From 5829522019fdf6e677dc6822809ddfb1af283836 Mon Sep 17 00:00:00 2001
From: Nicolas <bircni@icloud.com>
Date: Mon, 11 May 2026 20:07:23 +0200
Subject: [PATCH] fix show correct mergebase (#37656)
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## Summary

When comparing branches with **no common merge base** (e.g. unrelated
histories or orphan branches), `PageIsComparePull` is false and
`CommitCount` is zero. The compare template still showed
`repo.commits.nothing_to_compare`, which in German reads like the
branches are identical—even though the flash already explains there is
no merge base.

## Changes

- **`templates/repo/diff/compare.tmpl`**: Only render the grey “nothing
to compare” segment when `CompareInfo.CompareBase` is set.

<img width="1962" height="564"
src="https://github.com/user-attachments/assets/adc3b4a0-6f03-45da-b297-e15e5ad0aa79"
/>

---

Backport of https://github.com/go-gitea/gitea/pull/37651

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
---
 templates/repo/diff/compare.tmpl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/templates/repo/diff/compare.tmpl b/templates/repo/diff/compare.tmpl
index 9ed4b73174d..a7b7f38e342 100644
--- a/templates/repo/diff/compare.tmpl
+++ b/templates/repo/diff/compare.tmpl
@@ -211,7 +211,7 @@
 				</div>
 			{{end}}
 		{{else}}{{/* not singed-in or not for pull-request */}}
-			{{if not .CommitCount}}
+			{{if and (not .CommitCount) $.CompareInfo.MergeBase}}
 				<div class="ui segment">{{ctx.Locale.Tr "repo.commits.nothing_to_compare"}}</div>
 			{{end}}
 		{{end}}