Git should work regardless where the working directory is located,
even at root. This patch fixes two places where it assumes working
directory always have parent directory.
In setup_git_directory_gently(), when Git goes up to root and finds
.git there, it happily sets worktree to "" instead of "/".
In prefix_path(), loosen the outside repo check a little bit. Usually
when a path XXX is inside worktree /foo, it must be either "/foo", or
"/foo/...". When worktree is simply "/", we can safely ignore the
check: we have a slash at the beginning already.
Not related to worktree, but also set gitdir correctly if a bare repo
is placed (insanely?) at root.
Thanks João Carlos Mendes Luís for pointing out this problem.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>