2018-05-05 17:00:56 +03:00

141 lines
3.0 KiB
Go

package diff
import (
"bytes"
"fmt"
"io"
"time"
"sourcegraph.com/sqs/pbtypes"
)
// PrintMultiFileDiff prints a multi-file diff in unified diff format.
func PrintMultiFileDiff(ds []*FileDiff) ([]byte, error) {
var buf bytes.Buffer
for _, d := range ds {
diff, err := PrintFileDiff(d)
if err != nil {
return nil, err
}
if _, err := buf.Write(diff); err != nil {
return nil, err
}
}
return buf.Bytes(), nil
}
// PrintFileDiff prints a FileDiff in unified diff format.
//
// TODO(sqs): handle escaping whitespace/etc. chars in filenames
func PrintFileDiff(d *FileDiff) ([]byte, error) {
var buf bytes.Buffer
for _, xheader := range d.Extended {
if _, err := fmt.Fprintln(&buf, xheader); err != nil {
return nil, err
}
}
if d.Hunks == nil {
return buf.Bytes(), nil
}
if err := printFileHeader(&buf, "--- ", d.OrigName, timePtr(d.OrigTime)); err != nil {
return nil, err
}
if err := printFileHeader(&buf, "+++ ", d.NewName, timePtr(d.NewTime)); err != nil {
return nil, err
}
ph, err := PrintHunks(d.Hunks)
if err != nil {
return nil, err
}
if _, err := buf.Write(ph); err != nil {
return nil, err
}
return buf.Bytes(), nil
}
func timePtr(ts *pbtypes.Timestamp) *time.Time {
if ts == nil {
return nil
}
t := ts.Time()
return &t
}
func printFileHeader(w io.Writer, prefix string, filename string, timestamp *time.Time) error {
if _, err := fmt.Fprint(w, prefix, filename); err != nil {
return err
}
if timestamp != nil {
if _, err := fmt.Fprint(w, "\t", timestamp.Format(diffTimeFormatLayout)); err != nil {
return err
}
}
if _, err := fmt.Fprintln(w); err != nil {
return err
}
return nil
}
// PrintHunks prints diff hunks in unified diff format.
func PrintHunks(hunks []*Hunk) ([]byte, error) {
var buf bytes.Buffer
for _, hunk := range hunks {
_, err := fmt.Fprintf(&buf,
"@@ -%d,%d +%d,%d @@", hunk.OrigStartLine, hunk.OrigLines, hunk.NewStartLine, hunk.NewLines,
)
if err != nil {
return nil, err
}
if hunk.Section != "" {
_, err := fmt.Fprint(&buf, " ", hunk.Section)
if err != nil {
return nil, err
}
}
if _, err := fmt.Fprintln(&buf); err != nil {
return nil, err
}
if hunk.OrigNoNewlineAt == 0 {
if _, err := buf.Write(hunk.Body); err != nil {
return nil, err
}
} else {
if _, err := buf.Write(hunk.Body[:hunk.OrigNoNewlineAt]); err != nil {
return nil, err
}
if err := printNoNewlineMessage(&buf); err != nil {
return nil, err
}
if _, err := buf.Write(hunk.Body[hunk.OrigNoNewlineAt:]); err != nil {
return nil, err
}
}
if !bytes.HasSuffix(hunk.Body, []byte{'\n'}) {
if _, err := fmt.Fprintln(&buf); err != nil {
return nil, err
}
if err := printNoNewlineMessage(&buf); err != nil {
return nil, err
}
}
}
return buf.Bytes(), nil
}
func printNoNewlineMessage(w io.Writer) error {
if _, err := w.Write([]byte(noNewlineMessage)); err != nil {
return err
}
if _, err := fmt.Fprintln(w); err != nil {
return err
}
return nil
}