forgejo/models/git_diff.go
mrsdizzie 7780ea8890 Fix ParsePatch function to work with quoted diff --git strings (#6323)
* Fix ParsePatch to work properly with quoted diff --git string

Currently ParsePatch fails when a diff contains a quoted diff line like:

diff --git "a/file" "b/file"

This patch makes it properly parse the line when that happens.

Fixes #6309

* Add test for regular case while here

* Simplify string modification
2019-03-14 18:09:53 +02:00

789 lines
21 KiB
Go

// Copyright 2014 The Gogs Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package models
import (
"bufio"
"bytes"
"fmt"
"html"
"html/template"
"io"
"io/ioutil"
"os"
"os/exec"
"regexp"
"sort"
"strconv"
"strings"
"code.gitea.io/git"
"code.gitea.io/gitea/modules/base"
"code.gitea.io/gitea/modules/highlight"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/process"
"code.gitea.io/gitea/modules/setting"
"github.com/Unknwon/com"
"github.com/sergi/go-diff/diffmatchpatch"
"golang.org/x/net/html/charset"
"golang.org/x/text/transform"
)
// DiffLineType represents the type of a DiffLine.
type DiffLineType uint8
// DiffLineType possible values.
const (
DiffLinePlain DiffLineType = iota + 1
DiffLineAdd
DiffLineDel
DiffLineSection
)
// DiffFileType represents the type of a DiffFile.
type DiffFileType uint8
// DiffFileType possible values.
const (
DiffFileAdd DiffFileType = iota + 1
DiffFileChange
DiffFileDel
DiffFileRename
)
// DiffLine represents a line difference in a DiffSection.
type DiffLine struct {
LeftIdx int
RightIdx int
Type DiffLineType
Content string
Comments []*Comment
}
// GetType returns the type of a DiffLine.
func (d *DiffLine) GetType() int {
return int(d.Type)
}
// CanComment returns whether or not a line can get commented
func (d *DiffLine) CanComment() bool {
return len(d.Comments) == 0 && d.Type != DiffLineSection
}
// GetCommentSide returns the comment side of the first comment, if not set returns empty string
func (d *DiffLine) GetCommentSide() string {
if len(d.Comments) == 0 {
return ""
}
return d.Comments[0].DiffSide()
}
// DiffSection represents a section of a DiffFile.
type DiffSection struct {
Name string
Lines []*DiffLine
}
var (
addedCodePrefix = []byte("<span class=\"added-code\">")
removedCodePrefix = []byte("<span class=\"removed-code\">")
codeTagSuffix = []byte("</span>")
)
func diffToHTML(diffs []diffmatchpatch.Diff, lineType DiffLineType) template.HTML {
buf := bytes.NewBuffer(nil)
// Reproduce signs which are cut for inline diff before.
switch lineType {
case DiffLineAdd:
buf.WriteByte('+')
case DiffLineDel:
buf.WriteByte('-')
}
for i := range diffs {
switch {
case diffs[i].Type == diffmatchpatch.DiffInsert && lineType == DiffLineAdd:
buf.Write(addedCodePrefix)
buf.WriteString(html.EscapeString(diffs[i].Text))
buf.Write(codeTagSuffix)
case diffs[i].Type == diffmatchpatch.DiffDelete && lineType == DiffLineDel:
buf.Write(removedCodePrefix)
buf.WriteString(html.EscapeString(diffs[i].Text))
buf.Write(codeTagSuffix)
case diffs[i].Type == diffmatchpatch.DiffEqual:
buf.WriteString(html.EscapeString(diffs[i].Text))
}
}
return template.HTML(buf.Bytes())
}
// GetLine gets a specific line by type (add or del) and file line number
func (diffSection *DiffSection) GetLine(lineType DiffLineType, idx int) *DiffLine {
var (
difference = 0
addCount = 0
delCount = 0
matchDiffLine *DiffLine
)
LOOP:
for _, diffLine := range diffSection.Lines {
switch diffLine.Type {
case DiffLineAdd:
addCount++
case DiffLineDel:
delCount++
default:
if matchDiffLine != nil {
break LOOP
}
difference = diffLine.RightIdx - diffLine.LeftIdx
addCount = 0
delCount = 0
}
switch lineType {
case DiffLineDel:
if diffLine.RightIdx == 0 && diffLine.LeftIdx == idx-difference {
matchDiffLine = diffLine
}
case DiffLineAdd:
if diffLine.LeftIdx == 0 && diffLine.RightIdx == idx+difference {
matchDiffLine = diffLine
}
}
}
if addCount == delCount {
return matchDiffLine
}
return nil
}
var diffMatchPatch = diffmatchpatch.New()
func init() {
diffMatchPatch.DiffEditCost = 100
}
// GetComputedInlineDiffFor computes inline diff for the given line.
