d: %s", e.Line, e.Offset, e.Err)
+}
+
+// ErrNoHunkHeader indicates that a unified diff hunk header was
+// expected but not found during parsing.
+var ErrNoHunkHeader = errors.New("no hunk header")
+
+// ErrBadHunkHeader indicates that a malformed unified diff hunk
+// header was encountered during parsing.
+type ErrBadHunkHeader struct {
+	header string
+}
+
+func (e *ErrBadHunkHeader) Error() string {
+	if e.header == "" {
+		return "bad hunk header"
+	}
+	return "bad hunk header: " + e.header
+}
+
+// ErrBadHunkLine is when a line not beginning with ' ', '-', '+', or
+// '\' is encountered while reading a hunk. In the context of reading
+// a single hunk or file, it is an unexpected error. In a multi-file
+// diff, however, it indicates that the current file's diff is
+// complete (and remaining diff data will describe another file
+// unified diff).
+type ErrBadHunkLine struct {
+	Line []byte
+}
+
+func (e *ErrBadHunkLine) Error() string {
+	m := "bad hunk line (does not start with ' ', '-', '+', or '\\')"
+	if len(e.Line) == 0 {
+		return m
+	}
+	return m + ": " + string(e.Line)
+}