modules/git/pipeline/revlist.go

@@ -42,10 +42,7 @@ func RevListObjects(ctx context.Context, revListWriter *io.PipeWriter, wg *sync.
 	defer revListWriter.Close()
 	stderr := new(bytes.Buffer)
 	var errbuf strings.Builder
-	cmd := git.NewCommand(ctx, "rev-list", "--objects").AddDynamicArguments(headSHA)
-	if baseSHA != "" {
-		cmd = cmd.AddArguments("--not").AddDynamicArguments(baseSHA)
-	}
+	cmd := git.NewCommand(ctx, "rev-list", "--objects").AddDynamicArguments(headSHA).AddArguments("--not").AddDynamicArguments(baseSHA)
 	if err := cmd.Run(&git.RunOpts{
 		Dir:    tmpBasePath,
 		Stdout: revListWriter,

routers/web/org/projects.go

@@ -103,7 +103,7 @@ func Projects(ctx *context.Context) {
 	pager.AddParam(ctx, "state", "State")
 	ctx.Data["Page"] = pager
 
-	ctx.Data["CanWriteProjects"] = canWriteProjects(ctx)
+	ctx.Data["CanWriteProjects"] = canWriteUnit(ctx)
 	ctx.Data["IsShowClosed"] = isShowClosed
 	ctx.Data["PageIsViewProjects"] = true
 	ctx.Data["SortType"] = sortType
@@ -111,7 +111,7 @@ func Projects(ctx *context.Context) {
 	ctx.HTML(http.StatusOK, tplProjects)
 }
 
-func canWriteProjects(ctx *context.Context) bool {
+func canWriteUnit(ctx *context.Context) bool {
 	if ctx.ContextUser.IsOrganization() {
 		return ctx.Org.CanWriteUnit(ctx, unit.TypeProjects)
 	}
@@ -122,7 +122,7 @@ func canWriteProjects(ctx *context.Context) bool {
 func NewProject(ctx *context.Context) {
 	ctx.Data["Title"] = ctx.Tr("repo.projects.new")
 	ctx.Data["BoardTypes"] = project_model.GetBoardConfig()
-	ctx.Data["CanWriteProjects"] = canWriteProjects(ctx)
+	ctx.Data["CanWriteProjects"] = canWriteUnit(ctx)
 	ctx.Data["HomeLink"] = ctx.ContextUser.HomeLink()
 	shared_user.RenderUserHeader(ctx)
 	ctx.HTML(http.StatusOK, tplProjectsNew)
@@ -135,7 +135,7 @@ func NewProjectPost(ctx *context.Context) {
 	shared_user.RenderUserHeader(ctx)
 
 	if ctx.HasError() {
-		ctx.Data["CanWriteProjects"] = canWriteProjects(ctx)
+		ctx.Data["CanWriteProjects"] = canWriteUnit(ctx)
 		ctx.Data["PageIsViewProjects"] = true
 		ctx.Data["BoardTypes"] = project_model.GetBoardConfig()
 		ctx.HTML(http.StatusOK, tplProjectsNew)
@@ -193,7 +193,7 @@ func DeleteProject(ctx *context.Context) {
 		}
 		return
 	}
-	if p.OwnerID != ctx.ContextUser.ID {
+	if p.RepoID != ctx.Repo.Repository.ID {
 		ctx.NotFound("", nil)
 		return
 	}
@@ -214,7 +214,7 @@ func EditProject(ctx *context.Context) {
 	ctx.Data["Title"] = ctx.Tr("repo.projects.edit")
 	ctx.Data["PageIsEditProjects"] = true
 	ctx.Data["PageIsViewProjects"] = true
-	ctx.Data["CanWriteProjects"] = canWriteProjects(ctx)
+	ctx.Data["CanWriteProjects"] = canWriteUnit(ctx)
 	shared_user.RenderUserHeader(ctx)
 
 	p, err := project_model.GetProjectByID(ctx, ctx.ParamsInt64(":id"))
@@ -226,7 +226,7 @@ func EditProject(ctx *context.Context) {
 		}
 		return
 	}
-	if p.OwnerID != ctx.ContextUser.ID {
+	if p.RepoID != ctx.Repo.Repository.ID {
 		ctx.NotFound("", nil)
 		return
 	}
@@ -243,7 +243,7 @@ func EditProjectPost(ctx *context.Context) {
 	ctx.Data["Title"] = ctx.Tr("repo.projects.edit")
 	ctx.Data["PageIsEditProjects"] = true
 	ctx.Data["PageIsViewProjects"] = true
-	ctx.Data["CanWriteProjects"] = canWriteProjects(ctx)
+	ctx.Data["CanWriteProjects"] = canWriteUnit(ctx)
 	shared_user.RenderUserHeader(ctx)
 
 	if ctx.HasError() {
@@ -260,7 +260,7 @@ func EditProjectPost(ctx *context.Context) {
 		}
 		return
 	}
-	if p.OwnerID != ctx.ContextUser.ID {
+	if p.RepoID != ctx.Repo.Repository.ID {
 		ctx.NotFound("", nil)
 		return
 	}
@@ -332,7 +332,7 @@ func ViewProject(ctx *context.Context) {
 	project.RenderedContent = project.Description
 	ctx.Data["LinkedPRs"] = linkedPrsMap
 	ctx.Data["PageIsViewProjects"] = true
-	ctx.Data["CanWriteProjects"] = canWriteProjects(ctx)
+	ctx.Data["CanWriteProjects"] = canWriteUnit(ctx)
 	ctx.Data["Project"] = project
 	ctx.Data["IssuesMap"] = issuesMap
 	ctx.Data["Boards"] = boards

services/pull/lfs.go

@@ -116,7 +116,7 @@ func createLFSMetaObjectsFromCatFileBatch(catFileBatchReader *io.PipeReader, wg
 		}
 
 		// Then we need to check that this pointer is in the db
-		if _, err := git_model.GetLFSMetaObjectByOid(db.DefaultContext, pr.HeadRepoID, pointer.Oid); err != nil {
+		if _, err := git_model.GetLFSMetaObjectByOid(db.DefaultContext, pr.HeadRepo.ID, pointer.Oid); err != nil {
 			if err == git_model.ErrLFSObjectNotExist {
 				log.Warn("During merge of: %d in %-v, there is a pointer to LFS Oid: %s which although present in the LFS store is not associated with the head repo %-v", pr.Index, pr.BaseRepo, pointer.Oid, pr.HeadRepo)
 				continue

services/pull/merge.go

@@ -5,6 +5,8 @@
 package pull
 
 import (
+	"bufio"
+	"bytes"
 	"context"
 	"fmt"
 	"os"
@@ -12,6 +14,7 @@ import (
 	"regexp"
 	"strconv"
 	"strings"
+	"time"
 
 	"code.gitea.io/gitea/models"
 	"code.gitea.io/gitea/models/db"
@@ -31,17 +34,22 @@ import (
 	repo_module "code.gitea.io/gitea/modules/repository"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/timeutil"
+	asymkey_service "code.gitea.io/gitea/services/asymkey"
 	issue_service "code.gitea.io/gitea/services/issue"
 )
 
 // GetDefaultMergeMessage returns default message used when merging pull request
 func GetDefaultMergeMessage(ctx context.Context, baseGitRepo *git.Repository, pr *issues_model.PullRequest, mergeStyle repo_model.MergeStyle) (message, body string, err error) {
-	if err := pr.LoadBaseRepo(ctx); err != nil {
-		return "", "", err
-	}
 	if err := pr.LoadHeadRepo(ctx); err != nil {
 		return "", "", err
 	}
+	if err := pr.LoadBaseRepo(ctx); err != nil {
+		return "", "", err
+	}
+	if pr.BaseRepo == nil {
+		return "", "", repo_model.ErrRepoNotExist{ID: pr.BaseRepoID}
+	}
+
 	if err := pr.LoadIssue(ctx); err != nil {
 		return "", "", err
 	}
@@ -136,19 +144,18 @@ func expandDefaultMergeMessage(template string, vars map[string]string) (message
 // Merge merges pull request to base repository.
 // Caller should check PR is ready to be merged (review and status checks)
 func Merge(ctx context.Context, pr *issues_model.PullRequest, doer *user_model.User, baseGitRepo *git.Repository, mergeStyle repo_model.MergeStyle, expectedHeadCommitID, message string, wasAutoMerged bool) error {
-	if err := pr.LoadBaseRepo(ctx); err != nil {
-		log.Error("Unable to load base repo: %v", err)
-		return fmt.Errorf("unable to load base repo: %w", err)
-	} else if err := pr.LoadHeadRepo(ctx); err != nil {
-		log.Error("Unable to load head repo: %v", err)
-		return fmt.Errorf("unable to load head repo: %w", err)
+	if err := pr.LoadHeadRepo(ctx); err != nil {
+		log.Error("LoadHeadRepo: %v", err)
+		return fmt.Errorf("LoadHeadRepo: %w", err)
+	} else if err := pr.LoadBaseRepo(ctx); err != nil {
+		log.Error("LoadBaseRepo: %v", err)
+		return fmt.Errorf("LoadBaseRepo: %w", err)
 	}
 
 	pullWorkingPool.CheckIn(fmt.Sprint(pr.ID))
 	defer pullWorkingPool.CheckOut(fmt.Sprint(pr.ID))
 
 	// Removing an auto merge pull and ignore if not exist
-	// FIXME: is this the correct point to do this? Shouldn't this be after IsMergeStyleAllowed?
 	if err := pull_model.DeleteScheduledAutoMerge(ctx, pr.ID); err != nil && !db.IsErrNotExist(err) {
 		return err
 	}
@@ -172,7 +179,7 @@ func Merge(ctx context.Context, pr *issues_model.PullRequest, doer *user_model.U
 	// Run the merge in the hammer context to prevent cancellation
 	hammerCtx := graceful.GetManager().HammerContext()
 
-	pr.MergedCommitID, err = doMergeAndPush(hammerCtx, pr, doer, mergeStyle, expectedHeadCommitID, message)
+	pr.MergedCommitID, err = rawMerge(hammerCtx, pr, doer, mergeStyle, expectedHeadCommitID, message)
 	if err != nil {
 		return err
 	}
@@ -182,18 +189,18 @@ func Merge(ctx context.Context, pr *issues_model.PullRequest, doer *user_model.U
 	pr.MergerID = doer.ID
 
 	if _, err := pr.SetMerged(hammerCtx); err != nil {
-		log.Error("SetMerged %-v: %v", pr, err)
+		log.Error("SetMerged [%d]: %v", pr.ID, err)
 	}
 
 	if err := pr.LoadIssue(hammerCtx); err != nil {
-		log.Error("LoadIssue %-v: %v", pr, err)
+		log.Error("LoadIssue [%d]: %v", pr.ID, err)
 	}
 
 	if err := pr.Issue.LoadRepo(hammerCtx); err != nil {
-		log.Error("pr.Issue.LoadRepo %-v: %v", pr, err)
+		log.Error("LoadRepo for issue [%d]: %v", pr.ID, err)
 	}
 	if err := pr.Issue.Repo.LoadOwner(hammerCtx); err != nil {
-		log.Error("LoadOwner for %-v: %v", pr, err)
+		log.Error("LoadOwner for PR [%d]: %v", pr.ID, err)
 	}
 
 	if wasAutoMerged {
@@ -232,43 +239,326 @@ func Merge(ctx context.Context, pr *issues_model.PullRequest, doer *user_model.U
 	return nil
 }
 
