Merge 0bf39c72e7 into bc50431e8b

go.mod

@@ -109,7 +109,7 @@ require (
 	github.com/ulikunitz/xz v0.5.15
 	github.com/urfave/cli-docs/v3 v3.0.0-alpha6
 	github.com/urfave/cli/v3 v3.4.1
-	github.com/wneessen/go-mail v0.7.1
+	github.com/wneessen/go-mail v0.7.2
 	github.com/xeipuuv/gojsonschema v1.2.0
 	github.com/yohcop/openid-go v1.0.1
 	github.com/yuin/goldmark v1.7.13

go.sum

@@ -768,8 +768,8 @@ github.com/urfave/cli/v3 v3.4.1/go.mod h1:FJSKtM/9AiiTOJL4fJ6TbMUkxBXn7GO9guZqoZ
 github.com/valyala/fastjson v1.6.4 h1:uAUNq9Z6ymTgGhcm0UynUAB6tlbakBrz6CQFax3BXVQ=
 github.com/valyala/fastjson v1.6.4/go.mod h1:CLCAqky6SMuOcxStkYQvblddUtoRxhYMGLrsQns1aXY=
 github.com/willf/bitset v1.1.10/go.mod h1:RjeCKbqT1RxIR/KWY6phxZiaY1IyutSBfGjNPySAYV4=
-github.com/wneessen/go-mail v0.7.1 h1:rvy63sp14N06/kdGqCYwW8Na5gDCXjTQM1E7So4PuKk=
-github.com/wneessen/go-mail v0.7.1/go.mod h1:+TkW6QP3EVkgTEqHtVmnAE/1MRhmzb8Y9/W3pweuS+k=
+github.com/wneessen/go-mail v0.7.2 h1:xxPnhZ6IZLSgxShebmZ6DPKh1b6OJcoHfzy7UjOkzS8=
+github.com/wneessen/go-mail v0.7.2/go.mod h1:+TkW6QP3EVkgTEqHtVmnAE/1MRhmzb8Y9/W3pweuS+k=
 github.com/x448/float16 v0.8.4 h1:qLwI1I70+NjRFUR3zs1JPUCgaCXSh3SW62uAKT1mSBM=
 github.com/x448/float16 v0.8.4/go.mod h1:14CWIYCyZA/cWjXOioeEpHeN/83MdbZDRQHoFcYsOfg=
 github.com/xanzy/ssh-agent v0.3.3 h1:+/15pJfg/RsTxqYcX6fHqOXZwwMP+2VyYWJeWM2qQFM=

modules/git/commit_test.go

@@ -4,7 +4,6 @@
 package git
 
 import (
-	"os"
 	"path/filepath"
 	"strings"
 	"testing"
@@ -339,18 +338,3 @@ func TestGetCommitFileStatusMerges(t *testing.T) {
 	assert.Equal(t, expected.Removed, commitFileStatus.Removed)
 	assert.Equal(t, expected.Modified, commitFileStatus.Modified)
 }
-
-func Test_GetCommitBranchStart(t *testing.T) {
-	bareRepo1Path := filepath.Join(testReposDir, "repo1_bare")
-	repo, err := OpenRepository(t.Context(), bareRepo1Path)
-	assert.NoError(t, err)
-	defer repo.Close()
-	commit, err := repo.GetBranchCommit("branch1")
-	assert.NoError(t, err)
-	assert.Equal(t, "2839944139e0de9737a044f78b0e4b40d989a9e3", commit.ID.String())
-
-	startCommitID, err := repo.GetCommitBranchStart(os.Environ(), "branch1", commit.ID.String())
-	assert.NoError(t, err)
-	assert.NotEmpty(t, startCommitID)
-	assert.Equal(t, "95bb4d39648ee7e325106df01a621c530863a653", startCommitID)
-}

modules/git/diff.go

@@ -7,6 +7,7 @@ import (
 	"bufio"
 	"bytes"
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"os"
@@ -288,20 +289,18 @@ func CutDiffAroundLine(originalDiff io.Reader, line int64, old bool, numbersOfLi
 }
 
 // GetAffectedFiles returns the affected files between two commits
-func GetAffectedFiles(repo *Repository, branchName, oldCommitID, newCommitID string, env []string) ([]string, error) {
-	if oldCommitID == emptySha1ObjectID.String() || oldCommitID == emptySha256ObjectID.String() {
-		startCommitID, err := repo.GetCommitBranchStart(env, branchName, newCommitID)
-		if err != nil {
-			return nil, err
-		}
-		if startCommitID == "" {
-			return nil, fmt.Errorf("cannot find the start commit of %s", newCommitID)
-		}
-		oldCommitID = startCommitID
+func GetAffectedFiles(ctx context.Context, repoPath, oldCommitID, newCommitID string, env []string) ([]string, error) {
+	if oldCommitID == emptySha1ObjectID.String() {
+		oldCommitID = emptySha1ObjectID.Type().EmptyTree().String()
+	} else if oldCommitID == emptySha256ObjectID.String() {
+		oldCommitID = emptySha256ObjectID.Type().EmptyTree().String()
+	} else if oldCommitID == "" {
+		return nil, errors.New("oldCommitID is empty")
 	}
+
 	stdoutReader, stdoutWriter, err := os.Pipe()
 	if err != nil {
-		log.Error("Unable to create os.Pipe for %s", repo.Path)
+		log.Error("Unable to create os.Pipe for %s", repoPath)
 		return nil, err
 	}
 	defer func() {
@@ -314,7 +313,7 @@ func GetAffectedFiles(repo *Repository, branchName, oldCommitID, newCommitID str
 	// Run `git diff --name-only` to get the names of the changed files
 	err = gitcmd.NewCommand("diff", "--name-only").AddDynamicArguments(oldCommitID, newCommitID).
 		WithEnv(env).
-		WithDir(repo.Path).
+		WithDir(repoPath).
 		WithStdout(stdoutWriter).
 		WithPipelineFunc(func(ctx context.Context, cancel context.CancelFunc) error {
 			// Close the writer end of the pipe to begin processing
@@ -334,9 +333,9 @@ func GetAffectedFiles(repo *Repository, branchName, oldCommitID, newCommitID str
 			}
 			return scanner.Err()
 		}).
-		Run(repo.Ctx)
+		Run(ctx)
 	if err != nil {
-		log.Error("Unable to get affected files for commits from %s to %s in %s: %v", oldCommitID, newCommitID, repo.Path, err)
+		log.Error("Unable to get affected files for commits from %s to %s in %s: %v", oldCommitID, newCommitID, repoPath, err)
 	}
 
 	return affectedFiles, err

modules/git/git.go

@@ -31,6 +31,7 @@ type Features struct {
 	SupportHashSha256      bool           // >= 2.42, SHA-256 repositories no longer an ‘experimental curiosity’
 	SupportedObjectFormats []ObjectFormat // sha1, sha256
 	SupportCheckAttrOnBare bool           // >= 2.40
+	SupportGitMergeTree    bool           // >= 2.38
 }
 
 var defaultFeatures *Features
@@ -75,6 +76,7 @@ func loadGitVersionFeatures() (*Features, error) {
 		features.SupportedObjectFormats = append(features.SupportedObjectFormats, Sha256ObjectFormat)
 	}
 	features.SupportCheckAttrOnBare = features.CheckVersionAtLeast("2.40")
+	features.SupportGitMergeTree = features.CheckVersionAtLeast("2.38")
 	return features, nil
 }
 

modules/git/gitcmd/command.go

@@ -456,6 +456,17 @@ func IsErrorExitCode(err error, code int) bool {
 	return false
 }
 
+func ExitCode(err error) (int, bool) {
+	if err == nil {
+		return 0, true
+	}
+	var exitError *exec.ExitError
+	if errors.As(err, &exitError) {
+		return exitError.ExitCode(), true
+	}
+	return 0, false
+}
+
 // RunStdString runs the command and returns stdout/stderr as string. and store stderr to returned error (err combined with stderr).
 func (c *Command) RunStdString(ctx context.Context) (stdout, stderr string, runErr RunStdError) {
 	stdoutBytes, stderrBytes, runErr := c.WithParentCallerInfo().runStdBytes(ctx)

modules/git/repo_commit.go

@@ -580,34 +580,3 @@ func (repo *Repository) AddLastCommitCache(cacheKey, fullName, sha string) error
 	}
 	return nil
 }
-
-// GetCommitBranchStart returns the commit where the branch diverged
-func (repo *Repository) GetCommitBranchStart(env []string, branch, endCommitID string) (string, error) {
-	cmd := gitcmd.NewCommand("log", prettyLogFormat)
-	cmd.AddDynamicArguments(endCommitID)
-
-	stdout, _, runErr := cmd.WithDir(repo.Path).
-		WithEnv(env).
-		RunStdBytes(repo.Ctx)
-	if runErr != nil {
-		return "", runErr
-	}
-
-	parts := bytes.SplitSeq(bytes.TrimSpace(stdout), []byte{'\n'})
-
-	// check the commits one by one until we find a commit contained by another branch
-	// and we think this commit is the divergence point
-	for commitID := range parts {
-		branches, err := repo.getBranches(env, string(commitID), 2)
-		if err != nil {
-			return "", err
-		}
-		for _, b := range branches {
-			if b != branch {
-				return string(commitID), nil
-			}
-		}
-	}
-
-	return "", nil
-}

