From: Junio C Hamano <gitster@pobox.com>
Date: Fri, 29 Aug 2025 16:44:37 +0000 (-0700)
Subject: Merge branch 'jk/no-clobber-dangling-symref-with-fetch'
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=fea9d18c534a445ef6e488d8ee711fa92fa0e6bd;p=thirdparty%2Fgit.git

Merge branch 'jk/no-clobber-dangling-symref-with-fetch'

"git fetch" can clobber a symref that is dangling when the
remote-tracking HEAD is set to auto update, which has been
corrected.

* jk/no-clobber-dangling-symref-with-fetch:
  refs: do not clobber dangling symrefs
  t5510: prefer "git -C" to subshell for followRemoteHEAD tests
  t5510: stop changing top-level working directory
  t5510: make confusing config cleanup more explicit
---

fea9d18c534a445ef6e488d8ee711fa92fa0e6bd
diff --cc t/t1400-update-ref.sh
index 96648a6e5d,29b31e3b9b..b7415ec9d5
--- a/t/t1400-update-ref.sh
+++ b/t/t1400-update-ref.sh
@@@ -2349,23 -2310,25 +2349,44 @@@ test_expect_success 'update-ref should 
  	test_cmp expect actual
  '
  
 +test_expect_success REFFILES 'empty directories are pruned when aborting a transaction' '
 +	test_path_is_missing .git/refs/heads/nested &&
 +	git update-ref --stdin <<-EOF &&
 +	create refs/heads/nested/something HEAD
 +	prepare
 +	abort
 +	EOF
 +	test_path_is_missing .git/refs/heads/nested
 +'
 +
 +test_expect_success REFFILES 'empty directories are pruned when not committing' '
 +	test_path_is_missing .git/refs/heads/nested &&
 +	git update-ref --stdin <<-EOF &&
 +	create refs/heads/nested/something HEAD
 +	prepare
 +	EOF
 +	test_path_is_missing .git/refs/heads/nested
 +'
 +
+ test_expect_success 'dangling symref not overwritten by creation' '
+ 	test_when_finished "git update-ref -d refs/heads/dangling" &&
+ 	git symbolic-ref refs/heads/dangling refs/heads/does-not-exist &&
+ 	test_must_fail git update-ref --no-deref --stdin 2>err <<-\EOF &&
+ 	create refs/heads/dangling HEAD
+ 	EOF
+ 	test_grep "cannot lock.*dangling symref already exists" err &&
+ 	test_must_fail git rev-parse --verify refs/heads/dangling &&
+ 	test_must_fail git rev-parse --verify refs/heads/does-not-exist
+ '
+ 
+ test_expect_success 'dangling symref overwritten without old oid' '
+ 	test_when_finished "git update-ref -d refs/heads/dangling" &&
+ 	git symbolic-ref refs/heads/dangling refs/heads/does-not-exist &&
+ 	git update-ref --no-deref --stdin <<-\EOF &&
+ 	update refs/heads/dangling HEAD
+ 	EOF
+ 	git rev-parse --verify refs/heads/dangling &&
+ 	test_must_fail git rev-parse --verify refs/heads/does-not-exist
+ '
+ 
  test_done