func (diffSection *DiffSection) GetComputedInlineDiffFor(diffLine *DiffLine) template.HTML {
if setting.Git.DisableDiffHighlight {
return template.HTML(html.EscapeString(diffLine.Content[1:]))
}
var (
compareDiffLine *DiffLine
diff1 string
diff2 string
)
// try to find equivalent diff line. ignore, otherwise
switch diffLine.Type {
case DiffLineAdd:
compareDiffLine = diffSection.GetLine(DiffLineDel, diffLine.RightIdx)
if compareDiffLine == nil {
return template.HTML(html.EscapeString(diffLine.Content))
}
diff1 = compareDiffLine.Content
diff2 = diffLine.Content
case DiffLineDel:
compareDiffLine = diffSection.GetLine(DiffLineAdd, diffLine.LeftIdx)
if compareDiffLine == nil {
return template.HTML(html.EscapeString(diffLine.Content))
}
diff1 = diffLine.Content
diff2 = compareDiffLine.Content
default:
return template.HTML(html.EscapeString(diffLine.Content))
}
diffRecord := diffMatchPatch.DiffMain(diff1[1:], diff2[1:], true)
diffRecord = diffMatchPatch.DiffCleanupEfficiency(diffRecord)
return diffToHTML(diffRecord, diffLine.Type)
}
// DiffFile represents a file diff.
type DiffFile struct {
Name string
OldName string
Index int
Addition, Deletion int
Type DiffFileType
IsCreated bool
IsDeleted bool
IsBin bool
IsLFSFile bool
IsRenamed bool
IsSubmodule bool
Sections []*DiffSection
IsIncomplete bool
}
// GetType returns type of diff file.
func (diffFile *DiffFile) GetType() int {
return int(diffFile.Type)
}
// GetHighlightClass returns highlight class for a filename.
func (diffFile *DiffFile) GetHighlightClass() string {
return highlight.FileNameToHighlightClass(diffFile.Name)
}
// Diff represents a difference between two git trees.
type Diff struct {
TotalAddition, TotalDeletion int
Files []*DiffFile
IsIncomplete bool
}
// LoadComments loads comments into each line
func (diff *Diff) LoadComments(issue *Issue, currentUser *User) error {
allComments, err := FetchCodeComments(issue, currentUser)
if err != nil {
return err
}
for _, file := range diff.Files {
if lineCommits, ok := allComments[file.Name]; ok {
for _, section := range file.Sections {
for _, line := range section.Lines {
if comments, ok := lineCommits[int64(line.LeftIdx*-1)]; ok {
line.Comments = append(line.Comments, comments...)
}
if comments, ok := lineCommits[int64(line.RightIdx)]; ok {
line.Comments = append(line.Comments, comments...)
}
sort.SliceStable(line.Comments, func(i, j int) bool {
return line.Comments[i].CreatedUnix < line.Comments[j].CreatedUnix
})
}
}
}
}
return nil
}
// NumFiles returns number of files changes in a diff.
func (diff *Diff) NumFiles() int {
return len(diff.Files)
}
// Example: @@ -1,8 +1,9 @@ => [..., 1, 8, 1, 9]
var hunkRegex = regexp.MustCompile(`^@@ -(?P<beginOld>[0-9]+)(,(?P<endOld>[0-9]+))? \+(?P<beginNew>[0-9]+)(,(?P<endNew>[0-9]+))? @@`)
func isHeader(lof string) bool {
return strings.HasPrefix(lof, cmdDiffHead) || strings.HasPrefix(lof, "---") || strings.HasPrefix(lof, "+++")
}
// CutDiffAroundLine cuts a diff of a file in way that only the given line + numberOfLine above it will be shown
// it also recalculates hunks and adds the appropriate headers to the new diff.
