Re: [PATCH 0/1] send-pack: set core.warnAmbiguousRefs=false

On Tue, Nov 06, 2018 at 02:44:42PM -0500, Jeff King wrote:

quoted

The fix for this is simple: set core.warnAmbiguousRefs to false for this
specific call of git pack-objects coming from git send-pack. We don't want
to default it to false for all calls to git pack-objects, as it is valid to
pass ref names instead of object ids. This helps regain these seconds during
a push.

I don't think you actually care about the ambiguity check between refs
here; you just care about avoiding the ref check when we've seen (and
are mostly expecting) a 40-hex sha1. We have a more specific flag for
that: warn_on_object_refname_ambiguity.

And I think it would be OK to enable that all the time for pack-objects,
which is plumbing that does typically expect object names. See prior art
in 25fba78d36 (cat-file: disable object/refname ambiguity check for
batch mode, 2013-07-12) and 4c30d50402 (rev-list: disable object/refname
ambiguity check with --stdin, 2014-03-12).

I'd probably do it here:

diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index e50c6cd1ff..d370638a5d 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c

@@ -3104,6 +3104,7 @@ static void get_object_list(int ac, const char **av)
 	struct rev_info revs;
 	char line[1000];
 	int flags = 0;
+	int save_warning;
 
 	repo_init_revisions(the_repository, &revs, NULL);
 	save_commit_buffer = 0;

@@ -3112,6 +3113,9 @@ static void get_object_list(int ac, const char **av)
 	/* make sure shallows are read */
 	is_repository_shallow(the_repository);
 
+	save_warning = warn_on_object_refname_ambiguity;
+	warn_on_object_refname_ambiguity = 0;
+
 	while (fgets(line, sizeof(line), stdin) != NULL) {
 		int len = strlen(line);
 		if (len && line[len - 1] == '\n')

@@ -3138,6 +3142,8 @@ static void get_object_list(int ac, const char **av)
 			die(_("bad revision '%s'"), line);
 	}
 
+	warn_on_object_refname_ambiguity = save_warning;
+
 	if (use_bitmap_index && !get_object_list_from_bitmap(&revs))
 		return;
 

But I'll leave it to you to wrap that up in a patch, since you probably
should re-check your timings (which it would be interesting to include
in the commit message, if you have reproducible timings).

-Peff