When fetching a ref from a remote server, the ref file can contain a comment, like: The file FETCH_HEAD: ecc2505c5d373f8384477cc4d831bbd9323d061c 'refs/my/stuff' of git://my.git/my/repo.git Because this comment is prefixed with two tabs, it breaks the value.split() call in SymbolicReference._get_ref_info().