// Warning: Only one-file diffs are allowed.
func CutDiffAroundLine(originalDiff io.Reader, line int64, old bool, numbersOfLine int) string {
if line == 0 || numbersOfLine == 0 {
// no line or num of lines => no diff
return ""
}
scanner := bufio.NewScanner(originalDiff)
hunk := make([]string, 0)
// begin is the start of the hunk containing searched line
// end is the end of the hunk ...
// currentLine is the line number on the side of the searched line (differentiated by old)
// otherLine is the line number on the opposite side of the searched line (differentiated by old)
var begin, end, currentLine, otherLine int64
var headerLines int
for scanner.Scan() {
lof := scanner.Text()
// Add header to enable parsing
if isHeader(lof) {
hunk = append(hunk, lof)
headerLines++
}
if currentLine > line {
break
}
// Detect "hunk" with contains commented lof
if strings.HasPrefix(lof, "@@") {
// Already got our hunk. End of hunk detected!
if len(hunk) > headerLines {
break
}
// A map with named groups of our regex to recognize them later more easily
submatches := hunkRegex.FindStringSubmatch(lof)
groups := make(map[string]string)
for i, name := range hunkRegex.SubexpNames() {
if i != 0 && name != "" {
groups[name] = submatches[i]
}
}
if old {
begin = com.StrTo(groups["beginOld"]).MustInt64()
end = com.StrTo(groups["endOld"]).MustInt64()
// init otherLine with begin of opposite side
otherLine = com.StrTo(groups["beginNew"]).MustInt64()
} else {
begin = com.StrTo(groups["beginNew"]).MustInt64()
if groups["endNew"] != "" {
end = com.StrTo(groups["endNew"]).MustInt64()
} else {
end = 0
}
// init otherLine with begin of opposite side
otherLine = com.StrTo(groups["beginOld"]).MustInt64()
}
end += begin // end is for real only the number of lines in hunk
// lof is between begin and end
if begin <= line && end >= line {
hunk = append(hunk, lof)
currentLine = begin
continue
}
} else if len(hunk) > headerLines {
hunk = append(hunk, lof)
// Count lines in context
switch lof[0] {
case '+':
if !old {
currentLine++
} else {
otherLine++
}
case '-':
if old {
currentLine++
} else {
otherLine++
}
default:
currentLine++
otherLine++
}
}
}
// No hunk found
if currentLine == 0 {
return ""
}
// headerLines + hunkLine (1) = totalNonCodeLines
if len(hunk)-headerLines-1 <= numbersOfLine {
// No need to cut the hunk => return existing hunk
return strings.Join(hunk, "\n")
}
var oldBegin, oldNumOfLines, newBegin, newNumOfLines int64
if old {
oldBegin = currentLine
newBegin = otherLine
} else {
oldBegin = otherLine
newBegin = currentLine
}
// headers + hunk header
newHunk := make([]string, headerLines)
// transfer existing headers
for idx, lof := range hunk[:headerLines] {
newHunk[idx] = lof
}
// transfer last n lines
for _, lof := range hunk[len(hunk)-numbersOfLine-1:] {
newHunk = append(newHunk, lof)
}
// calculate newBegin, ... by counting lines
for i := len(hunk) - 1; i >= len(hunk)-numbersOfLine; i-- {
switch hunk[i][0] {
case '+':
newBegin--
newNumOfLines++
case '-':
oldBegin--
oldNumOfLines++
default:
oldBegin--
newBegin--
newNumOfLines++
oldNumOfLines++
}
}
// construct the new hunk header
newHunk[headerLines] = fmt.Sprintf("@@ -%d,%d +%d,%d @@",
oldBegin, oldNumOfLines, newBegin, newNumOfLines)
return strings.Join(newHunk, "\n")
}
const cmdDiffHead = "diff --git "
// ParsePatch builds a Diff object from a io.Reader and some
// parameters.