-// doMergeAndPush performs the merge operation without changing any pull information in database and pushes it up to the base repository
-func doMergeAndPush(ctx context.Context, pr *issues_model.PullRequest, doer *user_model.User, mergeStyle repo_model.MergeStyle, expectedHeadCommitID, message string) (string, error) {
+// rawMerge perform the merge operation without changing any pull information in database
+func rawMerge(ctx context.Context, pr *issues_model.PullRequest, doer *user_model.User, mergeStyle repo_model.MergeStyle, expectedHeadCommitID, message string) (string, error) {
 	// Clone base repo.
-	mergeCtx, cancel, err := createTemporaryRepoForMerge(ctx, pr, doer, expectedHeadCommitID)
+	tmpBasePath, err := createTemporaryRepo(ctx, pr)
 	if err != nil {
+		log.Error("CreateTemporaryPath: %v", err)
 		return "", err
 	}
-	defer cancel()
+	defer func() {
+		if err := repo_module.RemoveTemporaryPath(tmpBasePath); err != nil {
+			log.Error("Merge: RemoveTemporaryPath: %s", err)
+		}
+	}()
+
+	baseBranch := "base"
+	trackingBranch := "tracking"
+	stagingBranch := "staging"
+
+	if expectedHeadCommitID != "" {
+		trackingCommitID, _, err := git.NewCommand(ctx, "show-ref", "--hash").AddDynamicArguments(git.BranchPrefix + trackingBranch).RunStdString(&git.RunOpts{Dir: tmpBasePath})
+		if err != nil {
+			log.Error("show-ref[%s] --hash refs/heads/trackingn: %v", tmpBasePath, git.BranchPrefix+trackingBranch, err)
+			return "", fmt.Errorf("getDiffTree: %w", err)
+		}
+		if strings.TrimSpace(trackingCommitID) != expectedHeadCommitID {
+			return "", models.ErrSHADoesNotMatch{
+				GivenSHA:   expectedHeadCommitID,
+				CurrentSHA: trackingCommitID,
+			}
+		}
+	}
+
+	var outbuf, errbuf strings.Builder
+
+	// Enable sparse-checkout
+	sparseCheckoutList, err := getDiffTree(ctx, tmpBasePath, baseBranch, trackingBranch)
+	if err != nil {
+		log.Error("getDiffTree(%s, %s, %s): %v", tmpBasePath, baseBranch, trackingBranch, err)
+		return "", fmt.Errorf("getDiffTree: %w", err)
+	}
+
+	infoPath := filepath.Join(tmpBasePath, ".git", "info")
+	if err := os.MkdirAll(infoPath, 0o700); err != nil {
+		log.Error("Unable to create .git/info in %s: %v", tmpBasePath, err)
+		return "", fmt.Errorf("Unable to create .git/info in tmpBasePath: %w", err)
+	}
+
+	sparseCheckoutListPath := filepath.Join(infoPath, "sparse-checkout")
+	if err := os.WriteFile(sparseCheckoutListPath, []byte(sparseCheckoutList), 0o600); err != nil {
+		log.Error("Unable to write .git/info/sparse-checkout file in %s: %v", tmpBasePath, err)
+		return "", fmt.Errorf("Unable to write .git/info/sparse-checkout file in tmpBasePath: %w", err)
+	}
+
+	gitConfigCommand := func() *git.Command {
+		return git.NewCommand(ctx, "config", "--local")
+	}
+
+	// Switch off LFS process (set required, clean and smudge here also)
+	if err := gitConfigCommand().AddArguments("filter.lfs.process", "").
+		Run(&git.RunOpts{
+			Dir:    tmpBasePath,
+			Stdout: &outbuf,
+			Stderr: &errbuf,
+		}); err != nil {
+		log.Error("git config [filter.lfs.process -> <> ]: %v\n%s\n%s", err, outbuf.String(), errbuf.String())
+		return "", fmt.Errorf("git config [filter.lfs.process -> <> ]: %w\n%s\n%s", err, outbuf.String(), errbuf.String())
+	}
+	outbuf.Reset()
+	errbuf.Reset()
+
+	if err := gitConfigCommand().AddArguments("filter.lfs.required", "false").
+		Run(&git.RunOpts{
+			Dir:    tmpBasePath,
+			Stdout: &outbuf,
+			Stderr: &errbuf,
+		}); err != nil {
+		log.Error("git config [filter.lfs.required -> <false> ]: %v\n%s\n%s", err, outbuf.String(), errbuf.String())
+		return "", fmt.Errorf("git config [filter.lfs.required -> <false> ]: %w\n%s\n%s", err, outbuf.String(), errbuf.String())
+	}
+	outbuf.Reset()
+	errbuf.Reset()
+
+	if err := gitConfigCommand().AddArguments("filter.lfs.clean", "").
+		Run(&git.RunOpts{
+			Dir:    tmpBasePath,
+			Stdout: &outbuf,
+			Stderr: &errbuf,
+		}); err != nil {
+		log.Error("git config [filter.lfs.clean -> <> ]: %v\n%s\n%s", err, outbuf.String(), errbuf.String())
+		return "", fmt.Errorf("git config [filter.lfs.clean -> <> ]: %w\n%s\n%s", err, outbuf.String(), errbuf.String())
+	}
+	outbuf.Reset()
+	errbuf.Reset()
+
+	if err := gitConfigCommand().AddArguments("filter.lfs.smudge", "").
+		Run(&git.RunOpts{
+			Dir:    tmpBasePath,
+			Stdout: &outbuf,
+			Stderr: &errbuf,
+		}); err != nil {
+		log.Error("git config [filter.lfs.smudge -> <> ]: %v\n%s\n%s", err, outbuf.String(), errbuf.String())
+		return "", fmt.Errorf("git config [filter.lfs.smudge -> <> ]: %w\n%s\n%s", err, outbuf.String(), errbuf.String())
+	}
+	outbuf.Reset()
+	errbuf.Reset()
+
+	if err := gitConfigCommand().AddArguments("core.sparseCheckout", "true").
+		Run(&git.RunOpts{
+			Dir:    tmpBasePath,
+			Stdout: &outbuf,
+			Stderr: &errbuf,
+		}); err != nil {
+		log.Error("git config [core.sparseCheckout -> true ]: %v\n%s\n%s", err, outbuf.String(), errbuf.String())
+		return "", fmt.Errorf("git config [core.sparsecheckout -> true]: %w\n%s\n%s", err, outbuf.String(), errbuf.String())
+	}
+	outbuf.Reset()
+	errbuf.Reset()
+
+	// Read base branch index
+	if err := git.NewCommand(ctx, "read-tree", "HEAD").
+		Run(&git.RunOpts{
+			Dir:    tmpBasePath,
+			Stdout: &outbuf,
+			Stderr: &errbuf,
+		}); err != nil {
+		log.Error("git read-tree HEAD: %v\n%s\n%s", err, outbuf.String(), errbuf.String())
+		return "", fmt.Errorf("Unable to read base branch in to the index: %w\n%s\n%s", err, outbuf.String(), errbuf.String())
+	}
+	outbuf.Reset()
+	errbuf.Reset()
+
+	sig := doer.NewGitSig()
+	committer := sig
+
+	// Determine if we should sign. If no signKeyID, use --no-gpg-sign to countermand the sign config (from gitconfig)
+	var signArgs git.TrustedCmdArgs
+	sign, signKeyID, signer, _ := asymkey_service.SignMerge(ctx, pr, doer, tmpBasePath, "HEAD", trackingBranch)
+	if sign {
+		if pr.BaseRepo.GetTrustModel() == repo_model.CommitterTrustModel || pr.BaseRepo.GetTrustModel() == repo_model.CollaboratorCommitterTrustModel {
+			committer = signer
+		}
+		signArgs = git.ToTrustedCmdArgs([]string{"-S" + signKeyID})
+	} else {
+		signArgs = append(signArgs, "--no-gpg-sign")
+	}
+
+	commitTimeStr := time.Now().Format(time.RFC3339)
+
+	// Because this may call hooks we should pass in the environment
+	env := append(os.Environ(),
+		"GIT_AUTHOR_NAME="+sig.Name,
+		"GIT_AUTHOR_EMAIL="+sig.Email,
+		"GIT_AUTHOR_DATE="+commitTimeStr,
+		"GIT_COMMITTER_NAME="+committer.Name,
+		"GIT_COMMITTER_EMAIL="+committer.Email,
+		"GIT_COMMITTER_DATE="+commitTimeStr,
+	)
 
