From c13c3e269a523154eb0f9db090c35ab2ecb2caa6 Mon Sep 17 00:00:00 2001
From: yystopf <yystopf@163.com>
Date: Tue, 28 Jul 2026 11:23:04 +0800
Subject: [PATCH] =?UTF-8?q?=E4=BF=AE=E5=A4=8D=EF=BC=9Acompare=20diff=20?=
 =?UTF-8?q?=E4=B8=BA=E7=A9=BA?=
MIME-Version: 1.0
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---
 routers/hat/repo/repo.go | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/routers/hat/repo/repo.go b/routers/hat/repo/repo.go
index c1e308c..325b14d 100644
--- a/routers/hat/repo/repo.go
+++ b/routers/hat/repo/repo.go
@@ -48,7 +48,11 @@ func PrepareComapreDiff(
 
 	ctx.Data["CommitRepoLink"] = headRepo.Link()
 
-	headCommitID := headBranch
+	beforeCommitID := compareInfo.MergeBase
+	if compareInfo.DirectComparison() {
+		beforeCommitID = compareInfo.BaseCommitID
+	}
+	headCommitID := compareInfo.HeadCommitID
 	if ctx.Data["HeadIsCommit"] == false {
 		if ctx.Data["HeadIsTag"] == true {
 			headCommitID, err = headGitRepo.GetTagCommitID(headBranch)
@@ -73,8 +77,8 @@ func PrepareComapreDiff(
 	gitRepo, _ := gitea_git.OpenRepository(ctx, repoPath)
 	defer gitRepo.Close()
 
-	diff, err := gitdiff.GetDiffForAPI(ctx, gitRepo, &gitdiff.DiffOptions{
-		BeforeCommitID:     compareInfo.MergeBase,
+	diff, err := gitdiff.GetDiffForAPI(ctx, compareInfo.HeadGitRepo, &gitdiff.DiffOptions{
+		BeforeCommitID:     beforeCommitID,
 		AfterCommitID:      headCommitID,
 		SkipTo:             ctx.FormString("skip-to"),
 		MaxLines:           setting.Git.MaxGitDiffLines,
@@ -88,7 +92,7 @@ func PrepareComapreDiff(
 		return false
 	}
 
-	diffShortStat, err := gitdiff.GetDiffShortStat(ctx, ctx.Repo.Repository, gitRepo, compareInfo.MergeBase, headCommitID)
+	diffShortStat, err := gitdiff.GetDiffShortStat(ctx, compareInfo.HeadRepo, compareInfo.HeadGitRepo, beforeCommitID, headCommitID)
 	if err != nil {
 		ctx.APIErrorInternal(err)
 		return false
@@ -229,13 +233,13 @@ func CompareDiff(ctx *context.APIContext) {
 			})
 		} else {
 			path := util.PathEscapeSegments(ctx.FormString("filepath"))
-			headUser, headRepo, headGitRepo, compareInfo, baseBranch, headBranch := ParseCompareInfo(ctx)
+			headUser, _, headGitRepo, compareInfo, baseBranch, headBranch := ParseCompareInfo(ctx)
 			if ctx.Written() {
 				return
 			}
 			defer headGitRepo.Close()
 
-			_ = PrepareComapreDiff(ctx, headUser, headRepo, headGitRepo, compareInfo, baseBranch, headBranch, path)
+			_ = PrepareComapreDiff(ctx, headUser, compareInfo.HeadRepo, compareInfo.HeadGitRepo, compareInfo, baseBranch, headBranch, path)
 
 			result := make([]CompareCommit, 0)
 			for _, commit := range compareInfo.Commits {