// TODO: move this function to gogits/git-module
func ParsePatch(maxLines, maxLineCharacters, maxFiles int, reader io.Reader) (*Diff, error) {
var (
diff = &Diff{Files: make([]*DiffFile, 0)}
curFile = &DiffFile{}
curSection = &DiffSection{
Lines: make([]*DiffLine, 0, 10),
}
leftLine, rightLine int
lineCount int
curFileLinesCount int
curFileLFSPrefix bool
)
input := bufio.NewReader(reader)
isEOF := false
for !isEOF {
var linebuf bytes.Buffer
for {
b, err := input.ReadByte()
if err != nil {
if err == io.EOF {
isEOF = true
break
} else {
return nil, fmt.Errorf("ReadByte: %v", err)
}
}
if b == '\n' {
break
}
if linebuf.Len() < maxLineCharacters {
linebuf.WriteByte(b)
} else if linebuf.Len() == maxLineCharacters {
curFile.IsIncomplete = true
}
}
line := linebuf.String()
if strings.HasPrefix(line, "+++ ") || strings.HasPrefix(line, "--- ") || len(line) == 0 {
continue
}
trimLine := strings.Trim(line, "+- ")
if trimLine == LFSMetaFileIdentifier {
curFileLFSPrefix = true
}
if curFileLFSPrefix && strings.HasPrefix(trimLine, LFSMetaFileOidPrefix) {
oid := strings.TrimPrefix(trimLine, LFSMetaFileOidPrefix)
if len(oid) == 64 {
m := &LFSMetaObject{Oid: oid}
count, err := x.Count(m)
if err == nil && count > 0 {
curFile.IsBin = true
curFile.IsLFSFile = true
curSection.Lines = nil
}
}
}
curFileLinesCount++
lineCount++
// Diff data too large, we only show the first about maxLines lines
if curFileLinesCount >= maxLines {
curFile.IsIncomplete = true
}
switch {
case line[0] == ' ':
diffLine := &DiffLine{Type: DiffLinePlain, Content: line, LeftIdx: leftLine, RightIdx: rightLine}
leftLine++
rightLine++
curSection.Lines = append(curSection.Lines, diffLine)
continue
case line[0] == '@':
curSection = &DiffSection{}
curFile.Sections = append(curFile.Sections, curSection)
ss := strings.Split(line, "@@")
diffLine := &DiffLine{Type: DiffLineSection, Content: line}
curSection.Lines = append(curSection.Lines, diffLine)
// Parse line number.
ranges := strings.Split(ss[1][1:], " ")
leftLine, _ = com.StrTo(strings.Split(ranges[0], ",")[0][1:]).Int()
if len(ranges) > 1 {
rightLine, _ = com.StrTo(strings.Split(ranges[1], ",")[0]).Int()
} else {
log.Warn("Parse line number failed: %v", line)
rightLine = leftLine
}
continue
case line[0] == '+':
curFile.Addition++
diff.TotalAddition++
diffLine := &DiffLine{Type: DiffLineAdd, Content: line, RightIdx: rightLine}
rightLine++
curSection.Lines = append(curSection.Lines, diffLine)
continue
case line[0] == '-':
curFile.Deletion++
diff.TotalDeletion++
diffLine := &DiffLine{Type: DiffLineDel, Content: line, LeftIdx: leftLine}
if leftLine > 0 {
leftLine++
}
curSection.Lines = append(curSection.Lines, diffLine)
case strings.HasPrefix(line, "Binary"):
curFile.IsBin = true
continue
}
// Get new file.
if strings.HasPrefix(line, cmdDiffHead) {
middle := -1
// Note: In case file name is surrounded by double quotes (it happens only in git-shell).