modules/gitrepo/fetch.go

@@ -0,0 +1,16 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package gitrepo
+
+import (
+	"context"
+
+	"code.gitea.io/gitea/modules/git/gitcmd"
+)
+
+func FetchRemoteCommit(ctx context.Context, repo, remoteRepo Repository, commitID string) error {
+	return RunCmd(ctx, repo, gitcmd.NewCommand("fetch", "--no-tags").
+		AddDynamicArguments(repoPath(remoteRepo)).
+		AddDynamicArguments(commitID))
+}

modules/gitrepo/merge.go

@@ -0,0 +1,75 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package gitrepo
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"fmt"
+	"strings"
+
+	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/git/gitcmd"
+)
+
+func MergeBase(ctx context.Context, repo Repository, commit1, commit2 string) (string, error) {
+	mergeBase, err := RunCmdString(ctx, repo, gitcmd.NewCommand("merge-base", "--").
+		AddDynamicArguments(commit1, commit2))
+	if err != nil {
+		return "", fmt.Errorf("get merge-base of %s and %s failed: %w", commit1, commit2, err)
+	}
+	return strings.TrimSpace(mergeBase), nil
+}
+
+// parseMergeTreeOutput parses the output of git merge-tree --write-tree -z --name-only --no-messages
+// For a successful merge, the output is a simply one line <OID of toplevel tree>NUL
+// Whereas for a conflicted merge, the output is:
+// <OID of toplevel tree>NUL
+// <Conflicted file name 1>NUL
+// <Conflicted file name 2>NUL
+// ...
+// ref: https://git-scm.com/docs/git-merge-tree/2.38.0#OUTPUT
+func parseMergeTreeOutput(output string) (string, []string, error) {
+	fields := strings.Split(strings.TrimSuffix(output, "\x00"), "\x00")
+	switch len(fields) {
+	case 0:
+		return "", nil, errors.New("unexpected empty output")
+	case 1:
+		return strings.TrimSpace(fields[0]), nil, nil
+	default:
+		return strings.TrimSpace(fields[0]), fields[1:], nil
+	}
+}
+
+// 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) (string, bool, []string, error) {
+	cmd := gitcmd.NewCommand("merge-tree", "--write-tree", "-z", "--name-only", "--no-messages")
+	if git.DefaultFeatures().CheckVersionAtLeast("2.40") && mergeBase != "" {
+		cmd.AddOptionFormat("--merge-base=%s", mergeBase)
+	}
+
+	stdout := &bytes.Buffer{}
+	gitErr := RunCmd(ctx, repo, cmd.AddDynamicArguments(baseRef, headRef).WithStdout(stdout))
+	exitCode, ok := gitcmd.ExitCode(gitErr)
+	if !ok {
+		return "", false, nil, fmt.Errorf("run merge-tree failed: %w", gitErr)
+	}
+
+	switch exitCode {
+	case 0, 1:
+		treeID, conflictedFiles, err := parseMergeTreeOutput(stdout.String())
+		if err != nil {
+			return "", false, nil, fmt.Errorf("parse merge-tree output failed: %w", err)
+		}
+		// 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
+		return treeID, exitCode == 1, conflictedFiles, nil
+	default:
+		return "", false, nil, fmt.Errorf("run merge-tree exit abnormally: %w", gitErr)
+	}
+}

modules/gitrepo/merge_test.go

@@ -0,0 +1,26 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package gitrepo
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_parseMergeTreeOutput(t *testing.T) {
+	conflictedOutput := "837480c2773160381cbe6bcce90f7732789b5856\x00options/locale/locale_en-US.ini\x00services/webhook/webhook_test.go\x00"
+	treeID, conflictedFiles, err := parseMergeTreeOutput(conflictedOutput)
+	assert.NoError(t, err)
+	assert.Equal(t, "837480c2773160381cbe6bcce90f7732789b5856", treeID)
+	assert.Len(t, conflictedFiles, 2)
+	assert.Equal(t, "options/locale/locale_en-US.ini", conflictedFiles[0])
+	assert.Equal(t, "services/webhook/webhook_test.go", conflictedFiles[1])
+
+	nonConflictedOutput := "837480c2773160381cbe6bcce90f7732789b5856\x00"
+	treeID, conflictedFiles, err = parseMergeTreeOutput(nonConflictedOutput)
+	assert.NoError(t, err)
+	assert.Equal(t, "837480c2773160381cbe6bcce90f7732789b5856", treeID)
+	assert.Empty(t, conflictedFiles)
+}

options/locale/locale_cs-CZ.ini

@@ -3586,6 +3586,7 @@ variables.update.success=Proměnná byla upravena.
 logs.always_auto_scroll=Vždy automaticky posouvat logy
 logs.always_expand_running=Vždy rozšířit běžící logy
 
+
 [projects]
 deleted.display_name=Odstraněný projekt
 type-1.display_name=Samostatný projekt

options/locale/locale_de-DE.ini

@@ -3645,6 +3645,7 @@ variables.update.success=Die Variable wurde bearbeitet.
 logs.always_auto_scroll=Autoscroll für Logs immer aktivieren
 logs.always_expand_running=Laufende Logs immer erweitern
 
+
 [projects]
 deleted.display_name=Gelöschtes Projekt
 type-1.display_name=Individuelles Projekt

options/locale/locale_el-GR.ini

@@ -3280,6 +3280,7 @@ variables.update.failed=Αποτυχία επεξεργασίας μεταβλη
 variables.update.success=Η μεταβλητή έχει τροποποιηθεί.
 
 
+
 [projects]
 type-1.display_name=Ατομικό Έργο
 type-2.display_name=Έργο Αποθετηρίου

options/locale/locale_es-ES.ini

@@ -3257,6 +3257,7 @@ variables.update.failed=Error al editar la variable.
 variables.update.success=La variable ha sido editada.
 
 
+
 [projects]
 type-1.display_name=Proyecto individual
 type-2.display_name=Proyecto repositorio

options/locale/locale_fa-IR.ini

@@ -2446,6 +2446,7 @@ runs.commit=کامیت
 
 
 
+
 [projects]
 
 [git.filemode]

options/locale/locale_fi-FI.ini

@@ -1693,6 +1693,7 @@ runs.commit=Commit
 
 
 
+
 [projects]
 
 [git.filemode]

options/locale/locale_fr-FR.ini

@@ -3906,6 +3906,7 @@ variables.update.success=La variable a bien été modifiée.
 logs.always_auto_scroll=Toujours faire défiler les journaux automatiquement
 logs.always_expand_running=Toujours développer les journaux en cours
 
+
 [projects]
 deleted.display_name=Projet supprimé
 type-1.display_name=Projet personnel

options/locale/locale_ga-IE.ini

@@ -3914,6 +3914,7 @@ variables.update.success=Tá an t-athróg curtha in eagar.
 logs.always_auto_scroll=Logchomhaid scrollaithe uathoibríoch i gcónaí
 logs.always_expand_running=Leathnaigh logs reatha i gcónaí
 
+
 [projects]
 deleted.display_name=Tionscadal scriosta
 type-1.display_name=Tionscadal Aonair

options/locale/locale_hu-HU.ini

@@ -1605,6 +1605,7 @@ runs.commit=Commit
 
 
 
+
 [projects]
 
 [git.filemode]

options/locale/locale_id-ID.ini

@@ -1428,6 +1428,7 @@ variables.update.failed=Gagal mengedit variabel.
 variables.update.success=Variabel telah diedit.
 
 
+
 [projects]
 type-1.display_name=Proyek Individu
 type-2.display_name=Proyek Repositori

options/locale/locale_is-IS.ini

@@ -1334,6 +1334,7 @@ runs.commit=Framlag
 
 
 
+
 [projects]
 
 [git.filemode]

options/locale/locale_it-IT.ini

@@ -2706,6 +2706,7 @@ runs.commit=Commit
 
 
 
+
 [projects]
 
 [git.filemode]

options/locale/locale_ja-JP.ini

@@ -3910,6 +3910,7 @@ variables.update.success=変数を更新しました。
 logs.always_auto_scroll=常にログを自動スクロール
 logs.always_expand_running=常に実行中のログを展開
 
+
 [projects]
 deleted.display_name=削除されたプロジェクト
 type-1.display_name=個人プロジェクト

options/locale/locale_ko-KR.ini

@@ -1554,6 +1554,7 @@ runs.commit=커밋
 
 
 
+
 [projects]
 
 [git.filemode]

options/locale/locale_lv-LV.ini

@@ -3282,6 +3282,7 @@ variables.update.failed=Neizdevās labot mainīgo.
 variables.update.success=Mainīgais tika labots.
 
 
+
 [projects]
 type-1.display_name=Individuālais projekts
 type-2.display_name=Repozitorija projekts

options/locale/locale_nl-NL.ini

@@ -2458,6 +2458,7 @@ runs.commit=Commit
 
 
 
+
 [projects]
 
 [git.filemode]

options/locale/locale_pl-PL.ini

@@ -2347,6 +2347,7 @@ runs.commit=Commit
 
 
 
+
 [projects]
 
 [git.filemode]

options/locale/locale_pt-BR.ini

@@ -3615,6 +3615,7 @@ variables.update.failed=Falha ao editar a variável.
 variables.update.success=A variável foi editada.
 
 
+
 [projects]
 deleted.display_name=Excluir Projeto
 type-1.display_name=Projeto Individual

options/locale/locale_pt-PT.ini

@@ -3914,6 +3914,7 @@ variables.update.success=A variável foi editada.
 logs.always_auto_scroll=Rolar registos de forma automática e permanente
 logs.always_expand_running=Expandir sempre os registos que vão rolando
 
+
 [projects]
 deleted.display_name=Planeamento eliminado
 type-1.display_name=Planeamento individual

options/locale/locale_ru-RU.ini

@@ -3225,6 +3225,7 @@ variables.update.failed=Не удалось изменить переменну
 variables.update.success=Переменная изменена.
 
