From bd52d9a0583a2d12f584fdf6b47d2c2f51c0d791 Mon Sep 17 00:00:00 2001 From: Taylor Blau Date: Fri, 7 Mar 2025 18:27:03 -0500 Subject: [PATCH] fetch: fix following tags when fetching specific OID In 3f763ddf28 (fetch: set remote/HEAD if it does not exist, 2024-11-22), unconditionally adds "HEAD" to the list of ref prefixes we send to the server. This breaks a core assumption that the list of prefixes we send to the server is complete. We must either send all prefixes we care about, or none at all (in the latter case the server then advertises everything). The tag following code is careful to only add "refs/tags/" to the list of prefixes if there are already entries in the prefix list. But because the new code from 3f763ddf28 runs after the tag code, and because it unconditionally adds to the prefix list, we may end up with a prefix list that _should_ have "refs/tags/" in it, but doesn't. When that is the case, the server does not advertise any tags, and our auto-following breaks because we never learned about any tags in the first place. Fix this by only adding "HEAD" to the ref prefixes when we know that we are already limiting the advertisement. In either case we'll learn about HEAD (either through the limited advertisement, or implicitly through a full advertisement). Reported-by: Igor Todorovski Co-authored-by: Jeff King Signed-off-by: Jeff King Signed-off-by: Taylor Blau Signed-off-by: Junio C Hamano --- builtin/fetch.c | 4 +++- t/t5503-tagfollow.sh | 14 ++++++++++++++ 2 files changed, 17 insertions(+), 1 deletion(-) diff --git a/builtin/fetch.c b/builtin/fetch.c index fe2b26c74a..a06d130501 100644 --- a/builtin/fetch.c +++ b/builtin/fetch.c @@ -1777,7 +1777,9 @@ static int do_fetch(struct transport *transport, if (uses_remote_tracking(transport, rs)) { must_list_refs = 1; - strvec_push(&transport_ls_refs_options.ref_prefixes, "HEAD"); + if (transport_ls_refs_options.ref_prefixes.nr) + strvec_push(&transport_ls_refs_options.ref_prefixes, + "HEAD"); } if (must_list_refs) { diff --git a/t/t5503-tagfollow.sh b/t/t5503-tagfollow.sh index 195fc64dd4..845ca43ea0 100755 --- a/t/t5503-tagfollow.sh +++ b/t/t5503-tagfollow.sh @@ -160,4 +160,18 @@ test_expect_success 'new clone fetch main and tags' ' test_cmp expect actual ' +test_expect_success 'fetch specific OID with tag following' ' + git init --bare clone3.git && + ( + cd clone3.git && + git remote add origin .. && + git fetch origin $B:refs/heads/main && + + git -C .. for-each-ref >expect && + git for-each-ref >actual && + + test_cmp expect actual + ) +' + test_done