 	// Merge commits.
 	switch mergeStyle {
 	case repo_model.MergeStyleMerge:
-		if err := doMergeStyleMerge(mergeCtx, message); err != nil {
+		cmd := git.NewCommand(ctx, "merge", "--no-ff", "--no-commit").AddDynamicArguments(trackingBranch)
+		if err := runMergeCommand(pr, mergeStyle, cmd, tmpBasePath); err != nil {
+			log.Error("Unable to merge tracking into base: %v", err)
 			return "", err
 		}
-	case repo_model.MergeStyleRebase, repo_model.MergeStyleRebaseMerge:
-		if err := doMergeStyleRebase(mergeCtx, mergeStyle, message); err != nil {
+
+		if err := commitAndSignNoAuthor(ctx, pr, message, signArgs, tmpBasePath, env); err != nil {
+			log.Error("Unable to make final commit: %v", err)
 			return "", err
 		}
+	case repo_model.MergeStyleRebase:
+		fallthrough
+	case repo_model.MergeStyleRebaseUpdate:
+		fallthrough
+	case repo_model.MergeStyleRebaseMerge:
+		// Checkout head branch
+		if err := git.NewCommand(ctx, "checkout", "-b").AddDynamicArguments(stagingBranch, trackingBranch).
+			Run(&git.RunOpts{
+				Dir:    tmpBasePath,
+				Stdout: &outbuf,
+				Stderr: &errbuf,
+			}); err != nil {
+			log.Error("git checkout base prior to merge post staging rebase [%s:%s -> %s:%s]: %v\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+			return "", fmt.Errorf("git checkout base prior to merge post staging rebase  [%s:%s -> %s:%s]: %w\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+		}
+		outbuf.Reset()
+		errbuf.Reset()
+
+		// Rebase before merging
+		if err := git.NewCommand(ctx, "rebase").AddDynamicArguments(baseBranch).
+			Run(&git.RunOpts{
+				Dir:    tmpBasePath,
+				Stdout: &outbuf,
+				Stderr: &errbuf,
+			}); err != nil {
+			// Rebase will leave a REBASE_HEAD file in .git if there is a conflict
+			if _, statErr := os.Stat(filepath.Join(tmpBasePath, ".git", "REBASE_HEAD")); statErr == nil {
+				var commitSha string
+				ok := false
+				failingCommitPaths := []string{
+					filepath.Join(tmpBasePath, ".git", "rebase-apply", "original-commit"), // Git < 2.26
+					filepath.Join(tmpBasePath, ".git", "rebase-merge", "stopped-sha"),     // Git >= 2.26
+				}
+				for _, failingCommitPath := range failingCommitPaths {
+					if _, statErr := os.Stat(failingCommitPath); statErr == nil {
+						commitShaBytes, readErr := os.ReadFile(failingCommitPath)
+						if readErr != nil {
+							// Abandon this attempt to handle the error
+							log.Error("git rebase staging on to base [%s:%s -> %s:%s]: %v\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+							return "", fmt.Errorf("git rebase staging on to base [%s:%s -> %s:%s]: %w\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+						}
+						commitSha = strings.TrimSpace(string(commitShaBytes))
+						ok = true
+						break
+					}
+				}
+				if !ok {
+					log.Error("Unable to determine failing commit sha for this rebase message. Cannot cast as models.ErrRebaseConflicts.")
+					log.Error("git rebase staging on to base [%s:%s -> %s:%s]: %v\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+					return "", fmt.Errorf("git rebase staging on to base [%s:%s -> %s:%s]: %w\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+				}
+				log.Debug("RebaseConflict at %s [%s:%s -> %s:%s]: %v\n%s\n%s", commitSha, pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+				return "", models.ErrRebaseConflicts{
+					Style:     mergeStyle,
+					CommitSHA: commitSha,
+					StdOut:    outbuf.String(),
+					StdErr:    errbuf.String(),
+					Err:       err,
+				}
+			}
+			log.Error("git rebase staging on to base [%s:%s -> %s:%s]: %v\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+			return "", fmt.Errorf("git rebase staging on to base [%s:%s -> %s:%s]: %w\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+		}
+		outbuf.Reset()
+		errbuf.Reset()
+
+		// not need merge, just update by rebase. so skip
+		if mergeStyle == repo_model.MergeStyleRebaseUpdate {
+			break
+		}
+
+		// Checkout base branch again
+		if err := git.NewCommand(ctx, "checkout").AddDynamicArguments(baseBranch).
+			Run(&git.RunOpts{
+				Dir:    tmpBasePath,
+				Stdout: &outbuf,
+				Stderr: &errbuf,
+			}); err != nil {
+			log.Error("git checkout base prior to merge post staging rebase [%s:%s -> %s:%s]: %v\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+			return "", fmt.Errorf("git checkout base prior to merge post staging rebase  [%s:%s -> %s:%s]: %w\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+		}
+		outbuf.Reset()
+		errbuf.Reset()
+
+		cmd := git.NewCommand(ctx, "merge")
+		if mergeStyle == repo_model.MergeStyleRebase {
+			cmd.AddArguments("--ff-only")
+		} else {
+			cmd.AddArguments("--no-ff", "--no-commit")
+		}
+		cmd.AddDynamicArguments(stagingBranch)
+
+		// Prepare merge with commit
+		if err := runMergeCommand(pr, mergeStyle, cmd, tmpBasePath); err != nil {
+			log.Error("Unable to merge staging into base: %v", err)
+			return "", err
+		}
+		if mergeStyle == repo_model.MergeStyleRebaseMerge {
+			if err := commitAndSignNoAuthor(ctx, pr, message, signArgs, tmpBasePath, env); err != nil {
+				log.Error("Unable to make final commit: %v", err)
+				return "", err
+			}
+		}
 	case repo_model.MergeStyleSquash:
-		if err := doMergeStyleSquash(mergeCtx, message); err != nil {
+		// Merge with squash
+		cmd := git.NewCommand(ctx, "merge", "--squash").AddDynamicArguments(trackingBranch)
+		if err := runMergeCommand(pr, mergeStyle, cmd, tmpBasePath); err != nil {
+			log.Error("Unable to merge --squash tracking into base: %v", err)
 			return "", err
 		}
+
+		if err = pr.Issue.LoadPoster(ctx); err != nil {
+			log.Error("LoadPoster: %v", err)
+			return "", fmt.Errorf("LoadPoster: %w", err)
+		}
+		sig := pr.Issue.Poster.NewGitSig()
+		if setting.Repository.PullRequest.AddCoCommitterTrailers && committer.String() != sig.String() {
+			// add trailer
+			message += fmt.Sprintf("\nCo-authored-by: %s\nCo-committed-by: %s\n", sig.String(), sig.String())
+		}
+		if err := git.NewCommand(ctx, "commit").
+			AddArguments(signArgs...).
+			AddOptionFormat("--author='%s <%s>'", sig.Name, sig.Email).
+			AddOptionFormat("--message=%s", message).
+			Run(&git.RunOpts{
+				Env:    env,
+				Dir:    tmpBasePath,
+				Stdout: &outbuf,
+				Stderr: &errbuf,
+			}); err != nil {
+			log.Error("git commit [%s:%s -> %s:%s]: %v\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+			return "", fmt.Errorf("git commit [%s:%s -> %s:%s]: %w\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+		}
+		outbuf.Reset()
+		errbuf.Reset()
 	default:
 		return "", models.ErrInvalidMergeStyle{ID: pr.BaseRepo.ID, Style: mergeStyle}
 	}
 
 	// OK we should cache our current head and origin/headbranch
-	mergeHeadSHA, err := git.GetFullCommitID(ctx, mergeCtx.tmpBasePath, "HEAD")
+	mergeHeadSHA, err := git.GetFullCommitID(ctx, tmpBasePath, "HEAD")
 	if err != nil {
 		return "", fmt.Errorf("Failed to get full commit id for HEAD: %w", err)
 	}
-	mergeBaseSHA, err := git.GetFullCommitID(ctx, mergeCtx.tmpBasePath, "original_"+baseBranch)
+	mergeBaseSHA, err := git.GetFullCommitID(ctx, tmpBasePath, "original_"+baseBranch)
 	if err != nil {
 		return "", fmt.Errorf("Failed to get full commit id for origin/%s: %w", pr.BaseBranch, err)
 	}
-	mergeCommitID, err := git.GetFullCommitID(ctx, mergeCtx.tmpBasePath, baseBranch)
+	mergeCommitID, err := git.GetFullCommitID(ctx, tmpBasePath, baseBranch)
 	if err != nil {
 		return "", fmt.Errorf("Failed to get full commit id for the new merge: %w", err)
 	}
@@ -277,7 +567,7 @@ func doMergeAndPush(ctx context.Context, pr *issues_model.PullRequest, doer *use
 	// I think in the interests of data safety - failures to push to the lfs should prevent
 	// the merge as you can always remerge.
 	if setting.LFS.StartServer {
-		if err := LFSPush(ctx, mergeCtx.tmpBasePath, mergeHeadSHA, mergeBaseSHA, pr); err != nil {
+		if err := LFSPush(ctx, tmpBasePath, mergeHeadSHA, mergeBaseSHA, pr); err != nil {
 			return "", err
 		}
 	}
@@ -286,92 +576,167 @@ func doMergeAndPush(ctx context.Context, pr *issues_model.PullRequest, doer *use
 	err = pr.HeadRepo.LoadOwner(ctx)
 	if err != nil {
 		if !user_model.IsErrUserNotExist(err) {
-			log.Error("Can't find user: %d for head repository in %-v: %v", pr.HeadRepo.OwnerID, pr, err)
+			log.Error("Can't find user: %d for head repository - %v", pr.HeadRepo.OwnerID, err)
 			return "", err
 		}
-		log.Warn("Can't find user: %d for head repository in %-v - defaulting to doer: %s - %v", pr.HeadRepo.OwnerID, pr, doer.Name, err)
+		log.Error("Can't find user: %d for head repository - defaulting to doer: %s - %v", pr.HeadRepo.OwnerID, doer.Name, err)
 		headUser = doer
 	} else {
 		headUser = pr.HeadRepo.Owner
 	}
 
-	mergeCtx.env = repo_module.FullPushingEnvironment(
-		headUser,
-		doer,
-		pr.BaseRepo,
-		pr.BaseRepo.Name,
-		pr.ID,
-	)
-	pushCmd := git.NewCommand(ctx, "push", "origin").AddDynamicArguments(baseBranch + ":" + git.BranchPrefix + pr.BaseBranch)
+	var pushCmd *git.Command
+	if mergeStyle == repo_model.MergeStyleRebaseUpdate {
+		// force push the rebase result to head branch
+		env = repo_module.FullPushingEnvironment(
+			headUser,
+			doer,
+			pr.HeadRepo,
+			pr.HeadRepo.Name,
+			pr.ID,
+		)
+		pushCmd = git.NewCommand(ctx, "push", "-f", "head_repo").AddDynamicArguments(stagingBranch + ":" + git.BranchPrefix + pr.HeadBranch)
+	} else {
+		env = repo_module.FullPushingEnvironment(
+			headUser,
+			doer,
+			pr.BaseRepo,
+			pr.BaseRepo.Name,
+			pr.ID,
+		)
+		pushCmd = git.NewCommand(ctx, "push", "origin").AddDynamicArguments(baseBranch + ":" + git.BranchPrefix + pr.BaseBranch)
+	}
 
 	// Push back to upstream.
 	// TODO: this cause an api call to "/api/internal/hook/post-receive/...",
 	//       that prevents us from doint the whole merge in one db transaction
-	if err := pushCmd.Run(mergeCtx.RunOpts()); err != nil {
-		if strings.Contains(mergeCtx.errbuf.String(), "non-fast-forward") {
+	if err := pushCmd.Run(&git.RunOpts{
+		Env:    env,
+		Dir:    tmpBasePath,
+		Stdout: &outbuf,
+		Stderr: &errbuf,
+	}); err != nil {
+		if strings.Contains(errbuf.String(), "non-fast-forward") {
 			return "", &git.ErrPushOutOfDate{
-				StdOut: mergeCtx.outbuf.String(),
-				StdErr: mergeCtx.errbuf.String(),
+				StdOut: outbuf.String(),
+				StdErr: errbuf.String(),
 				Err:    err,
 			}
-		} else if strings.Contains(mergeCtx.errbuf.String(), "! [remote rejected]") {
+		} else if strings.Contains(errbuf.String(), "! [remote rejected]") {
 			err := &git.ErrPushRejected{
-				StdOut: mergeCtx.outbuf.String(),
-				StdErr: mergeCtx.errbuf.String(),
+				StdOut: outbuf.String(),
+				StdErr: errbuf.String(),
 				Err:    err,
 			}
 			err.GenerateMessage()
 			return "", err
 		}
-		return "", fmt.Errorf("git push: %s", mergeCtx.errbuf.String())
+		return "", fmt.Errorf("git push: %s", errbuf.String())
 	}
-	mergeCtx.outbuf.Reset()
-	mergeCtx.errbuf.Reset()
+	outbuf.Reset()
+	errbuf.Reset()
 
 	return mergeCommitID, nil
 }
 
-func commitAndSignNoAuthor(ctx *mergeContext, message string) error {
-	if err := git.NewCommand(ctx, "commit").AddArguments(ctx.signArg...).AddOptionFormat("--message=%s", message).
-		Run(ctx.RunOpts()); err != nil {
-		log.Error("git commit %-v: %v\n%s\n%s", ctx.pr, err, ctx.outbuf.String(), ctx.errbuf.String())
-		return fmt.Errorf("git commit %v: %w\n%s\n%s", ctx.pr, err, ctx.outbuf.String(), ctx.errbuf.String())
+func commitAndSignNoAuthor(ctx context.Context, pr *issues_model.PullRequest, message string, signArgs git.TrustedCmdArgs, tmpBasePath string, env []string) error {
+	var outbuf, errbuf strings.Builder
+	if err := git.NewCommand(ctx, "commit").AddArguments(signArgs...).AddOptionFormat("--message=%s", message).
+		Run(&git.RunOpts{
+			Env:    env,
+			Dir:    tmpBasePath,
+			Stdout: &outbuf,
+			Stderr: &errbuf,
+		}); err != nil {
+		log.Error("git commit [%s:%s -> %s:%s]: %v\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+		return fmt.Errorf("git commit [%s:%s -> %s:%s]: %w\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
 	}
 	return nil
 }
 