 
+
 [projects]
 type-1.display_name=Индивидуальный проект
 type-2.display_name=Проект репозитория

options/locale/locale_si-LK.ini

@@ -2391,6 +2391,7 @@ runs.commit=කැප
 
 
 
+
 [projects]
 
 [git.filemode]

options/locale/locale_sk-SK.ini

@@ -1292,6 +1292,7 @@ runners.labels=Štítky
 
 
 
+
 [projects]
 
 [git.filemode]

options/locale/locale_sv-SE.ini

@@ -1968,6 +1968,7 @@ runs.commit=Commit
 
 
 
+
 [projects]
 
 [git.filemode]

options/locale/locale_tr-TR.ini

@@ -3907,6 +3907,7 @@ variables.update.success=Değişken düzenlendi.
 logs.always_auto_scroll=Günlükleri her zaman otomatik kaydır
 logs.always_expand_running=Çalıştırma günlüklerini her zaman genişlet
 
+
 [projects]
 deleted.display_name=Silinmiş Proje
 type-1.display_name=Kişisel Proje

options/locale/locale_uk-UA.ini

@@ -3428,6 +3428,7 @@ variables.update.success=Змінну відредаговано.
 logs.always_auto_scroll=Завжди автоматично прокручувати журнали
 logs.always_expand_running=Завжди розгортати поточні журнали
 
+
 [projects]
 deleted.display_name=Видалений проєкт
 type-1.display_name=Індивідуальний проєкт

options/locale/locale_zh-CN.ini

@@ -3911,6 +3911,7 @@ variables.update.success=变量已编辑。
 logs.always_auto_scroll=总是自动滚动日志
 logs.always_expand_running=总是展开运行日志
 
+
 [projects]
 deleted.display_name=已删除项目
 type-1.display_name=个人项目

options/locale/locale_zh-HK.ini

@@ -980,6 +980,7 @@ runners.task_list.repository=儲存庫
 
 
 
+
 [projects]
 
 [git.filemode]

options/locale/locale_zh-TW.ini

@@ -3554,6 +3554,7 @@ variables.update.failed=編輯變數失敗。
 variables.update.success=已編輯變數。
 
 
+
 [projects]
 deleted.display_name=已刪除的專案
 type-1.display_name=個人專案

routers/private/hook_pre_receive.go

@@ -244,7 +244,7 @@ func preReceiveBranch(ctx *preReceiveContext, oldCommitID, newCommitID string, r
 
 	globs := protectBranch.GetProtectedFilePatterns()
 	if len(globs) > 0 {
-		_, err := pull_service.CheckFileProtection(gitRepo, branchName, oldCommitID, newCommitID, globs, 1, ctx.env)
+		_, err := pull_service.CheckFileProtection(ctx, repo.RepoPath(), oldCommitID, newCommitID, globs, 1, ctx.env)
 		if err != nil {
 			if !pull_service.IsErrFilePathProtected(err) {
 				log.Error("Unable to check file protection for commits from %s to %s in %-v: %v", oldCommitID, newCommitID, repo, err)
@@ -302,7 +302,7 @@ func preReceiveBranch(ctx *preReceiveContext, oldCommitID, newCommitID string, r
 			// Allow commits that only touch unprotected files
 			globs := protectBranch.GetUnprotectedFilePatterns()
 			if len(globs) > 0 {
-				unprotectedFilesOnly, err := pull_service.CheckUnprotectedFiles(gitRepo, branchName, oldCommitID, newCommitID, globs, ctx.env)
+				unprotectedFilesOnly, err := pull_service.CheckUnprotectedFiles(ctx, repo, oldCommitID, newCommitID, globs, ctx.env)
 				if err != nil {
 					log.Error("Unable to check file protection for commits from %s to %s in %-v: %v", oldCommitID, newCommitID, repo, err)
 					ctx.JSON(http.StatusInternalServerError, private.Response{

services/pull/check.go

@@ -437,7 +437,7 @@ func checkPullRequestMergeable(id int64) {
 		return
 	}
 
-	if err := testPullRequestBranchMergeable(pr); err != nil {
+	if err := checkPullRequestMergeableAndUpdateStatus(ctx, pr); err != nil {
 		log.Error("testPullRequestTmpRepoBranchMergeable[%-v]: %v", pr, err)
 		pr.Status = issues_model.PullRequestStatusError
 		if err := pr.UpdateCols(ctx, "status"); err != nil {

services/pull/conflicts.go

@@ -0,0 +1,155 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package pull
+
+import (
+	"context"
+	"errors"
+	"fmt"
+
+	issues_model "code.gitea.io/gitea/models/issues"
+	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/git/gitcmd"
+	"code.gitea.io/gitea/modules/gitrepo"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/util"
+)
+
+// checkPullRequestMergeableAndUpdateStatus checks whether a pull request is mergeable and updates its status accordingly.
+// It uses 'git merge-tree' if supported by the Git version, otherwise it falls back to using a temporary repository.
+// This function updates the pr.Status, pr.MergeBase and pr.ConflictedFiles fields as necessary.
+// The pull request parameter may not be created yet in the database, so do not assume it has an ID.
+func checkPullRequestMergeableAndUpdateStatus(ctx context.Context, pr *issues_model.PullRequest) error {
+	if git.DefaultFeatures().SupportGitMergeTree {
+		return checkPullRequestMergeableAndUpdateStatusMergeTree(ctx, pr)
+	}
+
+	return checkPullRequestMergeableAndUpdateStatusTmpRepo(ctx, pr)
+}
+
+// checkConflictsMergeTree uses git merge-tree to check for conflicts and if none are found checks if the patch is empty
+// return true if there is conflicts otherwise return false
+// pr.Status and pr.ConflictedFiles will be updated as necessary
+func checkConflictsMergeTree(ctx context.Context, pr *issues_model.PullRequest, baseCommitID string) (bool, error) {
+	treeHash, conflict, conflictFiles, err := gitrepo.MergeTree(ctx, pr.BaseRepo, baseCommitID, pr.HeadCommitID, pr.MergeBase)
+	if err != nil {
+		return false, fmt.Errorf("MergeTree: %w", err)
+	}
+	if conflict {
+		pr.Status = issues_model.PullRequestStatusConflict
+		pr.ConflictedFiles = util.Iif(len(conflictFiles) > 0, conflictFiles, []string{"(no files listed)"})
+
+		log.Trace("Found %d files conflicted: %v", len(pr.ConflictedFiles), pr.ConflictedFiles)
+		return true, nil
+	}
+
+	// Detecting whether the pull request has difference via git diff-tree
+	// it will return exit code 0 if there's no diff and exit code 1 if there's a diff.
+	gitErr := gitrepo.RunCmd(ctx, pr.BaseRepo, gitcmd.NewCommand("diff-tree", "-r", "--quiet").
+		AddDynamicArguments(treeHash, pr.MergeBase))
+	exitCode, ok := gitcmd.ExitCode(gitErr)
+	if !ok {
+		return false, fmt.Errorf("run diff-tree failed: %w", gitErr)
+	}
+
+	switch exitCode {
+	case 0:
+		log.Debug("PullRequest[%d]: Patch is empty - ignoring", pr.ID)
+		pr.Status = issues_model.PullRequestStatusEmpty
+	case 1:
+		pr.Status = issues_model.PullRequestStatusMergeable
+	default:
+		return false, fmt.Errorf("run diff-tree exit abnormally: %w", gitErr)
+	}
+	return false, nil
+}
+
+func checkPullRequestMergeableAndUpdateStatusMergeTree(ctx context.Context, pr *issues_model.PullRequest) error {
+	// 1. Get head commit
+	if err := pr.LoadHeadRepo(ctx); err != nil {
+		return err
+	}
+	headGitRepo, err := gitrepo.OpenRepository(ctx, pr.HeadRepo)
+	if err != nil {
+		return fmt.Errorf("OpenRepository: %w", err)
+	}
+	defer headGitRepo.Close()
+
+	// 2. Get base commit id
+	var baseGitRepo *git.Repository
+	if pr.IsSameRepo() {
+		baseGitRepo = headGitRepo
+	} else {
+		baseGitRepo, err = gitrepo.OpenRepository(ctx, pr.BaseRepo)
+		if err != nil {
+			return fmt.Errorf("OpenRepository: %w", err)
+		}
+		defer baseGitRepo.Close()
+	}
+
+	// 3. Get head commit id
+	if pr.Flow == issues_model.PullRequestFlowGithub {
+		pr.HeadCommitID, err = headGitRepo.GetRefCommitID(git.BranchPrefix + pr.HeadBranch)
+		if err != nil {
+			return fmt.Errorf("GetBranchCommitID: can't find commit ID for head: %w", err)
+		}
+	} else {
+		if pr.ID > 0 {
+			pr.HeadCommitID, err = baseGitRepo.GetRefCommitID(pr.GetGitHeadRefName())
+			if err != nil {
+				return fmt.Errorf("GetRefCommitID: can't find commit ID for head: %w", err)
+			}
+		} else if pr.HeadCommitID == "" { // for new pull request with agit, the head commit id must be provided
+			return errors.New("head commit ID is empty for pull request Agit flow")
+		}
+	}
+
+	// 4. fetch head commit id into the current repository
+	// it will be checked in 2 weeks by default from git if the pull request created failure.
+	if !pr.IsSameRepo() {
+		if err := gitrepo.FetchRemoteCommit(ctx, pr.BaseRepo, pr.HeadRepo, pr.HeadCommitID); err != nil {
+			return fmt.Errorf("FetchRemoteCommit: %w", err)
+		}
+	}
+
+	// 5. update merge base
+	baseCommitID, err := baseGitRepo.GetRefCommitID(git.BranchPrefix + pr.BaseBranch)
+	if err != nil {
+		return fmt.Errorf("GetBranchCommitID: can't find commit ID for base: %w", err)
+	}
+
+	pr.MergeBase, err = gitrepo.MergeBase(ctx, pr.BaseRepo, baseCommitID, pr.HeadCommitID)
+	if err != nil {
+		log.Error("GetMergeBase: %v and can't find commit ID for base: %v", err, baseCommitID)
+		pr.Status = issues_model.PullRequestStatusEmpty // if there is no merge base, then it's empty but we still need to allow the pull request created
+		return nil
+	}
+
+	// 6. if base == head, then it's an ancestor
+	if pr.HeadCommitID == pr.MergeBase {
+		pr.Status = issues_model.PullRequestStatusAncestor
+		return nil
+	}
+
+	// 7. Check for conflicts
+	conflicted, err := checkConflictsMergeTree(ctx, pr, baseCommitID)
+	if err != nil {
+		log.Error("checkConflictsMergeTree: %v", err)
+		pr.Status = issues_model.PullRequestStatusEmpty // if there is no merge base, then it's empty but we still need to allow the pull request created
+	}
+	if conflicted || pr.Status == issues_model.PullRequestStatusEmpty {
+		return nil
+	}
+
+	// 7. Check for protected files changes
+	if err = checkPullFilesProtection(ctx, pr, pr.BaseRepo.RepoPath()); err != nil {
+		return fmt.Errorf("pr.CheckPullFilesProtection(): %v", err)
+	}
+	if len(pr.ChangedProtectedFiles) > 0 {
+		log.Trace("Found %d protected files changed", len(pr.ChangedProtectedFiles))
+	}
+
+	pr.Status = issues_model.PullRequestStatusMergeable
+	return nil
+}