// e.g. diff --git "a/xxx" "b/xxx"
hasQuote := line[len(cmdDiffHead)] == '"'
if hasQuote {
middle = strings.Index(line, ` "b/`)
} else {
middle = strings.Index(line, " b/")
}
beg := len(cmdDiffHead)
a := line[beg+2 : middle]
b := line[middle+3:]
if hasQuote {
// Keep the entire string in double quotes for now
a = line[beg:middle]
b = line[middle+1:]
var err error
a, err = strconv.Unquote(a)
if err != nil {
return nil, fmt.Errorf("Unquote: %v", err)
}
b, err = strconv.Unquote(b)
if err != nil {
return nil, fmt.Errorf("Unquote: %v", err)
}
// Now remove the /a /b
a = a[2:]
b = b[2:]
}
curFile = &DiffFile{
Name: b,
OldName: a,
Index: len(diff.Files) + 1,
Type: DiffFileChange,
Sections: make([]*DiffSection, 0, 10),
IsRenamed: a != b,
}
diff.Files = append(diff.Files, curFile)
if len(diff.Files) >= maxFiles {
diff.IsIncomplete = true
io.Copy(ioutil.Discard, reader)
break
}
curFileLinesCount = 0
curFileLFSPrefix = false
// Check file diff type and is submodule.
for {
line, err := input.ReadString('\n')
if err != nil {
if err == io.EOF {
isEOF = true
} else {
return nil, fmt.Errorf("ReadString: %v", err)
}
}
switch {
case strings.HasPrefix(line, "new file"):
curFile.Type = DiffFileAdd
curFile.IsCreated = true
case strings.HasPrefix(line, "deleted"):
curFile.Type = DiffFileDel
curFile.IsDeleted = true
case strings.HasPrefix(line, "index"):
curFile.Type = DiffFileChange
case strings.HasPrefix(line, "similarity index 100%"):
curFile.Type = DiffFileRename
}
if curFile.Type > 0 {
if strings.HasSuffix(line, " 160000\n") {
curFile.IsSubmodule = true
}
break
}
}
}
}
// FIXME: detect encoding while parsing.
var buf bytes.Buffer
for _, f := range diff.Files {
buf.Reset()
for _, sec := range f.Sections {
for _, l := range sec.Lines {
buf.WriteString(l.Content)
buf.WriteString("\n")
}
}
charsetLabel, err := base.DetectEncoding(buf.Bytes())
if charsetLabel != "UTF-8" && err == nil {
encoding, _ := charset.Lookup(charsetLabel)
if encoding != nil {
d := encoding.NewDecoder()
for _, sec := range f.Sections {
for _, l := range sec.Lines {
if c, _, err := transform.String(d, l.Content); err == nil {
l.Content = c
}
}
}
}
}
}
return diff, nil
}
// GetDiffRange builds a Diff between two commits of a repository.
// passing the empty string as beforeCommitID returns a diff from the
// parent commit.
func GetDiffRange(repoPath, beforeCommitID, afterCommitID string, maxLines, maxLineCharacters, maxFiles int) (*Diff, error) {
return GetDiffRangeWithWhitespaceBehavior(repoPath, beforeCommitID, afterCommitID, maxLines, maxLineCharacters, maxFiles, "")
}
// GetDiffRangeWithWhitespaceBehavior builds a Diff between two commits of a repository.
// Passing the empty string as beforeCommitID returns a diff from the parent commit.
// The whitespaceBehavior is either an empty string or a git flag
func GetDiffRangeWithWhitespaceBehavior(repoPath, beforeCommitID, afterCommitID string, maxLines, maxLineCharacters, maxFiles int, whitespaceBehavior string) (*Diff, error) {
gitRepo, err := git.OpenRepository(repoPath)
if err != nil {
return nil, err
}
commit, err := gitRepo.GetCommit(afterCommitID)
if err != nil {
return nil, err
}
var cmd *exec.Cmd
if len(beforeCommitID) == 0 && commit.ParentCount() == 0 {
cmd = exec.Command("git", "show", afterCommitID)
} else {
actualBeforeCommitID := beforeCommitID
if len(actualBeforeCommitID) == 0 {
parentCommit, _ := commit.Parent(0)
actualBeforeCommitID = parentCommit.ID.String()
}
diffArgs := []string{"diff", "-M"}
if len(whitespaceBehavior) != 0 {
diffArgs = append(diffArgs, whitespaceBehavior)
}
diffArgs = append(diffArgs, actualBeforeCommitID)
diffArgs = append(diffArgs, afterCommitID)
cmd = exec.Command("git", diffArgs...)
