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gitea-fork-majority-judgment/modules/git/diff.go

275 lines
8.1 KiB

// Copyright 2020 The Gitea 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 git
import (
"bufio"
"bytes"
"context"
"fmt"
"io"
"os/exec"
"regexp"
"strconv"
"strings"
"code.gitea.io/gitea/modules/process"
)
// 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.
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.
func GetRawDiffForFile(repoPath, startCommit, endCommit string, diffType RawDiffType, file string, writer io.Writer) error {
repo, err := OpenRepository(repoPath)
if err != nil {
return fmt.Errorf("OpenRepository: %v", err)
}
defer repo.Close()
return GetRepoRawDiffForFile(repo, startCommit, endCommit, diffType, file, writer)
}
// GetRepoRawDiffForFile dumps diff results of file in given commit ID to io.Writer according given repository
func GetRepoRawDiffForFile(repo *Repository, startCommit, endCommit string, diffType RawDiffType, file string, writer io.Writer) error {
commit, err := repo.GetCommit(endCommit)
if err != nil {
return err
}
fileArgs := make([]string, 0)
if len(file) > 0 {
fileArgs = append(fileArgs, "--", file)
}
// FIXME: graceful: These commands should have a timeout
ctx, cancel := context.WithCancel(DefaultContext)
defer cancel()
var cmd *exec.Cmd
switch diffType {
case RawDiffNormal:
if len(startCommit) != 0 {
cmd = exec.CommandContext(ctx, GitExecutable, append([]string{"diff", "-M", startCommit, endCommit}, fileArgs...)...)
} else if commit.ParentCount() == 0 {
cmd = exec.CommandContext(ctx, GitExecutable, append([]string{"show", endCommit}, fileArgs...)...)
} else {
c, _ := commit.Parent(0)
cmd = exec.CommandContext(ctx, GitExecutable, append([]string{"diff", "-M", c.ID.String(), endCommit}, fileArgs...)...)
}
case RawDiffPatch:
if len(startCommit) != 0 {
query := fmt.Sprintf("%s...%s", endCommit, startCommit)
cmd = exec.CommandContext(ctx, GitExecutable, append([]string{"format-patch", "--no-signature", "--stdout", "--root", query}, fileArgs...)...)
} else if commit.ParentCount() == 0 {
cmd = exec.CommandContext(ctx, GitExecutable, 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.CommandContext(ctx, GitExecutable, append([]string{"format-patch", "--no-signature", "--stdout", query}, fileArgs...)...)
}
default:
return fmt.Errorf("invalid diffType: %s", diffType)
}
stderr := new(bytes.Buffer)
cmd.Dir = repo.Path
cmd.Stdout = writer
cmd.Stderr = stderr
pid := process.GetManager().Add(fmt.Sprintf("GetRawDiffForFile: [repo_path: %s]", repo.Path), cancel)
defer process.GetManager().Remove(pid)
if err = cmd.Run(); err != nil {
return fmt.Errorf("Run: %v - %s", err, stderr)
}
return nil
}
// ParseDiffHunkString parse the diffhunk content and return
func ParseDiffHunkString(diffhunk string) (leftLine, leftHunk, rightLine, righHunk int) {
ss := strings.Split(diffhunk, "@@")
ranges := strings.Split(ss[1][1:], " ")
leftRange := strings.Split(ranges[0], ",")
leftLine, _ = strconv.Atoi(leftRange[0][1:])
if len(leftRange) > 1 {
leftHunk, _ = strconv.Atoi(leftRange[1])
}
if len(ranges) > 1 {
rightRange := strings.Split(ranges[1], ",")
rightLine, _ = strconv.Atoi(rightRange[0])
if len(rightRange) > 1 {
righHunk, _ = strconv.Atoi(rightRange[1])
}
} else {
log("Parse line number failed: %v", diffhunk)
rightLine = leftLine
righHunk = leftHunk
}
return
}
// 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]+))? @@`)
const cmdDiffHead = "diff --git "
func isHeader(lof string, inHunk bool) bool {
return strings.HasPrefix(lof, cmdDiffHead) || (!inHunk && (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, error) {
if line == 0 || numbersOfLine == 0 {
// no line or num of lines => no diff
return "", nil
}
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
inHunk := false
for scanner.Scan() {
lof := scanner.Text()
// Add header to enable parsing
if isHeader(lof, inHunk) {
if strings.HasPrefix(lof, cmdDiffHead) {
inHunk = false
}
hunk = append(hunk, lof)
headerLines++
}
if currentLine > line {
break
}
// Detect "hunk" with contains commented lof
if strings.HasPrefix(lof, "@@") {
inHunk = true
// 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, _ = strconv.ParseInt(groups["beginOld"], 10, 64)
end, _ = strconv.ParseInt(groups["endOld"], 10, 64)
// init otherLine with begin of opposite side
otherLine, _ = strconv.ParseInt(groups["beginNew"], 10, 64)
} else {
begin, _ = strconv.ParseInt(groups["beginNew"], 10, 64)
if groups["endNew"] != "" {
end, _ = strconv.ParseInt(groups["endNew"], 10, 64)
} else {
end = 0
}
// init otherLine with begin of opposite side
otherLine, _ = strconv.ParseInt(groups["beginOld"], 10, 64)
}
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++
}
}
}
err := scanner.Err()
if err != nil {
return "", err
}
// No hunk found
if currentLine == 0 {
return "", nil
}
// headerLines + hunkLine (1) = totalNonCodeLines
if len(hunk)-headerLines-1 <= numbersOfLine {
// No need to cut the hunk => return existing hunk
return strings.Join(hunk, "\n"), nil
}
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
copy(newHunk, hunk[:headerLines])
// transfer last n lines
newHunk = append(newHunk, hunk[len(hunk)-numbersOfLine-1:]...)
// 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"), nil
}