-func runMergeCommand(ctx *mergeContext, mergeStyle repo_model.MergeStyle, cmd *git.Command) error {
-	if err := cmd.Run(ctx.RunOpts()); err != nil {
+func runMergeCommand(pr *issues_model.PullRequest, mergeStyle repo_model.MergeStyle, cmd *git.Command, tmpBasePath string) error {
+	var outbuf, errbuf strings.Builder
+	if err := cmd.Run(&git.RunOpts{
+		Dir:    tmpBasePath,
+		Stdout: &outbuf,
+		Stderr: &errbuf,
+	}); err != nil {
 		// Merge will leave a MERGE_HEAD file in the .git folder if there is a conflict
-		if _, statErr := os.Stat(filepath.Join(ctx.tmpBasePath, ".git", "MERGE_HEAD")); statErr == nil {
+		if _, statErr := os.Stat(filepath.Join(tmpBasePath, ".git", "MERGE_HEAD")); statErr == nil {
 			// We have a merge conflict error
-			log.Debug("MergeConflict %-v: %v\n%s\n%s", ctx.pr, err, ctx.outbuf.String(), ctx.errbuf.String())
+			log.Debug("MergeConflict [%s:%s -> %s:%s]: %v\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
 			return models.ErrMergeConflicts{
 				Style:  mergeStyle,
-				StdOut: ctx.outbuf.String(),
-				StdErr: ctx.errbuf.String(),
+				StdOut: outbuf.String(),
+				StdErr: errbuf.String(),
 				Err:    err,
 			}
-		} else if strings.Contains(ctx.errbuf.String(), "refusing to merge unrelated histories") {
-			log.Debug("MergeUnrelatedHistories %-v: %v\n%s\n%s", ctx.pr, err, ctx.outbuf.String(), ctx.errbuf.String())
+		} else if strings.Contains(errbuf.String(), "refusing to merge unrelated histories") {
+			log.Debug("MergeUnrelatedHistories [%s:%s -> %s:%s]: %v\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
 			return models.ErrMergeUnrelatedHistories{
 				Style:  mergeStyle,
-				StdOut: ctx.outbuf.String(),
-				StdErr: ctx.errbuf.String(),
+				StdOut: outbuf.String(),
+				StdErr: errbuf.String(),
 				Err:    err,
 			}
 		}
-		log.Error("git merge %-v: %v\n%s\n%s", ctx.pr, err, ctx.outbuf.String(), ctx.errbuf.String())
-		return fmt.Errorf("git merge %v: %w\n%s\n%s", ctx.pr, err, ctx.outbuf.String(), ctx.errbuf.String())
+		log.Error("git merge [%s:%s -> %s:%s]: %v\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
+		return fmt.Errorf("git merge [%s:%s -> %s:%s]: %w\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
 	}
-	ctx.outbuf.Reset()
-	ctx.errbuf.Reset()
 
 	return nil
 }
 
 var escapedSymbols = regexp.MustCompile(`([*[?! \\])`)
 
+func getDiffTree(ctx context.Context, repoPath, baseBranch, headBranch string) (string, error) {
+	getDiffTreeFromBranch := func(repoPath, baseBranch, headBranch string) (string, error) {
+		var outbuf, errbuf strings.Builder
+		// Compute the diff-tree for sparse-checkout
+		if err := git.NewCommand(ctx, "diff-tree", "--no-commit-id", "--name-only", "-r", "-z", "--root").AddDynamicArguments(baseBranch, headBranch).
+			Run(&git.RunOpts{
+				Dir:    repoPath,
+				Stdout: &outbuf,
+				Stderr: &errbuf,
+			}); err != nil {
+			return "", fmt.Errorf("git diff-tree [%s base:%s head:%s]: %s", repoPath, baseBranch, headBranch, errbuf.String())
+		}
+		return outbuf.String(), nil
+	}
+
+	scanNullTerminatedStrings := func(data []byte, atEOF bool) (advance int, token []byte, err error) {
+		if atEOF && len(data) == 0 {
+			return 0, nil, nil
+		}
+		if i := bytes.IndexByte(data, '\x00'); i >= 0 {
+			return i + 1, data[0:i], nil
+		}
+		if atEOF {
+			return len(data), data, nil
+		}
+		return 0, nil, nil
+	}
+
+	list, err := getDiffTreeFromBranch(repoPath, baseBranch, headBranch)
+	if err != nil {
+		return "", err
+	}
+
+	// Prefixing '/' for each entry, otherwise all files with the same name in subdirectories would be matched.
+	out := bytes.Buffer{}
+	scanner := bufio.NewScanner(strings.NewReader(list))
+	scanner.Split(scanNullTerminatedStrings)
+	for scanner.Scan() {
+		filepath := scanner.Text()
+		// escape '*', '?', '[', spaces and '!' prefix
+		filepath = escapedSymbols.ReplaceAllString(filepath, `\$1`)
+		// no necessary to escape the first '#' symbol because the first symbol is '/'
+		fmt.Fprintf(&out, "/%s\n", filepath)
+	}
+
+	return out.String(), nil
+}
+
 // IsUserAllowedToMerge check if user is allowed to merge PR with given permissions and branch protections
 func IsUserAllowedToMerge(ctx context.Context, pr *issues_model.PullRequest, p access_model.Permission, user *user_model.User) (bool, error) {
 	if user == nil {

services/pull/merge_merge.go

@@ -1,25 +0,0 @@
-// Copyright 2023 The Gitea Authors. All rights reserved.
-// SPDX-License-Identifier: MIT
-
-package pull
-
-import (
-	repo_model "code.gitea.io/gitea/models/repo"
-	"code.gitea.io/gitea/modules/git"
-	"code.gitea.io/gitea/modules/log"
-)
-
-// doMergeStyleMerge merges the tracking into the current HEAD - which is assumed to tbe staging branch (equal to the pr.BaseBranch)
-func doMergeStyleMerge(ctx *mergeContext, message string) error {
-	cmd := git.NewCommand(ctx, "merge", "--no-ff", "--no-commit").AddDynamicArguments(trackingBranch)
-	if err := runMergeCommand(ctx, repo_model.MergeStyleMerge, cmd); err != nil {
-		log.Error("%-v Unable to merge tracking into base: %v", ctx.pr, err)
-		return err
-	}
-
-	if err := commitAndSignNoAuthor(ctx, message); err != nil {
-		log.Error("%-v Unable to make final commit: %v", ctx.pr, err)
-		return err
-	}
-	return nil
-}

