[PATCH] match_push_refs(): nobody sets src->peer_ref anymore

[PATCH] match_push_refs(): nobody sets src->peer_ref anymore

[Junio C Hamano]

In ancient times, we used to disallow the same source ref to be
pushed to more than one places, e.g. "git push there master:master
master:naster" was disallowed.  We later lifted this restriction
with db27ee63929f (send-pack: allow the same source to be pushed
more than once., 2005-08-06) and there no longer is anybody that
sets peer_ref for the source side of the ref list in the push
codepath since then.

Remove one leftover no-op in a loop that iterates over the source
side of ref list (i.e. our local ref) to see if it can/should be
sent to a matching destination ref while skipping ones that is
marked with peer_ref (which will never exist, so we do not skip
anything).

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 remote.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/remote.c b/remote.c
index e53a6eb..bac2b02 100644
--- a/remote.c
+++ b/remote.c
@@ -1227,9 +1227,6 @@ int match_push_refs(struct ref *src, struct ref **dst,
 		const struct refspec *pat = NULL;
 		char *dst_name;
 
-		if (ref->peer_ref)
-			continue;
-
 		dst_name = get_ref_match(rs, nr_refspec, ref, send_mirror, FROM_SRC, &pat);
 		if (!dst_name)
 			continue;
-- 
1.8.2-rc2-182-g857a7fa

Re: [PATCH] match_push_refs(): nobody sets src->peer_ref anymore

[Jeff King]

On Mon, Mar 04, 2013 at 02:36:33PM -0800, Junio C Hamano wrote:

> In ancient times, we used to disallow the same source ref to be
> pushed to more than one places, e.g. "git push there master:master
> master:naster" was disallowed.  We later lifted this restriction
> with db27ee63929f (send-pack: allow the same source to be pushed
> more than once., 2005-08-06) and there no longer is anybody that
> sets peer_ref for the source side of the ref list in the push
> codepath since then.
> 
> Remove one leftover no-op in a loop that iterates over the source
> side of ref list (i.e. our local ref) to see if it can/should be
> sent to a matching destination ref while skipping ones that is
> marked with peer_ref (which will never exist, so we do not skip
> anything).
> 
> Signed-off-by: Junio C Hamano <gitster@pobox.com>

This looks good to me. I was curious how difficult it would be to verify
the "no longer is anybody that sets peer_ref" claim. It's actually quite
easy. All of the call-sites just feed the result of get_local_heads(),
which is easy to verify does not ever set peer_ref. Looking at the
current code, I think you could even drop the "src" parameter and just
have match_push_refs call get_local_heads() itself, though that does
feel like a step backwards in terms of function generality.

As an aside, I have always found the embedded "next" and "peer_ref"
pointers in "struct ref" to be hacky. They are not properties of the ref
at all, and the "refs to fetch" list would be more logically represented
as a list of pairs of refs (and then I would not have to ever remember
whether the peer is the local or remote ref in a given case). Probably
not worth worrying about at this point, though, as the code fallout
would be significant for little gain.

-Peff