}
cmd.Dir = repoPath
cmd.Stderr = os.Stderr
stdout, err := cmd.StdoutPipe()
if err != nil {
return nil, fmt.Errorf("StdoutPipe: %v", err)
}
if err = cmd.Start(); err != nil {
return nil, fmt.Errorf("Start: %v", err)
}
pid := process.GetManager().Add(fmt.Sprintf("GetDiffRange [repo_path: %s]", repoPath), cmd)
defer process.GetManager().Remove(pid)
diff, err := ParsePatch(maxLines, maxLineCharacters, maxFiles, stdout)
if err != nil {
return nil, fmt.Errorf("ParsePatch: %v", err)
}
if err = cmd.Wait(); err != nil {
return nil, fmt.Errorf("Wait: %v", err)
}
return diff, nil
}
// RawDiffType type of a raw diff.
type RawDiffType string
// RawDiffType possible values.
const (
RawDiffNormal RawDiffType = "diff"
RawDiffPatch RawDiffType = "patch"
)
// GetRawDiff dumps diff results of repository in given commit ID to io.Writer.
// TODO: move this function to gogits/git-module
func GetRawDiff(repoPath, commitID string, diffType RawDiffType, writer io.Writer) error {
return GetRawDiffForFile(repoPath, "", commitID, diffType, "", writer)
}
// GetRawDiffForFile dumps diff results of file in given commit ID to io.Writer.
// TODO: move this function to gogits/git-module
func GetRawDiffForFile(repoPath, startCommit, endCommit string, diffType RawDiffType, file string, writer io.Writer) error {
repo, err := git.OpenRepository(repoPath)
if err != nil {
return fmt.Errorf("OpenRepository: %v", err)
}
commit, err := repo.GetCommit(endCommit)
if err != nil {
return fmt.Errorf("GetCommit: %v", err)
}
fileArgs := make([]string, 0)
if len(file) > 0 {
fileArgs = append(fileArgs, "--", file)
}
var cmd *exec.Cmd
switch diffType {
case RawDiffNormal:
if len(startCommit) != 0 {
cmd = exec.Command("git", append([]string{"diff", "-M", startCommit, endCommit}, fileArgs...)...)
} else if commit.ParentCount() == 0 {
cmd = exec.Command("git", append([]string{"show", endCommit}, fileArgs...)...)
} else {
c, _ := commit.Parent(0)
cmd = exec.Command("git", append([]string{"diff", "-M", c.ID.String(), endCommit}, fileArgs...)...)
}
case RawDiffPatch:
if len(startCommit) != 0 {
query := fmt.Sprintf("%s...%s", endCommit, startCommit)
cmd = exec.Command("git", append([]string{"format-patch", "--no-signature", "--stdout", "--root", query}, fileArgs...)...)
} else if commit.ParentCount() == 0 {
cmd = exec.Command("git", append([]string{"format-patch", "--no-signature", "--stdout", "--root", endCommit}, fileArgs...)...)
} else {
c, _ := commit.Parent(0)
query := fmt.Sprintf("%s...%s", endCommit, c.ID.String())
cmd = exec.Command("git", append([]string{"format-patch", "--no-signature", "--stdout", query}, fileArgs...)...)
}
default:
return fmt.Errorf("invalid diffType: %s", diffType)
}
stderr := new(bytes.Buffer)
cmd.Dir = repoPath
cmd.Stdout = writer
cmd.Stderr = stderr
if err = cmd.Run(); err != nil {
return fmt.Errorf("Run: %v - %s", err, stderr)
}
return nil
}
// GetDiffCommit builds a Diff representing the given commitID.
func GetDiffCommit(repoPath, commitID string, maxLines, maxLineCharacters, maxFiles int) (*Diff, error) {
return GetDiffRange(repoPath, "", commitID, maxLines, maxLineCharacters, maxFiles)
}