services/pull/merge_prepare.go

@@ -1,297 +0,0 @@
-// Copyright 2023 The Gitea Authors. All rights reserved.
-// SPDX-License-Identifier: MIT
-
-package pull
-
-import (
-	"bufio"
-	"bytes"
-	"context"
-	"fmt"
-	"io"
-	"os"
-	"path/filepath"
-	"strings"
-	"time"
-
-	"code.gitea.io/gitea/models"
-	issues_model "code.gitea.io/gitea/models/issues"
-	repo_model "code.gitea.io/gitea/models/repo"
-	user_model "code.gitea.io/gitea/models/user"
-	"code.gitea.io/gitea/modules/git"
-	"code.gitea.io/gitea/modules/log"
-	asymkey_service "code.gitea.io/gitea/services/asymkey"
-)
-
-type mergeContext struct {
-	*prContext
-	doer      *user_model.User
-	sig       *git.Signature
-	committer *git.Signature
-	signArg   git.TrustedCmdArgs
-	env       []string
-}
-
-func (ctx *mergeContext) RunOpts() *git.RunOpts {
-	ctx.outbuf.Reset()
-	ctx.errbuf.Reset()
-	return &git.RunOpts{
-		Env:    ctx.env,
-		Dir:    ctx.tmpBasePath,
-		Stdout: ctx.outbuf,
-		Stderr: ctx.errbuf,
-	}
-}
-
-func createTemporaryRepoForMerge(ctx context.Context, pr *issues_model.PullRequest, doer *user_model.User, expectedHeadCommitID string) (mergeCtx *mergeContext, cancel context.CancelFunc, err error) {
-	// Clone base repo.
-	prCtx, cancel, err := createTemporaryRepoForPR(ctx, pr)
-	if err != nil {
-		log.Error("createTemporaryRepoForPR: %v", err)
-		return nil, cancel, err
-	}
-
-	mergeCtx = &mergeContext{
-		prContext: prCtx,
-		doer:      doer,
-	}
-
-	if expectedHeadCommitID != "" {
-		trackingCommitID, _, err := git.NewCommand(ctx, "show-ref", "--hash").AddDynamicArguments(git.BranchPrefix + trackingBranch).RunStdString(&git.RunOpts{Dir: mergeCtx.tmpBasePath})
-		if err != nil {
-			defer cancel()
-			log.Error("failed to get sha of head branch in %-v: show-ref[%s] --hash refs/heads/tracking: %v", mergeCtx.pr, mergeCtx.tmpBasePath, err)
-			return nil, nil, fmt.Errorf("unable to get sha of head branch in %v %w", pr, err)
-		}
-		if strings.TrimSpace(trackingCommitID) != expectedHeadCommitID {
-			defer cancel()
-			return nil, nil, models.ErrSHADoesNotMatch{
-				GivenSHA:   expectedHeadCommitID,
-				CurrentSHA: trackingCommitID,
-			}
-		}
-	}
-
-	mergeCtx.outbuf.Reset()
-	mergeCtx.errbuf.Reset()
-	if err := prepareTemporaryRepoForMerge(mergeCtx); err != nil {
-		defer cancel()
-		return nil, nil, err
-	}
-
-	mergeCtx.sig = doer.NewGitSig()
-	mergeCtx.committer = mergeCtx.sig
-
-	// Determine if we should sign
-	sign, keyID, signer, _ := asymkey_service.SignMerge(ctx, mergeCtx.pr, mergeCtx.doer, mergeCtx.tmpBasePath, "HEAD", trackingBranch)
-	if sign {
-		mergeCtx.signArg = git.ToTrustedCmdArgs([]string{"-S" + keyID})
-		if pr.BaseRepo.GetTrustModel() == repo_model.CommitterTrustModel || pr.BaseRepo.GetTrustModel() == repo_model.CollaboratorCommitterTrustModel {
-			mergeCtx.committer = signer
-		}
-	} else {
-		mergeCtx.signArg = git.ToTrustedCmdArgs([]string{"--no-gpg-sign"})
-	}
-
-	commitTimeStr := time.Now().Format(time.RFC3339)
-
-	// Because this may call hooks we should pass in the environment
-	mergeCtx.env = append(os.Environ(),
-		"GIT_AUTHOR_NAME="+mergeCtx.sig.Name,
-		"GIT_AUTHOR_EMAIL="+mergeCtx.sig.Email,
-		"GIT_AUTHOR_DATE="+commitTimeStr,
-		"GIT_COMMITTER_NAME="+mergeCtx.committer.Name,
-		"GIT_COMMITTER_EMAIL="+mergeCtx.committer.Email,
-		"GIT_COMMITTER_DATE="+commitTimeStr,
-	)
-
-	return mergeCtx, cancel, nil
-}
-
-// prepareTemporaryRepoForMerge takes a repository that has been created using createTemporaryRepo
-// it then sets up the sparse-checkout and other things
-func prepareTemporaryRepoForMerge(ctx *mergeContext) error {
-	infoPath := filepath.Join(ctx.tmpBasePath, ".git", "info")
-	if err := os.MkdirAll(infoPath, 0o700); err != nil {
-		log.Error("%-v Unable to create .git/info in %s: %v", ctx.pr, ctx.tmpBasePath, err)
-		return fmt.Errorf("Unable to create .git/info in tmpBasePath: %w", err)
-	}
-
-	// Enable sparse-checkout
-	// Here we use the .git/info/sparse-checkout file as described in the git documentation
-	sparseCheckoutListFile, err := os.OpenFile(filepath.Join(infoPath, "sparse-checkout"), os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0o600)
-	if err != nil {
-		log.Error("%-v Unable to write .git/info/sparse-checkout file in %s: %v", ctx.pr, ctx.tmpBasePath, err)
-		return fmt.Errorf("Unable to write .git/info/sparse-checkout file in tmpBasePath: %w", err)
-	}
-	defer sparseCheckoutListFile.Close() // we will close it earlier but we need to ensure it is closed if there is an error
-
-	if err := getDiffTree(ctx, ctx.tmpBasePath, baseBranch, trackingBranch, sparseCheckoutListFile); err != nil {
-		log.Error("%-v getDiffTree(%s, %s, %s): %v", ctx.pr, ctx.tmpBasePath, baseBranch, trackingBranch, err)
-		return fmt.Errorf("getDiffTree: %w", err)
-	}
-
-	if err := sparseCheckoutListFile.Close(); err != nil {
-		log.Error("%-v Unable to close .git/info/sparse-checkout file in %s: %v", ctx.pr, ctx.tmpBasePath, err)
-		return fmt.Errorf("Unable to close .git/info/sparse-checkout file in tmpBasePath: %w", err)
-	}
-
-	gitConfigCommand := func() *git.Command {
-		return git.NewCommand(ctx, "config", "--local")
-	}
-
-	setConfig := func(key, value string) error {
-		if err := gitConfigCommand().AddArguments(git.ToTrustedCmdArgs([]string{key, value})...).
-			Run(ctx.RunOpts()); err != nil {
-			if value == "" {
-				value = "<>"
-			}
-			log.Error("git config [%s -> %s ]: %v\n%s\n%s", key, value, err, ctx.outbuf.String(), ctx.errbuf.String())
-			return fmt.Errorf("git config [%s -> %s ]: %w\n%s\n%s", key, value, err, ctx.outbuf.String(), ctx.errbuf.String())
-		}
-		ctx.outbuf.Reset()
-		ctx.errbuf.Reset()
-
-		return nil
-	}
-
-	// Switch off LFS process (set required, clean and smudge here also)
-	if err := setConfig("filter.lfs.process", ""); err != nil {
-		return err
-	}
-
-	if err := setConfig("filter.lfs.required", "false"); err != nil {
-		return err
-	}
-
-	if err := setConfig("filter.lfs.clean", ""); err != nil {
-		return err
-	}
-
-	if err := setConfig("filter.lfs.smudge", ""); err != nil {
-		return err
-	}
-
-	if err := setConfig("core.sparseCheckout", "true"); err != nil {
-		return err
-	}
-
-	// Read base branch index
-	if err := git.NewCommand(ctx, "read-tree", "HEAD").
-		Run(ctx.RunOpts()); err != nil {
-		log.Error("git read-tree HEAD: %v\n%s\n%s", err, ctx.outbuf.String(), ctx.errbuf.String())
-		return fmt.Errorf("Unable to read base branch in to the index: %w\n%s\n%s", err, ctx.outbuf.String(), ctx.errbuf.String())
-	}
-	ctx.outbuf.Reset()
-	ctx.errbuf.Reset()
-
-	return nil
-}
-
-// getDiffTree returns a string containing all the files that were changed between headBranch and baseBranch
-// the filenames are escaped so as to fit the format required for .git/info/sparse-checkout
-func getDiffTree(ctx context.Context, repoPath, baseBranch, headBranch string, out io.Writer) error {
-	diffOutReader, diffOutWriter, err := os.Pipe()
-	if err != nil {
-		log.Error("Unable to create os.Pipe for %s", repoPath)
-		return err
-	}
-	defer func() {
-		_ = diffOutReader.Close()
-		_ = diffOutWriter.Close()
-	}()
-
-	scanNullTerminatedStrings := func(data []byte, atEOF bool) (advance int, token []byte, err error) {
-		if atEOF && len(data) == 0 {
-			return 0, nil, nil
-		}
-		if i := bytes.IndexByte(data, '\x00'); i >= 0 {
-			return i + 1, data[0:i], nil
-		}
-		if atEOF {
-			return len(data), data, nil
-		}
-		return 0, nil, nil
-	}
-
-	err = git.NewCommand(ctx, "diff-tree", "--no-commit-id", "--name-only", "-r", "-r", "-z", "--root").AddDynamicArguments(baseBranch, headBranch).
-		Run(&git.RunOpts{
-			Dir:    repoPath,
-			Stdout: diffOutWriter,
-			PipelineFunc: func(ctx context.Context, cancel context.CancelFunc) error {
-				// Close the writer end of the pipe to begin processing
-				_ = diffOutWriter.Close()
-				defer func() {
-					// Close the reader on return to terminate the git command if necessary
-					_ = diffOutReader.Close()
-				}()
-
-				// Now scan the output from the command
-				scanner := bufio.NewScanner(diffOutReader)
-				scanner.Split(scanNullTerminatedStrings)
-				for scanner.Scan() {
-					filepath := scanner.Text()
-					// escape '*', '?', '[', spaces and '!' prefix
-					filepath = escapedSymbols.ReplaceAllString(filepath, `\$1`)
-					// no necessary to escape the first '#' symbol because the first symbol is '/'
-					fmt.Fprintf(out, "/%s\n", filepath)
-				}
-				return scanner.Err()
-			},
-		})
-	return err
-}
-
-// rebaseTrackingOnToBase checks out the tracking branch as staging and rebases it on to the base branch
-// if there is a conflict it will return a models.ErrRebaseConflicts
-func rebaseTrackingOnToBase(ctx *mergeContext, mergeStyle repo_model.MergeStyle) error {
-	// Checkout head branch
-	if err := git.NewCommand(ctx, "checkout", "-b").AddDynamicArguments(stagingBranch, trackingBranch).
-		Run(ctx.RunOpts()); err != nil {
-		return fmt.Errorf("unable to git checkout tracking as staging in temp repo for %v: %w\n%s\n%s", ctx.pr, err, ctx.outbuf.String(), ctx.errbuf.String())
-	}
-	ctx.outbuf.Reset()
-	ctx.errbuf.Reset()
-
-	// Rebase before merging
-	if err := git.NewCommand(ctx, "rebase").AddDynamicArguments(baseBranch).
-		Run(ctx.RunOpts()); err != nil {
-		// Rebase will leave a REBASE_HEAD file in .git if there is a conflict
-		if _, statErr := os.Stat(filepath.Join(ctx.tmpBasePath, ".git", "REBASE_HEAD")); statErr == nil {
-			var commitSha string
-			ok := false
-			failingCommitPaths := []string{
-				filepath.Join(ctx.tmpBasePath, ".git", "rebase-apply", "original-commit"), // Git < 2.26
-				filepath.Join(ctx.tmpBasePath, ".git", "rebase-merge", "stopped-sha"),     // Git >= 2.26
-			}
-			for _, failingCommitPath := range failingCommitPaths {
-				if _, statErr := os.Stat(failingCommitPath); statErr == nil {
-					commitShaBytes, readErr := os.ReadFile(failingCommitPath)
-					if readErr != nil {
-						// Abandon this attempt to handle the error
-						return fmt.Errorf("unable to git rebase staging on to base in temp repo for %v: %w\n%s\n%s", ctx.pr, err, ctx.outbuf.String(), ctx.errbuf.String())
-					}
-					commitSha = strings.TrimSpace(string(commitShaBytes))
-					ok = true
-					break
-				}
-			}
-			if !ok {
-				log.Error("Unable to determine failing commit sha for failing rebase in temp repo for %-v. Cannot cast as models.ErrRebaseConflicts.", ctx.pr)
-				return fmt.Errorf("unable to git rebase staging on to base in temp repo for %v: %w\n%s\n%s", ctx.pr, err, ctx.outbuf.String(), ctx.errbuf.String())
-			}
-			log.Debug("Conflict when rebasing staging on to base in %-v at %s: %v\n%s\n%s", ctx.pr, commitSha, err, ctx.outbuf.String(), ctx.errbuf.String())
-			return models.ErrRebaseConflicts{
-				CommitSHA: commitSha,
-				Style:     mergeStyle,
-				StdOut:    ctx.outbuf.String(),
-				StdErr:    ctx.errbuf.String(),
-				Err:       err,
-			}
-		}
-		return fmt.Errorf("unable to git rebase staging on to base in temp repo for %v: %w\n%s\n%s", ctx.pr, err, ctx.outbuf.String(), ctx.errbuf.String())
-	}
-	ctx.outbuf.Reset()
-	ctx.errbuf.Reset()
-	return nil
-}

services/pull/merge_rebase.go

@@ -1,50 +0,0 @@
-// Copyright 2023 The Gitea Authors. All rights reserved.
-// SPDX-License-Identifier: MIT
-
-package pull
-
-import (
-	"fmt"
-
-	repo_model "code.gitea.io/gitea/models/repo"
-	"code.gitea.io/gitea/modules/git"
-	"code.gitea.io/gitea/modules/log"
-)
-
-// doMergeStyleRebase rebaases the tracking branch on the base branch as the current HEAD with or with a merge commit to the original pr branch
-func doMergeStyleRebase(ctx *mergeContext, mergeStyle repo_model.MergeStyle, message string) error {
-	if err := rebaseTrackingOnToBase(ctx, mergeStyle); err != nil {
-		return err
-	}
-
-	// Checkout base branch again
-	if err := git.NewCommand(ctx, "checkout").AddDynamicArguments(baseBranch).
-		Run(ctx.RunOpts()); err != nil {
-		log.Error("git checkout base prior to merge post staging rebase %-v: %v\n%s\n%s", ctx.pr, err, ctx.outbuf.String(), ctx.errbuf.String())
-		return fmt.Errorf("git checkout base prior to merge post staging rebase  %v: %w\n%s\n%s", ctx.pr, err, ctx.outbuf.String(), ctx.errbuf.String())
-	}
-	ctx.outbuf.Reset()
-	ctx.errbuf.Reset()
-
-	cmd := git.NewCommand(ctx, "merge")
-	if mergeStyle == repo_model.MergeStyleRebase {
-		cmd.AddArguments("--ff-only")
-	} else {
-		cmd.AddArguments("--no-ff", "--no-commit")
-	}
-	cmd.AddDynamicArguments(stagingBranch)
-
-	// Prepare merge with commit
-	if err := runMergeCommand(ctx, mergeStyle, cmd); err != nil {
-		log.Error("Unable to merge staging into base: %v", err)
-		return err
-	}
-	if mergeStyle == repo_model.MergeStyleRebaseMerge {
-		if err := commitAndSignNoAuthor(ctx, message); err != nil {
-			log.Error("Unable to make final commit: %v", err)
-			return err
-		}
-	}
-
-	return nil
-}