services/pull/patch.go

@@ -1,5 +1,4 @@
-// Copyright 2019 The Gitea Authors.
-// All rights reserved.
+// Copyright 2019 The Gitea Authors. All rights reserved.
 // SPDX-License-Identifier: MIT
 
 package pull
@@ -15,15 +14,14 @@ import (
 
 	git_model "code.gitea.io/gitea/models/git"
 	issues_model "code.gitea.io/gitea/models/issues"
+	repo_model "code.gitea.io/gitea/models/repo"
 	"code.gitea.io/gitea/models/unit"
 	"code.gitea.io/gitea/modules/container"
 	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/git/gitcmd"
 	"code.gitea.io/gitea/modules/gitrepo"
 	"code.gitea.io/gitea/modules/glob"
-	"code.gitea.io/gitea/modules/graceful"
 	"code.gitea.io/gitea/modules/log"
-	"code.gitea.io/gitea/modules/process"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/util"
 )
@@ -67,10 +65,7 @@ var patchErrorSuffices = []string{
 	": does not exist in index",
 }
 
-func testPullRequestBranchMergeable(pr *issues_model.PullRequest) error {
-	ctx, _, finished := process.GetManager().AddContext(graceful.GetManager().HammerContext(), fmt.Sprintf("testPullRequestBranchMergeable: %s", pr))
-	defer finished()
-
+func checkPullRequestMergeableAndUpdateStatusTmpRepo(ctx context.Context, pr *issues_model.PullRequest) error {
 	prCtx, cancel, err := createTemporaryRepoForPR(ctx, pr)
 	if err != nil {
 		if !git_model.IsErrBranchNotExist(err) {
@@ -80,10 +75,6 @@ func testPullRequestBranchMergeable(pr *issues_model.PullRequest) error {
 	}
 	defer cancel()
 
-	return testPullRequestTmpRepoBranchMergeable(ctx, prCtx, pr)
-}
-
-func testPullRequestTmpRepoBranchMergeable(ctx context.Context, prCtx *prTmpRepoContext, pr *issues_model.PullRequest) error {
 	gitRepo, err := git.OpenRepository(ctx, prCtx.tmpBasePath)
 	if err != nil {
 		return fmt.Errorf("OpenRepository: %w", err)
@@ -115,7 +106,7 @@ func testPullRequestTmpRepoBranchMergeable(ctx context.Context, prCtx *prTmpRepo
 	}
 
 	// 3. Check for protected files changes
-	if err = checkPullFilesProtection(ctx, pr, gitRepo); err != nil {
+	if err = checkPullFilesProtection(ctx, pr, prCtx.tmpBasePath); err != nil {
 		return fmt.Errorf("pr.CheckPullFilesProtection(): %v", err)
 	}
 
@@ -530,11 +521,11 @@ func (err ErrFilePathProtected) Unwrap() error {
 }
 
 // CheckFileProtection check file Protection
-func CheckFileProtection(repo *git.Repository, branchName, oldCommitID, newCommitID string, patterns []glob.Glob, limit int, env []string) ([]string, error) {
+func CheckFileProtection(ctx context.Context, repoPath, oldCommitID, newCommitID string, patterns []glob.Glob, limit int, env []string) ([]string, error) {
 	if len(patterns) == 0 {
 		return nil, nil
 	}
-	affectedFiles, err := git.GetAffectedFiles(repo, branchName, oldCommitID, newCommitID, env)
+	affectedFiles, err := git.GetAffectedFiles(ctx, repoPath, oldCommitID, newCommitID, env)
 	if err != nil {
 		return nil, err
 	}
@@ -560,11 +551,11 @@ func CheckFileProtection(repo *git.Repository, branchName, oldCommitID, newCommi
 }
 
 // CheckUnprotectedFiles check if the commit only touches unprotected files
-func CheckUnprotectedFiles(repo *git.Repository, branchName, oldCommitID, newCommitID string, patterns []glob.Glob, env []string) (bool, error) {
+func CheckUnprotectedFiles(ctx context.Context, repo *repo_model.Repository, oldCommitID, newCommitID string, patterns []glob.Glob, env []string) (bool, error) {
 	if len(patterns) == 0 {
 		return false, nil
 	}
-	affectedFiles, err := git.GetAffectedFiles(repo, branchName, oldCommitID, newCommitID, env)
+	affectedFiles, err := git.GetAffectedFiles(ctx, repo.RepoPath(), oldCommitID, newCommitID, env)
 	if err != nil {
 		return false, err
 	}
@@ -585,7 +576,8 @@ func CheckUnprotectedFiles(repo *git.Repository, branchName, oldCommitID, newCom
 }
 
 // checkPullFilesProtection check if pr changed protected files and save results
-func checkPullFilesProtection(ctx context.Context, pr *issues_model.PullRequest, gitRepo *git.Repository) error {
+// repoPath might be a temporary path so that we need to pass it in
+func checkPullFilesProtection(ctx context.Context, pr *issues_model.PullRequest, repoPath string) error {
 	if pr.Status == issues_model.PullRequestStatusEmpty {
 		pr.ChangedProtectedFiles = nil
 		return nil
@@ -601,7 +593,7 @@ func checkPullFilesProtection(ctx context.Context, pr *issues_model.PullRequest,
 		return nil
 	}
 
-	pr.ChangedProtectedFiles, err = CheckFileProtection(gitRepo, pr.HeadBranch, pr.MergeBase, "tracking", pb.GetProtectedFilePatterns(), 10, os.Environ())
+	pr.ChangedProtectedFiles, err = CheckFileProtection(ctx, repoPath, pr.MergeBase, pr.HeadCommitID, pb.GetProtectedFilePatterns(), 10, os.Environ())
 	if err != nil && !IsErrFilePathProtected(err) {
 		return err
 	}

services/pull/pull.go

@@ -30,6 +30,7 @@ import (
 	"code.gitea.io/gitea/modules/globallock"
 	"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"
@@ -86,16 +87,12 @@ func NewPullRequest(ctx context.Context, opts *NewPullRequestOptions) error {
 		}
 	}
 
-	prCtx, cancel, err := createTemporaryRepoForPR(ctx, pr)
-	if err != nil {
-		if !git_model.IsErrBranchNotExist(err) {
-			log.Error("CreateTemporaryRepoForPR %-v: %v", pr, err)
-		}
-		return err
-	}
-	defer cancel()
+	ctx, _, finished := process.GetManager().AddContext(ctx, fmt.Sprintf("testPullRequestBranchMergeable: %s", pr))
+	defer finished()
 
-	if err := testPullRequestTmpRepoBranchMergeable(ctx, prCtx, pr); err != nil {
+	// the pull request haven't been created
+	err := checkPullRequestMergeableAndUpdateStatus(ctx, pr)
+	if err != nil {
 		return err
 	}
 
@@ -290,8 +287,11 @@ func ChangeTargetBranch(ctx context.Context, pr *issues_model.PullRequest, doer
 	oldBranch := pr.BaseBranch
 	pr.BaseBranch = targetBranch
 
+	ctx, _, finished := process.GetManager().AddContext(ctx, fmt.Sprintf("testPullRequestBranchMergeable: %s", pr))
+	defer finished()
+
 	// Refresh patch
-	if err := testPullRequestBranchMergeable(pr); err != nil {
+	if err := checkPullRequestMergeableAndUpdateStatus(ctx, pr); err != nil {
 		return err
 	}
 

tests/integration/pull_comment_test.go

@@ -13,6 +13,8 @@ import (
 
 	issues_model "code.gitea.io/gitea/models/issues"
 	"code.gitea.io/gitea/models/unittest"
+	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/test"
 	issues_service "code.gitea.io/gitea/services/issue"
 
