Files
gitea/modules/gitrepo/merge_tree.go

60 lines
2.0 KiB
Go

// Copyright 2026 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package gitrepo
import (
"bufio"
"context"
"fmt"
"gitea.dev/modules/git/gitcmd"
"gitea.dev/modules/util"
)
const MaxConflictedDetectFiles = 10
// MergeTree performs a merge between two commits (baseRef and headRef) with an optional merge base.
// It returns the resulting tree hash, a list of conflicted files (if any), and an error if the operation fails.
// If there are no conflicts, the list of conflicted files will be nil.
func MergeTree(ctx context.Context, repo Repository, baseRef, headRef, mergeBase string) (treeID string, isErrHasConflicts bool, conflictFiles []string, _ error) {
cmd := gitcmd.NewCommand("merge-tree", "--write-tree", "-z", "--name-only", "--no-messages").
AddOptionFormat("--merge-base=%s", mergeBase).
AddDynamicArguments(baseRef, headRef)
stdout, stdoutClose := cmd.MakeStdoutPipe()
defer stdoutClose()
cmd.WithPipelineFunc(func(ctx gitcmd.Context) error {
// https://git-scm.com/docs/git-merge-tree/2.38.0#OUTPUT
// For a conflicted merge, the output is:
// <OID of toplevel tree>NUL
// <Conflicted file name 1>NUL
// <Conflicted file name 2>NUL
// ...
scanner := bufio.NewScanner(stdout)
scanner.Split(util.BufioScannerSplit(0))
for scanner.Scan() {
line := scanner.Text()
if treeID == "" { // first line is tree ID
treeID = line
continue
}
conflictFiles = append(conflictFiles, line)
if len(conflictFiles) >= MaxConflictedDetectFiles {
break
}
}
return scanner.Err()
})
err := RunCmdWithStderr(ctx, repo, cmd)
// For a successful, non-conflicted merge, the exit status is 0. When the merge has conflicts, the exit status is 1.
// A merge can have conflicts without having individual files conflict
// https://git-scm.com/docs/git-merge-tree/2.38.0#_mistakes_to_avoid
isErrHasConflicts = gitcmd.IsErrorExitCode(err, 1)
if err == nil || isErrHasConflicts {
return treeID, isErrHasConflicts, conflictFiles, nil
}
return "", false, nil, fmt.Errorf("run merge-tree failed: %w", err)
}