Re: can I remove or move a tag in a remote repository?

Jim Meyering [off-list ref] writes:

Here's the problem:
When I try to push the new tags, git-push fails:

  $ git-push -f --tags ssh+git://git.sv.gnu.org/srv/git/coreutils master:refs/heads/master
  updating 'refs/tags/cvs-head'
    from 2fd3fd29a8b40be695bc2327c8cd3bd33e521100
    to   db18f53ffb221e9957124d8af81c11a7e350ac3b
  ...
  Total 1, written 1 (delta 0), reused 0 (delta 0)
  Unpacking 1 objects
  error: denying non-fast forward; you should pull first

I get the same error also when using --force.

I think this is due to overeager receive.denyNonFastForwards
configuration setting at the repository you are pushing into.

I _think_ what receive-pack does in this case is totally wrong.
It should either:

 (1) deny overwriting existing tags -- tags are meant to be
     immutable so it should not allow them to be "updated"
     regardless of fast-forwardness, or

 (2) allow overwriting things under refs/tags/ without any
     fast-forward checking.  After all, a tag could point at a
     tree or a blob, and there is no fast-forwardness among
     trees.

The client side check in "git fetch" takes the latter viewpoint,
and I think we should be consistent with it.

Johannes, what do you think?  Does the following patch look sane
to you?

---

diff --git a/receive-pack.c b/receive-pack.c
index 1a141dc..6c3de47 100644
--- a/receive-pack.c
+++ b/receive-pack.c

@@ -120,7 +120,7 @@ static int update(struct command *cmd)
 			     "but I can't find it!", new_hex);
 	}
 	if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
-	    !is_null_sha1(old_sha1)) {
+	    !is_null_sha1(old_sha1) && !strncmp(name, "refs/heads/", 11)) {
 		struct commit *old_commit, *new_commit;
 		struct commit_list *bases, *ent;