services/pull/merge_squash.go

@@ -1,53 +0,0 @@
-// Copyright 2023 The Gitea Authors. All rights reserved.
-// SPDX-License-Identifier: MIT
-
-package pull
-
-import (
-	"fmt"
-
-	repo_model "code.gitea.io/gitea/models/repo"
-	"code.gitea.io/gitea/modules/git"
-	"code.gitea.io/gitea/modules/log"
-	"code.gitea.io/gitea/modules/setting"
-)
-
-// doMergeStyleSquash squashes the tracking branch on the current HEAD (=base)
-func doMergeStyleSquash(ctx *mergeContext, message string) error {
-	cmd := git.NewCommand(ctx, "merge", "--squash").AddDynamicArguments(trackingBranch)
-	if err := runMergeCommand(ctx, repo_model.MergeStyleSquash, cmd); err != nil {
-		log.Error("%-v Unable to merge --squash tracking into base: %v", ctx.pr, err)
-		return err
-	}
-
-	if err := ctx.pr.Issue.LoadPoster(ctx); err != nil {
-		log.Error("%-v Issue[%d].LoadPoster: %v", ctx.pr, ctx.pr.Issue.ID, err)
-		return fmt.Errorf("LoadPoster: %w", err)
-	}
-	sig := ctx.pr.Issue.Poster.NewGitSig()
-	if len(ctx.signArg) == 0 {
-		if err := git.NewCommand(ctx, "commit").
-			AddOptionFormat("--author='%s <%s>'", sig.Name, sig.Email).
-			AddOptionFormat("--message=%s", message).
-			Run(ctx.RunOpts()); err != nil {
-			log.Error("git commit %-v: %v\n%s\n%s", ctx.pr, err, ctx.outbuf.String(), ctx.errbuf.String())
-			return fmt.Errorf("git commit [%s:%s -> %s:%s]: %w\n%s\n%s", ctx.pr.HeadRepo.FullName(), ctx.pr.HeadBranch, ctx.pr.BaseRepo.FullName(), ctx.pr.BaseBranch, err, ctx.outbuf.String(), ctx.errbuf.String())
-		}
-	} else {
-		if setting.Repository.PullRequest.AddCoCommitterTrailers && ctx.committer.String() != sig.String() {
-			// add trailer
-			message += fmt.Sprintf("\nCo-authored-by: %s\nCo-committed-by: %s\n", sig.String(), sig.String())
-		}
-		if err := git.NewCommand(ctx, "commit").
-			AddArguments(ctx.signArg...).
-			AddOptionFormat("--author='%s <%s>'", sig.Name, sig.Email).
-			AddOptionFormat("--message=%s", message).
-			Run(ctx.RunOpts()); err != nil {
-			log.Error("git commit %-v: %v\n%s\n%s", ctx.pr, err, ctx.outbuf.String(), ctx.errbuf.String())
-			return fmt.Errorf("git commit [%s:%s -> %s:%s]: %w\n%s\n%s", ctx.pr.HeadRepo.FullName(), ctx.pr.HeadBranch, ctx.pr.BaseRepo.FullName(), ctx.pr.BaseBranch, err, ctx.outbuf.String(), ctx.errbuf.String())
-		}
-	}
-	ctx.outbuf.Reset()
-	ctx.errbuf.Reset()
-	return nil
-}

services/pull/patch.go

@@ -22,6 +22,7 @@ import (
 	"code.gitea.io/gitea/modules/graceful"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/process"
+	repo_module "code.gitea.io/gitea/modules/repository"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/util"
 
@@ -63,21 +64,25 @@ func TestPatch(pr *issues_model.PullRequest) error {
 	defer finished()
 
 	// Clone base repo.
-	prCtx, cancel, err := createTemporaryRepoForPR(ctx, pr)
+	tmpBasePath, err := createTemporaryRepo(ctx, pr)
 	if err != nil {
-		log.Error("createTemporaryRepoForPR %-v: %v", pr, err)
+		log.Error("CreateTemporaryPath: %v", err)
 		return err
 	}
-	defer cancel()
+	defer func() {
+		if err := repo_module.RemoveTemporaryPath(tmpBasePath); err != nil {
+			log.Error("Merge: RemoveTemporaryPath: %s", err)
+		}
+	}()
 
-	gitRepo, err := git.OpenRepository(ctx, prCtx.tmpBasePath)
+	gitRepo, err := git.OpenRepository(ctx, tmpBasePath)
 	if err != nil {
 		return fmt.Errorf("OpenRepository: %w", err)
 	}
 	defer gitRepo.Close()
 
 	// 1. update merge base
-	pr.MergeBase, _, err = git.NewCommand(ctx, "merge-base", "--", "base", "tracking").RunStdString(&git.RunOpts{Dir: prCtx.tmpBasePath})
+	pr.MergeBase, _, err = git.NewCommand(ctx, "merge-base", "--", "base", "tracking").RunStdString(&git.RunOpts{Dir: tmpBasePath})
 	if err != nil {
 		var err2 error
 		pr.MergeBase, err2 = gitRepo.GetRefCommitID(git.BranchPrefix + "base")
@@ -96,7 +101,7 @@ func TestPatch(pr *issues_model.PullRequest) error {
 	}
 
 	// 2. Check for conflicts
-	if conflicts, err := checkConflicts(ctx, pr, gitRepo, prCtx.tmpBasePath); err != nil || conflicts || pr.Status == issues_model.PullRequestStatusEmpty {
+	if conflicts, err := checkConflicts(ctx, pr, gitRepo, tmpBasePath); err != nil || conflicts || pr.Status == issues_model.PullRequestStatusEmpty {
 		return err
 	}
 

services/pull/pull.go

@@ -349,14 +349,18 @@ func AddTestPullRequestTask(doer *user_model.User, repoID int64, branch string,
 // checkIfPRContentChanged checks if diff to target branch has changed by push
 // A commit can be considered to leave the PR untouched if the patch/diff with its merge base is unchanged
 func checkIfPRContentChanged(ctx context.Context, pr *issues_model.PullRequest, oldCommitID, newCommitID string) (hasChanged bool, err error) {
-	prCtx, cancel, err := createTemporaryRepoForPR(ctx, pr)
+	tmpBasePath, err := createTemporaryRepo(ctx, pr)
 	if err != nil {
-		log.Error("CreateTemporaryRepoForPR %-v: %v", pr, err)
+		log.Error("CreateTemporaryRepo: %v", err)
 		return false, err
 	}
-	defer cancel()
+	defer func() {
+		if err := repo_module.RemoveTemporaryPath(tmpBasePath); err != nil {
+			log.Error("checkIfPRContentChanged: RemoveTemporaryPath: %s", err)
+		}
+	}()
 
-	tmpRepo, err := git.OpenRepository(ctx, prCtx.tmpBasePath)
+	tmpRepo, err := git.OpenRepository(ctx, tmpBasePath)
 	if err != nil {
 		return false, fmt.Errorf("OpenRepository: %w", err)
 	}
@@ -375,7 +379,7 @@ func checkIfPRContentChanged(ctx context.Context, pr *issues_model.PullRequest,
 	}
 
 	if err := cmd.Run(&git.RunOpts{
-		Dir:    prCtx.tmpBasePath,
+		Dir:    tmpBasePath,
 		Stdout: stdoutWriter,
 		PipelineFunc: func(ctx context.Context, cancel context.CancelFunc) error {
 			_ = stdoutWriter.Close()

services/pull/temp_repo.go

@@ -19,85 +19,49 @@ import (
 	repo_module "code.gitea.io/gitea/modules/repository"
 )
 
-// Temporary repos created here use standard branch names to help simplify
-// merging code
-const (
-	baseBranch     = "base"     // equivalent to pr.BaseBranch
-	trackingBranch = "tracking" // equivalent to pr.HeadBranch
-	stagingBranch  = "staging"  // this is used for a working branch
-)
-
-type prContext struct {
-	context.Context
-	tmpBasePath string
-	pr          *issues_model.PullRequest
-	outbuf      *strings.Builder // we keep these around to help reduce needless buffer recreation,
-	errbuf      *strings.Builder // any use should be preceded by a Reset and preferably after use
-}
-
-func (ctx *prContext) RunOpts() *git.RunOpts {
-	ctx.outbuf.Reset()
-	ctx.errbuf.Reset()
-	return &git.RunOpts{
-		Dir:    ctx.tmpBasePath,
-		Stdout: ctx.outbuf,
-		Stderr: ctx.errbuf,
-	}
-}
-
-// createTemporaryRepoForPR creates a temporary repo with "base" for pr.BaseBranch and "tracking" for  pr.HeadBranch
+// createTemporaryRepo creates a temporary repo with "base" for pr.BaseBranch and "tracking" for  pr.HeadBranch
 // it also create a second base branch called "original_base"
-func createTemporaryRepoForPR(ctx context.Context, pr *issues_model.PullRequest) (prCtx *prContext, cancel context.CancelFunc, err error) {
+func createTemporaryRepo(ctx context.Context, pr *issues_model.PullRequest) (string, error) {
 	if err := pr.LoadHeadRepo(ctx); err != nil {
-		log.Error("%-v LoadHeadRepo: %v", pr, err)
-		return nil, nil, fmt.Errorf("%v LoadHeadRepo: %w", pr, err)
+		log.Error("LoadHeadRepo: %v", err)
+		return "", fmt.Errorf("LoadHeadRepo: %w", err)
 	} else if pr.HeadRepo == nil {
-		log.Error("%-v HeadRepo %d does not exist", pr, pr.HeadRepoID)
-		return nil, nil, &repo_model.ErrRepoNotExist{
+		log.Error("Pr %d HeadRepo %d does not exist", pr.ID, pr.HeadRepoID)
+		return "", &repo_model.ErrRepoNotExist{
 			ID: pr.HeadRepoID,
 		}
 	} else if err := pr.LoadBaseRepo(ctx); err != nil {
-		log.Error("%-v LoadBaseRepo: %v", pr, err)
-		return nil, nil, fmt.Errorf("%v LoadBaseRepo: %w", pr, err)
+		log.Error("LoadBaseRepo: %v", err)
+		return "", fmt.Errorf("LoadBaseRepo: %w", err)
 	} else if pr.BaseRepo == nil {
-		log.Error("%-v BaseRepo %d does not exist", pr, pr.BaseRepoID)
-		return nil, nil, &repo_model.ErrRepoNotExist{
+		log.Error("Pr %d BaseRepo %d does not exist", pr.ID, pr.BaseRepoID)
+		return "", &repo_model.ErrRepoNotExist{
 			ID: pr.BaseRepoID,
 		}
 	} else if err := pr.HeadRepo.LoadOwner(ctx); err != nil {
-		log.Error("%-v HeadRepo.LoadOwner: %v", pr, err)
-		return nil, nil, fmt.Errorf("%v HeadRepo.LoadOwner: %w", pr, err)
+		log.Error("HeadRepo.LoadOwner: %v", err)
+		return "", fmt.Errorf("HeadRepo.LoadOwner: %w", err)
 	} else if err := pr.BaseRepo.LoadOwner(ctx); err != nil {
-		log.Error("%-v BaseRepo.LoadOwner: %v", pr, err)
-		return nil, nil, fmt.Errorf("%v BaseRepo.LoadOwner: %w", pr, err)
+		log.Error("BaseRepo.LoadOwner: %v", err)
+		return "", fmt.Errorf("BaseRepo.LoadOwner: %w", err)
 	}
 
 	// Clone base repo.
 	tmpBasePath, err := repo_module.CreateTemporaryPath("pull")
 	if err != nil {
-		log.Error("CreateTemporaryPath[%-v]: %v", pr, err)
-		return nil, nil, err
-	}
-	prCtx = &prContext{
-		Context:     ctx,
-		tmpBasePath: tmpBasePath,
-		pr:          pr,
-		outbuf:      &strings.Builder{},
-		errbuf:      &strings.Builder{},
-	}
-	cancel = func() {
-		if err := repo_module.RemoveTemporaryPath(tmpBasePath); err != nil {
-			log.Error("Error whilst removing removing temporary repo for %-v: %v", pr, err)
-		}
+		log.Error("CreateTemporaryPath: %v", err)
+		return "", err
 	}
 
 	baseRepoPath := pr.BaseRepo.RepoPath()
 	headRepoPath := pr.HeadRepo.RepoPath()
 
 	if err := git.InitRepository(ctx, tmpBasePath, false); err != nil {
-		log.Error("Unable to init tmpBasePath for %-v: %v", pr, err)
-		cancel()
-		return nil, nil, err
+		log.Error("git init tmpBasePath: %v", err)
+		if err := repo_module.RemoveTemporaryPath(tmpBasePath); err != nil {
+			log.Error("CreateTempRepo: RemoveTemporaryPath: %s", err)
+		}
+		return "", err
 	}
 
 	remoteRepoName := "head_repo"
@@ -109,63 +73,99 @@ func createTemporaryRepoForPR(ctx context.Context, pr *issues_model.PullRequest)
 		fetchArgs = append(fetchArgs, "--no-write-commit-graph")
 	}
 