 	"github.com/stretchr/testify/assert"
@@ -96,14 +98,40 @@ func testPullCommentRetarget(t *testing.T, u *url.URL, session *TestSession) {
 	testWaitForPullRequestStatus(t, &issues_model.Issue{Title: testPRTitle}, issues_model.PullRequestStatusMergeable)
 }
 
-func TestPullComment(t *testing.T) {
+func TestPullComment_MergeTree(t *testing.T) {
 	onGiteaRun(t, func(t *testing.T, u *url.URL) {
 		session := loginUser(t, "user1")
 		testCreateBranch(t, session, "user2", "repo1", "branch/master", "test-branch/rebase", http.StatusSeeOther)
 		testCreateBranch(t, session, "user2", "repo1", "branch/master", "test-branch/retarget", http.StatusSeeOther)
 		testRepoFork(t, session, "user2", "repo1", "user1", "repo1", "")
 
-		t.Run("RebaseComment", func(t *testing.T) { testPullCommentRebase(t, u, session) })
-		t.Run("RetargetComment", func(t *testing.T) { testPullCommentRetarget(t, u, session) })
+		t.Run("RebaseComment_MergeTree", func(t *testing.T) {
+			defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, true)()
+			testPullCommentRebase(t, u, session)
+		})
+
+		t.Run("RetargetComment_MergeTree", func(t *testing.T) {
+			defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, true)()
+			testPullCommentRetarget(t, u, session)
+		})
+	})
+}
+
+func TestPullComment_TmpRepo(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, u *url.URL) {
+		session := loginUser(t, "user1")
+		testCreateBranch(t, session, "user2", "repo1", "branch/master", "test-branch/rebase", http.StatusSeeOther)
+		testCreateBranch(t, session, "user2", "repo1", "branch/master", "test-branch/retarget", http.StatusSeeOther)
+		testRepoFork(t, session, "user2", "repo1", "user1", "repo1", "")
+
+		t.Run("RebaseComment_TmpRepo", func(t *testing.T) {
+			defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, false)()
+			testPullCommentRebase(t, u, session)
+		})
+
+		t.Run("RetargetComment_TmpRepo", func(t *testing.T) {
+			defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, false)()
+			testPullCommentRetarget(t, u, session)
+		})
 	})
 }

tests/integration/pull_commit_test.go

@@ -4,9 +4,18 @@
 package integration
 
 import (
+	"fmt"
 	"net/http"
+	"net/url"
+	"path"
 	"testing"
 
+	auth_model "code.gitea.io/gitea/models/auth"
+	git_model "code.gitea.io/gitea/models/git"
+	repo_model "code.gitea.io/gitea/models/repo"
+	"code.gitea.io/gitea/models/unittest"
+	"code.gitea.io/gitea/modules/commitstatus"
+	api "code.gitea.io/gitea/modules/structs"
 	pull_service "code.gitea.io/gitea/services/pull"
 	"code.gitea.io/gitea/tests"
 
@@ -39,3 +48,98 @@ func TestListPullCommits(t *testing.T) {
 		assert.Contains(t, resp.Body.String(), `<td class="lines-code lines-code-new"><code class="code-inner"># repo1</code>`)
 	})
 }
+
+func TestPullCreate_CommitStatus(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, u *url.URL) {
+		session := loginUser(t, "user1")
+		testRepoFork(t, session, "user2", "repo1", "user1", "repo1", "")
+		testEditFileToNewBranch(t, session, "user1", "repo1", "master", "status1", "README.md", "status1")
+
+		url := path.Join("user1", "repo1", "compare", "master...status1")
+		req := NewRequestWithValues(t, "POST", url,
+			map[string]string{
+				"_csrf": GetUserCSRFToken(t, session),
+				"title": "pull request from status1",
+			},
+		)
+		session.MakeRequest(t, req, http.StatusOK)
+
+		req = NewRequest(t, "GET", "/user1/repo1/pulls")
+		resp := session.MakeRequest(t, req, http.StatusOK)
+		NewHTMLParser(t, resp.Body)
+
+		// Request repository commits page
+		req = NewRequest(t, "GET", "/user1/repo1/pulls/1/commits")
+		resp = session.MakeRequest(t, req, http.StatusOK)
+		doc := NewHTMLParser(t, resp.Body)
+
+		// Get first commit URL
+		commitURL, exists := doc.doc.Find("#commits-table tbody tr td.sha a").Last().Attr("href")
+		assert.True(t, exists)
+		assert.NotEmpty(t, commitURL)
+
+		commitID := path.Base(commitURL)
+
+		statusList := []commitstatus.CommitStatusState{
+			commitstatus.CommitStatusPending,
+			commitstatus.CommitStatusError,
+			commitstatus.CommitStatusFailure,
+			commitstatus.CommitStatusSuccess,
+			commitstatus.CommitStatusWarning,
+		}
+
+		statesIcons := map[commitstatus.CommitStatusState]string{
+			commitstatus.CommitStatusPending: "octicon-dot-fill",
+			commitstatus.CommitStatusSuccess: "octicon-check",
+			commitstatus.CommitStatusError:   "gitea-exclamation",
+			commitstatus.CommitStatusFailure: "octicon-x",
+			commitstatus.CommitStatusWarning: "gitea-exclamation",
+		}
+
+		testCtx := NewAPITestContext(t, "user1", "repo1", auth_model.AccessTokenScopeWriteRepository)
+
+		// Update commit status, and check if icon is updated as well
+		for _, status := range statusList {
+			// Call API to add status for commit
+			t.Run("CreateStatus", doAPICreateCommitStatus(testCtx, commitID, api.CreateStatusOption{
+				State:       status,
+				TargetURL:   "http://test.ci/",
+				Description: "",
+				Context:     "testci",
+			}))
+
+			req = NewRequest(t, "GET", "/user1/repo1/pulls/1/commits")
+			resp = session.MakeRequest(t, req, http.StatusOK)
+			doc = NewHTMLParser(t, resp.Body)
+
+			commitURL, exists = doc.doc.Find("#commits-table tbody tr td.sha a").Last().Attr("href")
+			assert.True(t, exists)
+			assert.NotEmpty(t, commitURL)
+			assert.Equal(t, commitID, path.Base(commitURL))
+
+			cls, ok := doc.doc.Find("#commits-table tbody tr td.message .commit-status").Last().Attr("class")
+			assert.True(t, ok)
+			assert.Contains(t, cls, statesIcons[status])
+		}
+
+		repo1 := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{OwnerName: "user1", Name: "repo1"})
+		css := unittest.AssertExistsAndLoadBean(t, &git_model.CommitStatusSummary{RepoID: repo1.ID, SHA: commitID})
+		assert.Equal(t, commitstatus.CommitStatusSuccess, css.State)
+	})
+}
+
+func doAPICreateCommitStatus(ctx APITestContext, commitID string, data api.CreateStatusOption) func(*testing.T) {
+	return func(t *testing.T) {
+		req := NewRequestWithJSON(
+			t,
+			http.MethodPost,
+			fmt.Sprintf("/api/v1/repos/%s/%s/statuses/%s", ctx.Username, ctx.Reponame, commitID),
+			data,
+		).AddTokenAuth(ctx.Token)
+		if ctx.ExpectedCode != 0 {
+			ctx.Session.MakeRequest(t, req, ctx.ExpectedCode)
+			return
+		}
+		ctx.Session.MakeRequest(t, req, http.StatusCreated)
+	}
+}

tests/integration/pull_merge_test.go

@@ -36,9 +36,7 @@ import (
 	"code.gitea.io/gitea/services/automerge"
 	"code.gitea.io/gitea/services/automergequeue"
 	pull_service "code.gitea.io/gitea/services/pull"
-	repo_service "code.gitea.io/gitea/services/repository"
 	commitstatus_service "code.gitea.io/gitea/services/repository/commitstatus"
-	files_service "code.gitea.io/gitea/services/repository/files"
 
 	"github.com/stretchr/testify/assert"
 )
@@ -523,86 +521,6 @@ func TestCantFastForwardOnlyMergeDiverging(t *testing.T) {
 	})
 }
 
