Subject: [PATCH] stash: strip "refs/heads/" with skip_prefix

From: Glen Choo <[email-masked]>
Date: Mon, 24 Jan 2022 12:53:42 -0800

When generating a message for a stash, "git stash" only records the
part of the branch name to the right of the last "/". e.g. if HEAD is at
"foo/bar/baz", "git stash" generates a message prefixed with "WIP on
baz:" instead of "WIP on foo/bar/baz:".

Fix this by using skip_prefix() to skip "refs/heads/" instead of looking
for the last instance of "/".

Reported-by: Kraymer <[email-masked]>
Reported-by: Daniel Hahler <[email-masked]>
Helped-by: Jeff King <[email-masked]>
Signed-off-by: Glen Choo <[email-masked]>
---
I prepared this fix before checking the mailing list for any bug
reports; turns out that there are at least two existing reports.

My fix happens to be exactly the same as what Peff suggested, with the
additional test that he asked for.

 builtin/stash.c  |  2 +-
 t/t3903-stash.sh | 11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/builtin/stash.c b/builtin/stash.c
index 1ef2017c59..01f072a2fb 100644
--- a/builtin/stash.c
+++ b/builtin/stash.c
@@ -1332,7 +1332,7 @@ static int do_create_stash(const struct pathspec *ps, struct strbuf *stash_msg_b
 
 	branch_ref = resolve_ref_unsafe("HEAD", 0, NULL, &flags);
 	if (flags & REF_ISSYMREF)
-		branch_name = strrchr(branch_ref, '/') + 1;
+		skip_prefix(branch_ref, "refs/heads/", &branch_name);
 	head_short_sha1 = find_unique_abbrev(&head_commit->object.oid,
 					     DEFAULT_ABBREV);
 	strbuf_addf(&msg, "%s: %s ", branch_name, head_short_sha1);
diff --git a/t/t3903-stash.sh b/t/t3903-stash.sh
index 686747e55a..bf83fb940e 100755
--- a/t/t3903-stash.sh
+++ b/t/t3903-stash.sh
@@ -1042,6 +1042,17 @@ test_expect_success 'create stores correct message' '
 	test_cmp expect actual
 '
 
+test_expect_success 'create when branch name has /' '
+	test_when_finished "git checkout main" &&
+	git checkout -b some/topic &&
+	>foo &&
+	git add foo &&
+	STASH_ID=$(git stash create "create test message") &&
+	echo "On some/topic: create test message" >expect &&
+	git show --pretty=%s -s ${STASH_ID} >actual &&
+	test_cmp expect actual
+'
+
 test_expect_success 'create with multiple arguments for the message' '
 	>foo &&
 	git add foo &&

base-commit: 89bece5c8c96f0b962cfc89e63f82d603fd60bed
-- 
2.33.GIT