improvements

models/issues/pull.go

@@ -256,6 +256,9 @@ func (pr *PullRequest) LoadHeadRepo(ctx context.Context) (err error) {
 			return fmt.Errorf("pr[%d].LoadHeadRepo[%d]: %w", pr.ID, pr.HeadRepoID, err)
 		}
 		pr.isHeadRepoLoaded = true
+		if pr.IsSameRepo() && pr.BaseRepo == nil {
+			pr.BaseRepo = pr.HeadRepo
+		}
 	}
 	return nil
 }
@@ -322,6 +325,9 @@ func (pr *PullRequest) LoadBaseRepo(ctx context.Context) (err error) {
 	if err != nil {
 		return fmt.Errorf("pr[%d].LoadBaseRepo[%d]: %w", pr.ID, pr.BaseRepoID, err)
 	}
+	if pr.IsSameRepo() && pr.HeadRepo == nil {
+		pr.HeadRepo = pr.BaseRepo
+	}
 	return nil
 }
 

models/migrations/v1_12/v136.go

@@ -6,7 +6,6 @@ package v1_12
 import (
 	"fmt"
 	"math"
-	"strings"
 	"time"
 
 	repo_model "code.gitea.io/gitea/models/repo"
@@ -18,19 +17,15 @@ import (
 	"xorm.io/xorm"
 )
 
-type Repository struct {
-	ID        int64 `xorm:"pk autoincr"`
-	OwnerID   int64 `xorm:"UNIQUE(s) index"`
-	OwnerName string
-	LowerName string `xorm:"UNIQUE(s) INDEX NOT NULL"`
-	Name      string `xorm:"INDEX NOT NULL"`
-}
-
-func (r *Repository) RelativePath() string {
-	return fmt.Sprintf("%s/%s.git", strings.ToLower(r.OwnerName), strings.ToLower(r.Name))
-}
-
 func AddCommitDivergenceToPulls(x *xorm.Engine) error {
+	type Repository struct {
+		ID        int64 `xorm:"pk autoincr"`
+		OwnerID   int64 `xorm:"UNIQUE(s) index"`
+		OwnerName string
+		LowerName string `xorm:"UNIQUE(s) INDEX NOT NULL"`
+		Name      string `xorm:"INDEX NOT NULL"`
+	}
+
 	type PullRequest struct {
 		ID      int64 `xorm:"pk autoincr"`
 		IssueID int64 `xorm:"INDEX"`

modules/gitrepo/fetch.go

@@ -0,0 +1,29 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package gitrepo
+
+import (
+	"context"
+	"fmt"
+
+	"code.gitea.io/gitea/modules/git/gitcmd"
+)
+
+// FetchRemoteBranch fetches a remote branch into a local branch
+func FetchRemoteBranch(ctx context.Context, repo Repository, localBranch string, remoteRepo Repository, remoteBranch string, args ...string) error {
+	_, _, err := gitcmd.NewCommand("fetch", "--no-tags", "--refmap=").
+		AddDynamicArguments(repoPath(remoteRepo)).
+		// + means force fetch
+		AddDynamicArguments(fmt.Sprintf("+refs/heads/%s:%s", remoteBranch, localBranch)).
+		RunStdString(ctx, &gitcmd.RunOpts{Dir: repoPath(repo)})
+	return err
+}
+
+func FetchRemoteCommit(ctx context.Context, repo, remoteRepo Repository, commitID string) error {
+	_, _, err := gitcmd.NewCommand("fetch", "--no-tags").
+		AddDynamicArguments(repoPath(remoteRepo)).
+		AddDynamicArguments(commitID).
+		RunStdString(ctx, &gitcmd.RunOpts{Dir: repoPath(repo)})
+	return err
+}

services/pull/pull.go

@@ -560,8 +560,7 @@ func UpdatePullsRefs(ctx context.Context, repo *repo_model.Repository, update *r
 func UpdatePullRequestAgitFlowHead(ctx context.Context, pr *issues_model.PullRequest, commitID string) error {
 	log.Trace("UpdateAgitPullRequestHead[%d]: update pull request head in base repo '%s'", pr.ID, pr.GetGitHeadRefName())
 
-	_, _, err := gitcmd.NewCommand("update-ref").AddDynamicArguments(pr.GetGitHeadRefName(), commitID).RunStdString(ctx, &gitcmd.RunOpts{Dir: pr.BaseRepo.RepoPath()})
-	return err
+	return gitrepo.UpdateRef(ctx, pr.BaseRepo, pr.GetGitHeadRefName(), commitID)
 }
 
 // UpdatePullRequestHeadRef updates the head reference of a pull request
@@ -572,21 +571,17 @@ func UpdatePullRequestGithubFlowHead(ctx context.Context, pr *issues_model.PullR
 		return err
 	}
 
-	if err := gitrepo.UpdateRef(ctx, pr.BaseRepo, pr.GetGitHeadRefName(), pr.HeadCommitID); err != nil {
-		log.Error("Unable to update ref in base repository for PR[%d] Error: %v", pr.ID, err)
+	if !pr.IsSameRepo() { // for cross repository pull request
+		if err := pr.LoadHeadRepo(ctx); err != nil {
+			return err
+		}
+
+		if err := gitrepo.FetchRemoteBranch(ctx, pr.BaseRepo, pr.GetGitHeadRefName(), pr.HeadRepo, pr.HeadBranch); err != nil {
+			return err
+		}
 	}
 
-	// for cross repository pull request
-	if err := pr.LoadHeadRepo(ctx); err != nil {
-		return err
-	}
-
-	_, _, err := gitcmd.NewCommand("fetch", "--no-tags", "--refmap=").
-		AddDynamicArguments(pr.HeadRepo.RepoPath()).
-		// + means force fetch
-		AddDynamicArguments(fmt.Sprintf("+refs/heads/%s:%s", pr.HeadBranch, pr.GetGitHeadRefName())).
-		RunStdString(ctx, &gitcmd.RunOpts{Dir: pr.BaseRepo.RepoPath()})
-	return err
+	return gitrepo.UpdateRef(ctx, pr.BaseRepo, pr.GetGitHeadRefName(), pr.HeadCommitID)
 }
 
 // retargetBranchPulls change target branch for all pull requests whose base branch is the branch

services/repository/branch.go

@@ -19,7 +19,6 @@ import (
 	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/cache"
 	"code.gitea.io/gitea/modules/git"
-	"code.gitea.io/gitea/modules/git/gitcmd"
 	"code.gitea.io/gitea/modules/gitrepo"
 	"code.gitea.io/gitea/modules/graceful"
 	"code.gitea.io/gitea/modules/json"
@@ -719,10 +718,8 @@ func GetBranchDivergingInfo(ctx reqctx.RequestContext, baseRepo *repo_model.Repo
 
 	// we need fetch the necessary commits from the head repo first if it's not the same repository
 	if baseRepo.ID != headRepo.ID {
-		if _, _, err := gitcmd.NewCommand("fetch", "--no-tags").
-			AddDynamicArguments(headRepo.RepoPath()).
-			AddDynamicArguments(headGitBranch.CommitID).
-			RunStdString(ctx, &gitcmd.RunOpts{Dir: baseRepo.RepoPath()}); err != nil {
+		// git default will gc the commit in 2 weeks, so it's safe to do the compare
+		if err := gitrepo.FetchRemoteCommit(ctx, baseRepo, headRepo, headGitBranch.CommitID); err != nil {
 			return nil, err
 		}
 	}