-func TestConflictChecking(t *testing.T) {
-	onGiteaRun(t, func(t *testing.T, giteaURL *url.URL) {
-		user := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 2})
-
-		// Create new clean repo to test conflict checking.
-		baseRepo, err := repo_service.CreateRepository(t.Context(), user, user, repo_service.CreateRepoOptions{
-			Name:          "conflict-checking",
-			Description:   "Tempo repo",
-			AutoInit:      true,
-			Readme:        "Default",
-			DefaultBranch: "main",
-		})
-		assert.NoError(t, err)
-		assert.NotEmpty(t, baseRepo)
-
-		// create a commit on new branch.
-		_, err = files_service.ChangeRepoFiles(t.Context(), baseRepo, user, &files_service.ChangeRepoFilesOptions{
-			Files: []*files_service.ChangeRepoFile{
-				{
-					Operation:     "create",
-					TreePath:      "important_file",
-					ContentReader: strings.NewReader("Just a non-important file"),
-				},
-			},
-			Message:   "Add a important file",
-			OldBranch: "main",
-			NewBranch: "important-secrets",
-		})
-		assert.NoError(t, err)
-
-		// create a commit on main branch.
-		_, err = files_service.ChangeRepoFiles(t.Context(), baseRepo, user, &files_service.ChangeRepoFilesOptions{
-			Files: []*files_service.ChangeRepoFile{
-				{
-					Operation:     "create",
-					TreePath:      "important_file",
-					ContentReader: strings.NewReader("Not the same content :P"),
-				},
-			},
-			Message:   "Add a important file",
-			OldBranch: "main",
-			NewBranch: "main",
-		})
-		assert.NoError(t, err)
-
-		// create Pull to merge the important-secrets branch into main branch.
-		pullIssue := &issues_model.Issue{
-			RepoID:   baseRepo.ID,
-			Title:    "PR with conflict!",
-			PosterID: user.ID,
-			Poster:   user,
-			IsPull:   true,
-		}
-
-		pullRequest := &issues_model.PullRequest{
-			HeadRepoID: baseRepo.ID,
-			BaseRepoID: baseRepo.ID,
-			HeadBranch: "important-secrets",
-			BaseBranch: "main",
-			HeadRepo:   baseRepo,
-			BaseRepo:   baseRepo,
-			Type:       issues_model.PullRequestGitea,
-		}
-		prOpts := &pull_service.NewPullRequestOptions{Repo: baseRepo, Issue: pullIssue, PullRequest: pullRequest}
-		err = pull_service.NewPullRequest(t.Context(), prOpts)
-		assert.NoError(t, err)
-
-		issue := unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{Title: "PR with conflict!"})
-		assert.NoError(t, issue.LoadPullRequest(t.Context()))
-		conflictingPR := issue.PullRequest
-
-		// Ensure conflictedFiles is populated.
-		assert.Len(t, conflictingPR.ConflictedFiles, 1)
-		// Check if status is correct.
-		assert.Equal(t, issues_model.PullRequestStatusConflict, conflictingPR.Status)
-		// Ensure that mergeable returns false
-		assert.False(t, conflictingPR.Mergeable(t.Context()))
-	})
-}
-
 func TestPullRetargetChildOnBranchDelete(t *testing.T) {
 	onGiteaRun(t, func(t *testing.T, giteaURL *url.URL) {
 		session := loginUser(t, "user1")

tests/integration/pull_status_test.go

@@ -11,115 +11,20 @@ import (
 	"strings"
 	"testing"
 
-	auth_model "code.gitea.io/gitea/models/auth"
-	git_model "code.gitea.io/gitea/models/git"
-	"code.gitea.io/gitea/models/issues"
+	issues_model "code.gitea.io/gitea/models/issues"
 	repo_model "code.gitea.io/gitea/models/repo"
 	"code.gitea.io/gitea/models/unittest"
-	"code.gitea.io/gitea/modules/commitstatus"
+	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/git/gitcmd"
 	"code.gitea.io/gitea/modules/setting"
-	api "code.gitea.io/gitea/modules/structs"
 	"code.gitea.io/gitea/modules/test"
-	"code.gitea.io/gitea/services/pull"
+	pull_service "code.gitea.io/gitea/services/pull"
+	repo_service "code.gitea.io/gitea/services/repository"
 
 	"github.com/stretchr/testify/assert"
 )
 
-func TestPullCreate_CommitStatus(t *testing.T) {
-	onGiteaRun(t, func(t *testing.T, u *url.URL) {
-		session := loginUser(t, "user1")
-		testRepoFork(t, session, "user2", "repo1", "user1", "repo1", "")
-		testEditFileToNewBranch(t, session, "user1", "repo1", "master", "status1", "README.md", "status1")
-
-		url := path.Join("user1", "repo1", "compare", "master...status1")
-		req := NewRequestWithValues(t, "POST", url,
-			map[string]string{
-				"_csrf": GetUserCSRFToken(t, session),
-				"title": "pull request from status1",
-			},
-		)
-		session.MakeRequest(t, req, http.StatusOK)
-
-		req = NewRequest(t, "GET", "/user1/repo1/pulls")
-		resp := session.MakeRequest(t, req, http.StatusOK)
-		NewHTMLParser(t, resp.Body)
-
-		// Request repository commits page
-		req = NewRequest(t, "GET", "/user1/repo1/pulls/1/commits")
-		resp = session.MakeRequest(t, req, http.StatusOK)
-		doc := NewHTMLParser(t, resp.Body)
-
-		// Get first commit URL
-		commitURL, exists := doc.doc.Find("#commits-table tbody tr td.sha a").Last().Attr("href")
-		assert.True(t, exists)
-		assert.NotEmpty(t, commitURL)
-
-		commitID := path.Base(commitURL)
-
-		statusList := []commitstatus.CommitStatusState{
-			commitstatus.CommitStatusPending,
-			commitstatus.CommitStatusError,
-			commitstatus.CommitStatusFailure,
-			commitstatus.CommitStatusSuccess,
-			commitstatus.CommitStatusWarning,
-		}
-
-		statesIcons := map[commitstatus.CommitStatusState]string{
-			commitstatus.CommitStatusPending: "octicon-dot-fill",
-			commitstatus.CommitStatusSuccess: "octicon-check",
-			commitstatus.CommitStatusError:   "gitea-exclamation",
-			commitstatus.CommitStatusFailure: "octicon-x",
-			commitstatus.CommitStatusWarning: "gitea-exclamation",
-		}
-
-		testCtx := NewAPITestContext(t, "user1", "repo1", auth_model.AccessTokenScopeWriteRepository)
-
-		// Update commit status, and check if icon is updated as well
-		for _, status := range statusList {
-			// Call API to add status for commit
-			t.Run("CreateStatus", doAPICreateCommitStatus(testCtx, commitID, api.CreateStatusOption{
-				State:       status,
-				TargetURL:   "http://test.ci/",
-				Description: "",
-				Context:     "testci",
-			}))
-
-			req = NewRequest(t, "GET", "/user1/repo1/pulls/1/commits")
-			resp = session.MakeRequest(t, req, http.StatusOK)
-			doc = NewHTMLParser(t, resp.Body)
-
-			commitURL, exists = doc.doc.Find("#commits-table tbody tr td.sha a").Last().Attr("href")
-			assert.True(t, exists)
-			assert.NotEmpty(t, commitURL)
-			assert.Equal(t, commitID, path.Base(commitURL))
-
-			cls, ok := doc.doc.Find("#commits-table tbody tr td.message .commit-status").Last().Attr("class")
-			assert.True(t, ok)
-			assert.Contains(t, cls, statesIcons[status])
-		}
-
-		repo1 := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{OwnerName: "user1", Name: "repo1"})
-		css := unittest.AssertExistsAndLoadBean(t, &git_model.CommitStatusSummary{RepoID: repo1.ID, SHA: commitID})
-		assert.Equal(t, commitstatus.CommitStatusSuccess, css.State)
-	})
-}
-
-func doAPICreateCommitStatus(ctx APITestContext, commitID string, data api.CreateStatusOption) func(*testing.T) {
-	return func(t *testing.T) {
-		req := NewRequestWithJSON(
-			t,
-			http.MethodPost,
-			fmt.Sprintf("/api/v1/repos/%s/%s/statuses/%s", ctx.Username, ctx.Reponame, commitID),
-			data,
-		).AddTokenAuth(ctx.Token)
-		if ctx.ExpectedCode != 0 {
-			ctx.Session.MakeRequest(t, req, ctx.ExpectedCode)
-			return
-		}
-		ctx.Session.MakeRequest(t, req, http.StatusCreated)
-	}
-}
-
 func TestPullCreate_EmptyChangesWithDifferentCommits(t *testing.T) {
 	// Merge must continue if commits SHA are different, even if content is same
 	// Reason: gitflow and merging master back into develop, where is high possibility, there are no changes
@@ -174,16 +79,16 @@ func TestPullCreate_EmptyChangesWithSameCommits(t *testing.T) {
 func TestPullStatusDelayCheck(t *testing.T) {
 	onGiteaRun(t, func(t *testing.T, u *url.URL) {
 		defer test.MockVariableValue(&setting.Repository.PullRequest.DelayCheckForInactiveDays, 1)()
-		defer test.MockVariableValue(&pull.AddPullRequestToCheckQueue)()
+		defer test.MockVariableValue(&pull_service.AddPullRequestToCheckQueue)()
 
 		session := loginUser(t, "user2")
 
-		run := func(t *testing.T, fn func(*testing.T)) (issue3 *issues.Issue, checkedPrID int64) {
-			pull.AddPullRequestToCheckQueue = func(prID int64) {
+		run := func(t *testing.T, fn func(*testing.T)) (issue3 *issues_model.Issue, checkedPrID int64) {
+			pull_service.AddPullRequestToCheckQueue = func(prID int64) {
 				checkedPrID = prID
 			}
 			fn(t)
-			issue3 = unittest.AssertExistsAndLoadBean(t, &issues.Issue{RepoID: 1, Index: 3})
+			issue3 = unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{RepoID: 1, Index: 3})
 			_ = issue3.LoadPullRequest(t.Context())
 			return issue3, checkedPrID
 		}
@@ -201,7 +106,7 @@ func TestPullStatusDelayCheck(t *testing.T) {
 
 		// PR issue3 is merageable at the beginning
 		issue3, checkedPrID := run(t, func(t *testing.T) {})
-		assert.Equal(t, issues.PullRequestStatusMergeable, issue3.PullRequest.Status)
+		assert.Equal(t, issues_model.PullRequestStatusMergeable, issue3.PullRequest.Status)
 		assert.Zero(t, checkedPrID)
 		assertReloadingInterval(t, "") // the PR is mergeable, so no need to reload the merge box
 