-	// addCacheRepo adds git alternatives for the cacheRepoPath in the repoPath
-	addCacheRepo := func(repoPath, cacheRepoPath string) error {
-		p := filepath.Join(repoPath, ".git", "objects", "info", "alternates")
+	// Add head repo remote.
+	addCacheRepo := func(staging, cache string) error {
+		p := filepath.Join(staging, ".git", "objects", "info", "alternates")
 		f, err := os.OpenFile(p, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0o600)
 		if err != nil {
-			log.Error("Could not create .git/objects/info/alternates file in %s: %v", repoPath, err)
+			log.Error("Could not create .git/objects/info/alternates file in %s: %v", staging, err)
 			return err
 		}
 		defer f.Close()
-		data := filepath.Join(cacheRepoPath, "objects")
+		data := filepath.Join(cache, "objects")
 		if _, err := fmt.Fprintln(f, data); err != nil {
-			log.Error("Could not write to .git/objects/info/alternates file in %s: %v", repoPath, err)
+			log.Error("Could not write to .git/objects/info/alternates file in %s: %v", staging, err)
 			return err
 		}
 		return nil
 	}
 
-	// Add head repo remote.
 	if err := addCacheRepo(tmpBasePath, baseRepoPath); err != nil {
-		log.Error("%-v Unable to add base repository to temporary repo [%s -> %s]: %v", pr, pr.BaseRepo.FullName(), tmpBasePath, err)
-		cancel()
-		return nil, nil, fmt.Errorf("Unable to add base repository to temporary repo [%s -> tmpBasePath]: %w", pr.BaseRepo.FullName(), err)
+		log.Error("Unable to add base repository to temporary repo [%s -> %s]: %v", pr.BaseRepo.FullName(), tmpBasePath, err)
+		if err := repo_module.RemoveTemporaryPath(tmpBasePath); err != nil {
+			log.Error("CreateTempRepo: RemoveTemporaryPath: %s", err)
+		}
+		return "", fmt.Errorf("Unable to add base repository to temporary repo [%s -> tmpBasePath]: %w", pr.BaseRepo.FullName(), err)
 	}
 
+	var outbuf, errbuf strings.Builder
 	if err := git.NewCommand(ctx, "remote", "add", "-t").AddDynamicArguments(pr.BaseBranch).AddArguments("-m").AddDynamicArguments(pr.BaseBranch).AddDynamicArguments("origin", baseRepoPath).
-		Run(prCtx.RunOpts()); err != nil {
-		log.Error("%-v Unable to add base repository as origin [%s -> %s]: %v\n%s\n%s", pr, pr.BaseRepo.FullName(), tmpBasePath, err, prCtx.outbuf.String(), prCtx.errbuf.String())
-		cancel()
-		return nil, nil, fmt.Errorf("Unable to add base repository as origin [%s -> tmpBasePath]: %w\n%s\n%s", pr.BaseRepo.FullName(), err, prCtx.outbuf.String(), prCtx.errbuf.String())
+		Run(&git.RunOpts{
+			Dir:    tmpBasePath,
+			Stdout: &outbuf,
+			Stderr: &errbuf,
+		}); err != nil {
+		log.Error("Unable to add base repository as origin [%s -> %s]: %v\n%s\n%s", pr.BaseRepo.FullName(), tmpBasePath, err, outbuf.String(), errbuf.String())
+		if err := repo_module.RemoveTemporaryPath(tmpBasePath); err != nil {
+			log.Error("CreateTempRepo: RemoveTemporaryPath: %s", err)
+		}
+		return "", fmt.Errorf("Unable to add base repository as origin [%s -> tmpBasePath]: %w\n%s\n%s", pr.BaseRepo.FullName(), err, outbuf.String(), errbuf.String())
 	}
+	outbuf.Reset()
+	errbuf.Reset()
 
 	if err := git.NewCommand(ctx, "fetch", "origin").AddArguments(fetchArgs...).AddDashesAndList(pr.BaseBranch+":"+baseBranch, pr.BaseBranch+":original_"+baseBranch).
-		Run(prCtx.RunOpts()); err != nil {
-		log.Error("%-v Unable to fetch origin base branch [%s:%s -> base, original_base in %s]: %v:\n%s\n%s", pr, pr.BaseRepo.FullName(), pr.BaseBranch, tmpBasePath, err, prCtx.outbuf.String(), prCtx.errbuf.String())
-		cancel()
-		return nil, nil, fmt.Errorf("Unable to fetch origin base branch [%s:%s -> base, original_base in tmpBasePath]: %w\n%s\n%s", pr.BaseRepo.FullName(), pr.BaseBranch, err, prCtx.outbuf.String(), prCtx.errbuf.String())
+		Run(&git.RunOpts{
+			Dir:    tmpBasePath,
+			Stdout: &outbuf,
+			Stderr: &errbuf,
+		}); err != nil {
+		log.Error("Unable to fetch origin base branch [%s:%s -> base, original_base in %s]: %v:\n%s\n%s", pr.BaseRepo.FullName(), pr.BaseBranch, tmpBasePath, err, outbuf.String(), errbuf.String())
+		if err := repo_module.RemoveTemporaryPath(tmpBasePath); err != nil {
+			log.Error("CreateTempRepo: RemoveTemporaryPath: %s", err)
+		}
+		return "", fmt.Errorf("Unable to fetch origin base branch [%s:%s -> base, original_base in tmpBasePath]: %w\n%s\n%s", pr.BaseRepo.FullName(), pr.BaseBranch, err, outbuf.String(), errbuf.String())
 	}
+	outbuf.Reset()
+	errbuf.Reset()
 
 	if err := git.NewCommand(ctx, "symbolic-ref").AddDynamicArguments("HEAD", git.BranchPrefix+baseBranch).
-		Run(prCtx.RunOpts()); err != nil {
-		log.Error("%-v Unable to set HEAD as base branch in [%s]: %v\n%s\n%s", pr, tmpBasePath, err, prCtx.outbuf.String(), prCtx.errbuf.String())
-		cancel()
-		return nil, nil, fmt.Errorf("Unable to set HEAD as base branch in tmpBasePath: %w\n%s\n%s", err, prCtx.outbuf.String(), prCtx.errbuf.String())
+		Run(&git.RunOpts{
+			Dir:    tmpBasePath,
+			Stdout: &outbuf,
+			Stderr: &errbuf,
+		}); err != nil {
+		log.Error("Unable to set HEAD as base branch [%s]: %v\n%s\n%s", tmpBasePath, err, outbuf.String(), errbuf.String())
+		if err := repo_module.RemoveTemporaryPath(tmpBasePath); err != nil {
+			log.Error("CreateTempRepo: RemoveTemporaryPath: %s", err)
+		}
+		return "", fmt.Errorf("Unable to set HEAD as base branch [tmpBasePath]: %w\n%s\n%s", err, outbuf.String(), errbuf.String())
 	}
+	outbuf.Reset()
+	errbuf.Reset()
 
 	if err := addCacheRepo(tmpBasePath, headRepoPath); err != nil {
-		log.Error("%-v Unable to add head repository to temporary repo [%s -> %s]: %v", pr, pr.HeadRepo.FullName(), tmpBasePath, err)
-		cancel()
-		return nil, nil, fmt.Errorf("Unable to add head base repository to temporary repo [%s -> tmpBasePath]: %w", pr.HeadRepo.FullName(), err)
+		log.Error("Unable to add head repository to temporary repo [%s -> %s]: %v", pr.HeadRepo.FullName(), tmpBasePath, err)
+		if err := repo_module.RemoveTemporaryPath(tmpBasePath); err != nil {
+			log.Error("CreateTempRepo: RemoveTemporaryPath: %s", err)
+		}
+		return "", fmt.Errorf("Unable to head base repository to temporary repo [%s -> tmpBasePath]: %w", pr.HeadRepo.FullName(), err)
 	}
 
 	if err := git.NewCommand(ctx, "remote", "add").AddDynamicArguments(remoteRepoName, headRepoPath).
-		Run(prCtx.RunOpts()); err != nil {
-		log.Error("%-v Unable to add head repository as head_repo [%s -> %s]: %v\n%s\n%s", pr, pr.HeadRepo.FullName(), tmpBasePath, err, prCtx.outbuf.String(), prCtx.errbuf.String())
-		cancel()
-		return nil, nil, fmt.Errorf("Unable to add head repository as head_repo [%s -> tmpBasePath]: %w\n%s\n%s", pr.HeadRepo.FullName(), err, prCtx.outbuf.String(), prCtx.errbuf.String())
+		Run(&git.RunOpts{
+			Dir:    tmpBasePath,
+			Stdout: &outbuf,
+			Stderr: &errbuf,
+		}); err != nil {
+		log.Error("Unable to add head repository as head_repo [%s -> %s]: %v\n%s\n%s", pr.HeadRepo.FullName(), tmpBasePath, err, outbuf.String(), errbuf.String())
+		if err := repo_module.RemoveTemporaryPath(tmpBasePath); err != nil {
+			log.Error("CreateTempRepo: RemoveTemporaryPath: %s", err)
+		}
+		return "", fmt.Errorf("Unable to add head repository as head_repo [%s -> tmpBasePath]: %w\n%s\n%s", pr.HeadRepo.FullName(), err, outbuf.String(), errbuf.String())
 	}
+	outbuf.Reset()
+	errbuf.Reset()
 
 	trackingBranch := "tracking"
 	// Fetch head branch
@@ -178,18 +178,24 @@ func createTemporaryRepoForPR(ctx context.Context, pr *issues_model.PullRequest)
 		headBranch = pr.GetGitRefName()
 	}
 	if err := git.NewCommand(ctx, "fetch").AddArguments(fetchArgs...).AddDynamicArguments(remoteRepoName, headBranch+":"+trackingBranch).
-		Run(prCtx.RunOpts()); err != nil {
-		cancel()
+		Run(&git.RunOpts{
+			Dir:    tmpBasePath,
+			Stdout: &outbuf,
+			Stderr: &errbuf,
+		}); err != nil {
+		if err := repo_module.RemoveTemporaryPath(tmpBasePath); err != nil {
+			log.Error("CreateTempRepo: RemoveTemporaryPath: %s", err)
+		}
 		if !git.IsBranchExist(ctx, pr.HeadRepo.RepoPath(), pr.HeadBranch) {
-			return nil, nil, models.ErrBranchDoesNotExist{
+			return "", models.ErrBranchDoesNotExist{
 				BranchName: pr.HeadBranch,
 			}
 		}
-		log.Error("%-v Unable to fetch head_repo head branch [%s:%s -> tracking in %s]: %v:\n%s\n%s", pr, pr.HeadRepo.FullName(), pr.HeadBranch, tmpBasePath, err, prCtx.outbuf.String(), prCtx.errbuf.String())
-		return nil, nil, fmt.Errorf("Unable to fetch head_repo head branch [%s:%s -> tracking in tmpBasePath]: %w\n%s\n%s", pr.HeadRepo.FullName(), headBranch, err, prCtx.outbuf.String(), prCtx.errbuf.String())
+		log.Error("Unable to fetch head_repo head branch [%s:%s -> tracking in %s]: %v:\n%s\n%s", pr.HeadRepo.FullName(), pr.HeadBranch, tmpBasePath, err, outbuf.String(), errbuf.String())
+		return "", fmt.Errorf("Unable to fetch head_repo head branch [%s:%s -> tracking in tmpBasePath]: %w\n%s\n%s", pr.HeadRepo.FullName(), headBranch, err, outbuf.String(), errbuf.String())
 	}
-	prCtx.outbuf.Reset()
-	prCtx.errbuf.Reset()
+	outbuf.Reset()
+	errbuf.Reset()
 
