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

1 files changed, 21 insertions, 0 deletions

diff --git a/t/t1400-update-ref.sh b/t/t1400-update-ref.sh
index 96648a6e5d..b7415ec9d5 100755
--- a/t/t1400-update-ref.sh
+++ b/t/t1400-update-ref.sh
@@ -2368,4 +2368,25 @@ test_expect_success REFFILES 'empty directories are pruned when not committing'
 	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