@@ -213,7 +118,7 @@ func TestPullStatusDelayCheck(t *testing.T) {
 		issue3, checkedPrID = run(t, func(t *testing.T) {
 			testEditFile(t, session, "user2", "repo1", "master", "README.md", "new content 1")
 		})
-		assert.Equal(t, issues.PullRequestStatusChecking, issue3.PullRequest.Status)
+		assert.Equal(t, issues_model.PullRequestStatusChecking, issue3.PullRequest.Status)
 		assert.Zero(t, checkedPrID)
 		assertReloadingInterval(t, "2000") // the PR status is "checking", so try to reload the merge box
 
@@ -222,14 +127,14 @@ func TestPullStatusDelayCheck(t *testing.T) {
 			req := NewRequest(t, "GET", "/user2/repo1/pulls/3")
 			session.MakeRequest(t, req, http.StatusOK)
 		})
-		assert.Equal(t, issues.PullRequestStatusChecking, issue3.PullRequest.Status)
+		assert.Equal(t, issues_model.PullRequestStatusChecking, issue3.PullRequest.Status)
 		assert.Equal(t, issue3.PullRequest.ID, checkedPrID)
 
 		// when base branch changes, still so no real check
 		issue3, checkedPrID = run(t, func(t *testing.T) {
 			testEditFile(t, session, "user2", "repo1", "master", "README.md", "new content 2")
 		})
-		assert.Equal(t, issues.PullRequestStatusChecking, issue3.PullRequest.Status)
+		assert.Equal(t, issues_model.PullRequestStatusChecking, issue3.PullRequest.Status)
 		assert.Zero(t, checkedPrID)
 
