branch tests: test for errno propagating on failing read
Add a test for "git branch" to cover the case where .git/refs is symlinked. To check availability, refs_verify_refname_available() will run refs_read_raw_ref() on each prefix, leading to a read() from .git/refs (which is a directory). It would probably be more robust to re-issue the lstat() as a normal stat(), in which case, we would fall back to the directory case, but for now let's just test for the existing behavior as-is. This test covers a regression in a commit that only ever made it to "next", see [1]. 1. http://lore.kernel.org/git/pull.1068.git.git.1629203489546.gitgitgadget@gmail.com Signed-off-by: Han-Wen Nienhuys <hanwen@google.com> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>