-	return prCtx, cancel, nil
+	return tmpBasePath, nil
 }

services/pull/update.go

@@ -16,67 +16,61 @@ import (
 	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/log"
+	repo_module "code.gitea.io/gitea/modules/repository"
 )
 
 // Update updates pull request with base branch.
-func Update(ctx context.Context, pr *issues_model.PullRequest, doer *user_model.User, message string, rebase bool) error {
-	if pr.Flow == issues_model.PullRequestFlowAGit {
-		// TODO: update of agit flow pull request's head branch is unsupported
-		return fmt.Errorf("update of agit flow pull request's head branch is unsupported")
+func Update(ctx context.Context, pull *issues_model.PullRequest, doer *user_model.User, message string, rebase bool) error {
+	var (
+		pr    *issues_model.PullRequest
+		style repo_model.MergeStyle
+	)
+
+	pullWorkingPool.CheckIn(fmt.Sprint(pull.ID))
+	defer pullWorkingPool.CheckOut(fmt.Sprint(pull.ID))
+
+	if rebase {
+		pr = pull
+		style = repo_model.MergeStyleRebaseUpdate
+	} else {
+		// use merge functions but switch repo's and branch's
+		pr = &issues_model.PullRequest{
+			HeadRepoID: pull.BaseRepoID,
+			BaseRepoID: pull.HeadRepoID,
+			HeadBranch: pull.BaseBranch,
+			BaseBranch: pull.HeadBranch,
+		}
+		style = repo_model.MergeStyleMerge
 	}
 
-	pullWorkingPool.CheckIn(fmt.Sprint(pr.ID))
-	defer pullWorkingPool.CheckOut(fmt.Sprint(pr.ID))
+	if pull.Flow == issues_model.PullRequestFlowAGit {
+		// TODO: Not support update agit flow pull request's head branch
+		return fmt.Errorf("Not support update agit flow pull request's head branch")
+	}
 
-	diffCount, err := GetDiverging(ctx, pr)
+	if err := pr.LoadHeadRepo(ctx); err != nil {
+		log.Error("LoadHeadRepo: %v", err)
+		return fmt.Errorf("LoadHeadRepo: %w", err)
+	} else if err = pr.LoadBaseRepo(ctx); err != nil {
+		log.Error("LoadBaseRepo: %v", err)
+		return fmt.Errorf("LoadBaseRepo: %w", err)
+	}
+
+	diffCount, err := GetDiverging(ctx, pull)
 	if err != nil {
 		return err
 	} else if diffCount.Behind == 0 {
-		return fmt.Errorf("HeadBranch of PR %d is up to date", pr.Index)
+		return fmt.Errorf("HeadBranch of PR %d is up to date", pull.Index)
 	}
 
-	if rebase {
-		defer func() {
-			go AddTestPullRequestTask(doer, pr.BaseRepo.ID, pr.BaseBranch, false, "", "")
-		}()
-
-		return updateHeadByRebaseOnToBase(ctx, pr, doer, message)
-	}
-
-	if err := pr.LoadBaseRepo(ctx); err != nil {
-		log.Error("unable to load BaseRepo for %-v during update-by-merge: %v", pr, err)
-		return fmt.Errorf("unable to load BaseRepo for PR[%d] during update-by-merge: %w", pr.ID, err)
-	}
-	if err := pr.LoadHeadRepo(ctx); err != nil {
-		log.Error("unable to load HeadRepo for PR %-v during update-by-merge: %v", pr, err)
-		return fmt.Errorf("unable to load HeadRepo for PR[%d] during update-by-merge: %w", pr.ID, err)
-	}
-	if pr.HeadRepo == nil {
-		// LoadHeadRepo will swallow ErrRepoNotExist so if pr.HeadRepo is still nil recreate the error
-		err := repo_model.ErrRepoNotExist{
-			ID: pr.HeadRepoID,
-		}
-		log.Error("unable to load HeadRepo for PR %-v during update-by-merge: %v", pr, err)
-		return fmt.Errorf("unable to load HeadRepo for PR[%d] during update-by-merge: %w", pr.ID, err)
-	}
-
-	// use merge functions but switch repos and branches
-	reversePR := &issues_model.PullRequest{
-		ID: pr.ID,
-
-		HeadRepoID: pr.BaseRepoID,
-		HeadRepo:   pr.BaseRepo,
-		HeadBranch: pr.BaseBranch,
-
-		BaseRepoID: pr.HeadRepoID,
-		BaseRepo:   pr.HeadRepo,
-		BaseBranch: pr.HeadBranch,
-	}
-
-	_, err = doMergeAndPush(ctx, reversePR, doer, repo_model.MergeStyleMerge, "", message)
+	_, err = rawMerge(ctx, pr, doer, style, "", message)
 
 	defer func() {
-		go AddTestPullRequestTask(doer, reversePR.HeadRepo.ID, reversePR.HeadBranch, false, "", "")
+		if rebase {
+			go AddTestPullRequestTask(doer, pr.BaseRepo.ID, pr.BaseBranch, false, "", "")
+			return
+		}
+		go AddTestPullRequestTask(doer, pr.HeadRepo.ID, pr.HeadBranch, false, "", "")
 	}()
 
 	return err
@@ -165,16 +159,27 @@ func IsUserAllowedToUpdate(ctx context.Context, pull *issues_model.PullRequest,
 
 // GetDiverging determines how many commits a PR is ahead or behind the PR base branch
 func GetDiverging(ctx context.Context, pr *issues_model.PullRequest) (*git.DivergeObject, error) {
-	log.Trace("GetDiverging[%-v]: compare commits", pr)
-	prCtx, cancel, err := createTemporaryRepoForPR(ctx, pr)
+	log.Trace("GetDiverging[%d]: compare commits", pr.ID)
+	if err := pr.LoadBaseRepo(ctx); err != nil {
+		return nil, err
+	}
+	if err := pr.LoadHeadRepo(ctx); err != nil {
+		return nil, err
+	}
+
+	tmpRepo, err := createTemporaryRepo(ctx, pr)
 	if err != nil {
 		if !models.IsErrBranchDoesNotExist(err) {
-			log.Error("CreateTemporaryRepoForPR %-v: %v", pr, err)
+			log.Error("CreateTemporaryRepo: %v", err)
 		}
 		return nil, err
 	}
-	defer cancel()
+	defer func() {
+		if err := repo_module.RemoveTemporaryPath(tmpRepo); err != nil {
+			log.Error("Merge: RemoveTemporaryPath: %s", err)
+		}
+	}()
 
-	diff, err := git.GetDivergingCommits(ctx, prCtx.tmpBasePath, baseBranch, trackingBranch)
+	diff, err := git.GetDivergingCommits(ctx, tmpRepo, "base", "tracking")
 	return &diff, err
 }

services/pull/update_rebase.go

@@ -1,107 +0,0 @@
-// Copyright 2023 The Gitea Authors. All rights reserved.
-// SPDX-License-Identifier: MIT
-
-package pull
-
-import (
-	"context"
-	"fmt"
-	"strings"
-
-	issues_model "code.gitea.io/gitea/models/issues"
-	repo_model "code.gitea.io/gitea/models/repo"
-	user_model "code.gitea.io/gitea/models/user"
-	"code.gitea.io/gitea/modules/git"
-	"code.gitea.io/gitea/modules/log"
-	repo_module "code.gitea.io/gitea/modules/repository"
-	"code.gitea.io/gitea/modules/setting"
-)
-
-// updateHeadByRebaseOnToBase handles updating a PR's head branch by rebasing it on the PR current base branch
-func updateHeadByRebaseOnToBase(ctx context.Context, pr *issues_model.PullRequest, doer *user_model.User, message string) error {
-	// "Clone" base repo and add the cache headers for the head repo and branch
-	mergeCtx, cancel, err := createTemporaryRepoForMerge(ctx, pr, doer, "")
-	if err != nil {
-		return err
-	}
-	defer cancel()
-
-	// Determine the old merge-base before the rebase - we use this for LFS push later on
-	oldMergeBase, _, _ := git.NewCommand(ctx, "merge-base").AddDashesAndList(baseBranch, trackingBranch).RunStdString(&git.RunOpts{Dir: mergeCtx.tmpBasePath})
-	oldMergeBase = strings.TrimSpace(oldMergeBase)
-
-	// Rebase the tracking branch on to the base as the staging branch
-	if err := rebaseTrackingOnToBase(mergeCtx, repo_model.MergeStyleRebaseUpdate); err != nil {
-		return err
-	}
-
-	if setting.LFS.StartServer {
-		// Now we need to ensure that the head repository contains any LFS objects between the new base and the old mergebase
-		// It's questionable about where this should go - either after or before the push
-		// I think in the interests of data safety - failures to push to the lfs should prevent
-		// the push as you can always re-rebase.
-		if err := LFSPush(ctx, mergeCtx.tmpBasePath, baseBranch, oldMergeBase, &issues_model.PullRequest{
-			HeadRepoID: pr.BaseRepoID,
-			BaseRepoID: pr.HeadRepoID,
-		}); err != nil {
-			log.Error("Unable to push lfs objects between %s and %s up to head branch in %-v: %v", baseBranch, oldMergeBase, pr, err)
-			return err
-		}
-	}
-
-	// Now determine who the pushing author should be
-	var headUser *user_model.User
-	if err := pr.HeadRepo.LoadOwner(ctx); err != nil {
-		if !user_model.IsErrUserNotExist(err) {
-			log.Error("Can't find user: %d for head repository in %-v - %v", pr.HeadRepo.OwnerID, pr, err)
-			return err
-		}
-		log.Error("Can't find user: %d for head repository in %-v - defaulting to doer: %-v - %v", pr.HeadRepo.OwnerID, pr, doer, err)
-		headUser = doer
-	} else {
-		headUser = pr.HeadRepo.Owner
-	}
-
-	pushCmd := git.NewCommand(ctx, "push", "-f", "head_repo").
-		AddDynamicArguments(stagingBranch + ":" + git.BranchPrefix + pr.HeadBranch)
-
-	// Push back to the head repository.
-	// TODO: this cause an api call to "/api/internal/hook/post-receive/...",
-	//       that prevents us from doint the whole merge in one db transaction
-	mergeCtx.outbuf.Reset()
-	mergeCtx.errbuf.Reset()
-
-	if err := pushCmd.Run(&git.RunOpts{
-		Env: repo_module.FullPushingEnvironment(
-			headUser,
-			doer,
-			pr.HeadRepo,
-			pr.HeadRepo.Name,
-			pr.ID,
-		),
-		Dir:    mergeCtx.tmpBasePath,
-		Stdout: mergeCtx.outbuf,
-		Stderr: mergeCtx.errbuf,
-	}); err != nil {
-		if strings.Contains(mergeCtx.errbuf.String(), "non-fast-forward") {
-			return &git.ErrPushOutOfDate{
-				StdOut: mergeCtx.outbuf.String(),
-				StdErr: mergeCtx.errbuf.String(),
-				Err:    err,
-			}
-		} else if strings.Contains(mergeCtx.errbuf.String(), "! [remote rejected]") {
-			err := &git.ErrPushRejected{
-				StdOut: mergeCtx.outbuf.String(),
-				StdErr: mergeCtx.errbuf.String(),
-				Err:    err,
-			}
-			err.GenerateMessage()
-			return err
-		}
-		return fmt.Errorf("git push: %s", mergeCtx.errbuf.String())
-	}
-	mergeCtx.outbuf.Reset()
-	mergeCtx.errbuf.Reset()
-
-	return nil
-}