 		// then allow to check PRs without delay, when base branch changes, the PRs will be checked
@@ -237,7 +142,407 @@ func TestPullStatusDelayCheck(t *testing.T) {
 		issue3, checkedPrID = run(t, func(t *testing.T) {
 			testEditFile(t, session, "user2", "repo1", "master", "README.md", "new content 3")
 		})
-		assert.Equal(t, issues.PullRequestStatusChecking, issue3.PullRequest.Status)
+		assert.Equal(t, issues_model.PullRequestStatusChecking, issue3.PullRequest.Status)
 		assert.Equal(t, issue3.PullRequest.ID, checkedPrID)
 	})
 }
+
+func Test_PullRequestStatusChecking_Mergeable_MergeTree(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, giteaURL *url.URL) {
+		defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, true)()
+		testPullRequestStatusCheckingMergeable(t)
+	})
+}
+
+func Test_PullRequestStatusChecking_Mergeable_TmpRepo(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, giteaURL *url.URL) {
+		defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, false)()
+		testPullRequestStatusCheckingMergeable(t)
+	})
+}
+
+func testPullRequestStatusCheckingMergeable(t *testing.T) {
+	user := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 2})
+	session := loginUser(t, user.Name)
+
+	// Create new clean repo to test conflict checking.
+	baseRepo, err := repo_service.CreateRepository(t.Context(), user, user, repo_service.CreateRepoOptions{
+		Name:          "conflict-checking",
+		Description:   "Tempo repo",
+		AutoInit:      true,
+		Readme:        "Default",
+		DefaultBranch: "main",
+	})
+	assert.NoError(t, err)
+	assert.NotEmpty(t, baseRepo)
+
+	// create a commit on new branch.
+	testCreateFile(t, session, baseRepo.OwnerName, baseRepo.Name, "main", "important-secrets", "important_file", "Just a non-important file")
+
+	// create Pull to merge the important-secrets branch into main branch.
+	resp := testPullCreateDirectly(t, session, createPullRequestOptions{
+		BaseRepoOwner: baseRepo.OwnerName,
+		BaseRepoName:  baseRepo.Name,
+		BaseBranch:    "main",
+		HeadRepoOwner: baseRepo.OwnerName,
+		HeadRepoName:  baseRepo.Name,
+		HeadBranch:    "important-secrets",
+		Title:         "PR with no conflict",
+	})
+	// check the redirected URL
+	url := test.RedirectURL(resp)
+	assert.Regexp(t, fmt.Sprintf("^/%s/pulls/[0-9]*$", baseRepo.FullName()), url)
+
+	issue := unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{Title: "PR with no conflict"})
+	assert.NoError(t, issue.LoadPullRequest(t.Context()))
+	conflictingPR := issue.PullRequest
+
+	// Ensure conflictedFiles is populated.
+	assert.Empty(t, conflictingPR.ConflictedFiles)
+	// Check if status is correct.
+	assert.Equal(t, issues_model.PullRequestStatusMergeable, conflictingPR.Status)
+	// Ensure that mergeable returns true
+	assert.True(t, conflictingPR.Mergeable(t.Context()))
+}
+
+func Test_PullRequestStatusChecking_Conflicted_MergeTree(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, giteaURL *url.URL) {
+		defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, true)()
+		testPullRequestStatusCheckingConflicted(t)
+	})
+}
+
+func Test_PullRequestStatusChecking_Conflicted_TmpRepo(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, giteaURL *url.URL) {
+		defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, false)()
+		testPullRequestStatusCheckingConflicted(t)
+	})
+}
+
+func testPullRequestStatusCheckingConflicted(t *testing.T) {
+	user := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 2})
+	session := loginUser(t, user.Name)
+
+	// Create new clean repo to test conflict checking.
+	baseRepo, err := repo_service.CreateRepository(t.Context(), user, user, repo_service.CreateRepoOptions{
+		Name:          "conflict-checking",
+		Description:   "Tempo repo",
+		AutoInit:      true,
+		Readme:        "Default",
+		DefaultBranch: "main",
+	})
+	assert.NoError(t, err)
+	assert.NotEmpty(t, baseRepo)
+
+	// create a commit on new branch.
+	testCreateFile(t, session, baseRepo.OwnerName, baseRepo.Name, "main", "important-secrets", "important_file", "Just a non-important file")
+
+	// create a commit on main branch.
+	testCreateFile(t, session, baseRepo.OwnerName, baseRepo.Name, "main", "main", "important_file", "Not the same content :P")
+
+	// create Pull to merge the important-secrets branch into main branch.
+	resp := testPullCreateDirectly(t, session, createPullRequestOptions{
+		BaseRepoOwner: baseRepo.OwnerName,
+		BaseRepoName:  baseRepo.Name,
+		BaseBranch:    "main",
+		HeadRepoOwner: baseRepo.OwnerName,
+		HeadRepoName:  baseRepo.Name,
+		HeadBranch:    "important-secrets",
+		Title:         "PR with conflict!",
+	})
+	// check the redirected URL
+	url := test.RedirectURL(resp)
+	assert.Regexp(t, fmt.Sprintf("^/%s/pulls/[0-9]*$", baseRepo.FullName()), url)
+
+	issue := unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{Title: "PR with conflict!"})
+	assert.NoError(t, issue.LoadPullRequest(t.Context()))
+	conflictingPR := issue.PullRequest
+
+	// Ensure conflictedFiles is populated.
+	assert.Equal(t, []string{"important_file"}, conflictingPR.ConflictedFiles)
+	// Check if status is correct.
+	assert.Equal(t, issues_model.PullRequestStatusConflict, conflictingPR.Status)
+	// Ensure that mergeable returns false
+	assert.False(t, conflictingPR.Mergeable(t.Context()))
+}
+
+func Test_PullRequestStatusCheckingCrossRepo_Mergeable_MergeTree(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, giteaURL *url.URL) {
+		defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, true)()
+		testPullRequestStatusCheckingCrossRepoMergeable(t, giteaURL)
+	})
+}
+
+func Test_PullRequestStatusCheckingCrossRepo_Mergeable_TmpRepo(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, giteaURL *url.URL) {
+		defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, false)()
+		testPullRequestStatusCheckingCrossRepoMergeable(t, giteaURL)
+	})
+}
+
+func testPullRequestStatusCheckingCrossRepoMergeable(t *testing.T, giteaURL *url.URL) {
+	user := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 2})
+	session := loginUser(t, user.Name)
+
+	// Create new clean repo to test conflict checking.
+	baseRepo, err := repo_service.CreateRepository(t.Context(), user, user, repo_service.CreateRepoOptions{
+		Name:          "conflict-checking",
+		Description:   "Tempo repo",
+		AutoInit:      true,
+		Readme:        "Default",
+		DefaultBranch: "main",
+	})
+	assert.NoError(t, err)
+	assert.NotEmpty(t, baseRepo)
+
+	testRepoFork(t, session, baseRepo.OwnerName, baseRepo.Name, "org3", "conflict-checking", "main")
+
+	forkRepo := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{OwnerName: "org3", Name: "conflict-checking"})
+
+	// create a commit on new branch of forked repository
+	testCreateFile(t, session, forkRepo.OwnerName, forkRepo.Name, "main", "important-secrets", "important_file", "Just a non-important file")
+
+	// create Pull to merge the important-secrets branch into main branch.
+	resp := testPullCreateDirectly(t, session, createPullRequestOptions{
+		BaseRepoOwner: baseRepo.OwnerName,
+		BaseRepoName:  baseRepo.Name,
+		BaseBranch:    "main",
+		HeadRepoOwner: forkRepo.OwnerName,
+		HeadRepoName:  forkRepo.Name,
+		HeadBranch:    "important-secrets",
+		Title:         "PR with no conflict",
+	})
+	// check the redirected URL
+	url := test.RedirectURL(resp)
+	assert.Regexp(t, fmt.Sprintf("^/%s/pulls/[0-9]*$", baseRepo.FullName()), url)
+
+	issue := unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{Title: "PR with no conflict"})
+	assert.NoError(t, issue.LoadPullRequest(t.Context()))
+	conflictingPR := issue.PullRequest
+
+	// Ensure conflictedFiles is populated.
+	assert.Empty(t, conflictingPR.ConflictedFiles)
+	// Check if status is correct.
+	assert.Equal(t, issues_model.PullRequestStatusMergeable, conflictingPR.Status)
+	// Ensure that mergeable returns true
+	assert.True(t, conflictingPR.Mergeable(t.Context()))
+}
+
+func Test_PullRequestStatusCheckingCrossRepo_Conflicted_MergeTree(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, giteaURL *url.URL) {
+		defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, true)()
+		testPullRequestStatusCheckingCrossRepoConflicted(t, giteaURL)
+	})
+}
+
+func Test_PullRequestStatusCheckingCrossRepo_Conflicted_TmpRepo(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, giteaURL *url.URL) {
+		defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, false)()
+		testPullRequestStatusCheckingCrossRepoConflicted(t, giteaURL)
+	})
+}
+
+func testPullRequestStatusCheckingCrossRepoConflicted(t *testing.T, giteaURL *url.URL) {
+	user := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 2})
+	session := loginUser(t, user.Name)
+
+	// Create new clean repo to test conflict checking.
+	baseRepo, err := repo_service.CreateRepository(t.Context(), user, user, repo_service.CreateRepoOptions{
+		Name:          "conflict-checking",
+		Description:   "Tempo repo",
+		AutoInit:      true,
+		Readme:        "Default",
+		DefaultBranch: "main",
+	})
+	assert.NoError(t, err)
+	assert.NotEmpty(t, baseRepo)
+
+	testRepoFork(t, session, baseRepo.OwnerName, baseRepo.Name, "org3", "conflict-checking", "main")
+
+	forkRepo := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{OwnerName: "org3", Name: "conflict-checking"})
+
+	// create a commit on new branch of forked repository
+	testCreateFile(t, session, forkRepo.OwnerName, forkRepo.Name, "main", "important-secrets", "important_file", "Just a non-important file")
+
+	// create a commit on main branch of base repository.
+	testCreateFile(t, session, baseRepo.OwnerName, baseRepo.Name, "main", "main", "important_file", "Not the same content :P")
+
+	// create Pull to merge the important-secrets branch into main branch.
+	resp := testPullCreateDirectly(t, session, createPullRequestOptions{
+		BaseRepoOwner: baseRepo.OwnerName,
+		BaseRepoName:  baseRepo.Name,
+		BaseBranch:    "main",
+		HeadRepoOwner: forkRepo.OwnerName,
+		HeadRepoName:  forkRepo.Name,
+		HeadBranch:    "important-secrets",
+		Title:         "PR with conflict!",
+	})
+	// check the redirected URL
+	url := test.RedirectURL(resp)
+	assert.Regexp(t, fmt.Sprintf("^/%s/pulls/[0-9]*$", baseRepo.FullName()), url)
+
+	issue := unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{Title: "PR with conflict!"})
+	assert.NoError(t, issue.LoadPullRequest(t.Context()))
+	conflictingPR := issue.PullRequest
+
+	// Ensure conflictedFiles is populated.
+	assert.Equal(t, []string{"important_file"}, conflictingPR.ConflictedFiles)
+	// Check if status is correct.
+	assert.Equal(t, issues_model.PullRequestStatusConflict, conflictingPR.Status)
+	// Ensure that mergeable returns false
+	assert.False(t, conflictingPR.Mergeable(t.Context()))
+}
+
+func Test_PullRequest_AGit_StatusChecking_Mergeable_MergeTree(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, giteaURL *url.URL) {
+		defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, true)()
+
+		testPullRequestAGitStatusCheckingMergeable(t, giteaURL)
+	})
+}
+
+func Test_PullRequest_AGit_StatusChecking_Mergeable_TmpRepo(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, giteaURL *url.URL) {
+		defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, false)()
+
+		testPullRequestAGitStatusCheckingMergeable(t, giteaURL)
+	})
+}
+
+func testPullRequestAGitStatusCheckingMergeable(t *testing.T, giteaURL *url.URL) {
+	user := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 2})
+
+	// Create new clean repo to test conflict checking.
+	baseRepo, err := repo_service.CreateRepository(t.Context(), user, user, repo_service.CreateRepoOptions{
+		Name:          "conflict-checking",
+		Description:   "Tempo repo",
+		AutoInit:      true,
+		Readme:        "Default",
+		DefaultBranch: "main",
+	})
+	assert.NoError(t, err)
+	assert.NotEmpty(t, baseRepo)
+
+	// add something in local repository and push it to remote
+	dstPath := t.TempDir()
+	repoURL := *giteaURL
+	repoURL.Path = baseRepo.FullName() + ".git"
+	repoURL.User = url.UserPassword("user2", userPassword)
+	doGitClone(dstPath, &repoURL)(t)
+
+	gitRepo, err := git.OpenRepository(t.Context(), dstPath)
+	assert.NoError(t, err)
+	defer gitRepo.Close()
+
+	doGitCreateBranch(dstPath, "test-agit-push")(t)
+
+	_, err = generateCommitWithNewData(t.Context(), testFileSizeSmall, dstPath, "user2@example.com", "User Two", "branch-data-file-")
+	assert.NoError(t, err)
+
+	// push to create an agit pull request
+	err = gitcmd.NewCommand("push", "origin",
+		"-o", "title=agit-test-title", "-o", "description=agit-test-description",
+		"-o", "topic=head-branch-name",
+		"HEAD:refs/for/main",
+	).WithDir(dstPath).Run(t.Context())
+	assert.NoError(t, err)
+
+	issue := unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{
+		RepoID: baseRepo.ID,
+		Title:  "agit-test-title",
+	})
+	assert.NoError(t, issue.LoadPullRequest(t.Context()))
+	conflictingPR := issue.PullRequest
+
+	// Ensure conflictedFiles is populated.
+	assert.Empty(t, conflictingPR.ConflictedFiles)
+	// Check if status is correct.
+	assert.Equal(t, issues_model.PullRequestStatusMergeable, conflictingPR.Status)
+	// Ensure that mergeable returns true
+	assert.True(t, conflictingPR.Mergeable(t.Context()))
+}
+
+func Test_PullRequest_AGit_StatusChecking_Conflicted_MergeTree(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, giteaURL *url.URL) {
+		defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, true)()
+
+		testPullRequestAGitStatusCheckingConflicted(t, giteaURL)
+	})
+}
+
+func Test_PullRequest_AGit_StatusChecking_Conflicted_TmpRepo(t *testing.T) {
+	onGiteaRun(t, func(t *testing.T, giteaURL *url.URL) {
+		defer test.MockVariableValue(&git.DefaultFeatures().SupportGitMergeTree, false)()
+
+		testPullRequestAGitStatusCheckingConflicted(t, giteaURL)
+	})
+}
+
+func testPullRequestAGitStatusCheckingConflicted(t *testing.T, giteaURL *url.URL) {
+	user := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 2})
+
+	// Create new clean repo to test conflict checking.
+	baseRepo, err := repo_service.CreateRepository(t.Context(), user, user, repo_service.CreateRepoOptions{
+		Name:          "conflict-checking",
+		Description:   "Tempo repo",
+		AutoInit:      true,
+		Readme:        "Default",
+		DefaultBranch: "main",
+	})
+	assert.NoError(t, err)
+	assert.NotEmpty(t, baseRepo)
+
+	// add something in local repository and push it to remote
+	dstPath := t.TempDir()
+	repoURL := *giteaURL
+	repoURL.Path = baseRepo.FullName() + ".git"
+	repoURL.User = url.UserPassword("user2", userPassword)
+	doGitClone(dstPath, &repoURL)(t)
+
+	gitRepo, err := git.OpenRepository(t.Context(), dstPath)
+	assert.NoError(t, err)
+	defer gitRepo.Close()
+
+	// create agit branch from current commit
+	doGitCreateBranch(dstPath, "test-agit-push")(t)
+
+	doGitCheckoutWriteFileCommit(localGitAddCommitOptions{
+		LocalRepoPath:   dstPath,
+		CheckoutBranch:  "main",
+		TreeFilePath:    "README.md",
+		TreeFileContent: "Some changes to README file to main cause conflict",
+	})(t)
+
+	err = gitcmd.NewCommand("push", "origin", "main").WithDir(dstPath).Run(t.Context())
+	assert.NoError(t, err)
+
+	// check out back to agit branch and change the same file
+	doGitCheckoutWriteFileCommit(localGitAddCommitOptions{
+		LocalRepoPath:   dstPath,
+		CheckoutBranch:  "test-agit-push",
+		TreeFilePath:    "README.md",
+		TreeFileContent: "Some changes to README file for agit branch",
+	})(t)
+
+	// push to create an agit pull request
+	err = gitcmd.NewCommand("push", "origin",
+		"-o", "title=agit-test-title", "-o", "description=agit-test-description",
+		"-o", "topic=head-branch-name",
+		"HEAD:refs/for/main",
+	).WithDir(dstPath).Run(t.Context())
+	assert.NoError(t, err)
+
+	issue := unittest.AssertExistsAndLoadBean(t, &issues_model.Issue{
+		RepoID: baseRepo.ID,
+		Title:  "agit-test-title",
+	})
+	assert.NoError(t, issue.LoadPullRequest(t.Context()))
+	conflictingPR := issue.PullRequest
+
+	// Ensure conflictedFiles is populated.
+	assert.Equal(t, []string{"README.md"}, conflictingPR.ConflictedFiles)
+	// Check if status is correct.
+	assert.Equal(t, issues_model.PullRequestStatusConflict, conflictingPR.Status)
+	// Ensure that mergeable returns false
+	assert.False(t, conflictingPR.Mergeable(t.Context()))
+}