Re: The transfer.hideRefs of the upload-pack process does not work properly

[Taylor Blau <me@ttaylorr.com>]

On Tue, Mar 04, 2025 at 12:38:50PM +0100, Patrick Steinhardt wrote:
> On Tue, Mar 04, 2025 at 02:51:46AM -0500, Jeff King wrote:
> > On Tue, Mar 04, 2025 at 02:51:14AM -0500, Jeff King wrote:
> >
> > > From your reproduction, it looks like the issue is that for loose refs,
> > > asking for_each_ref() to exclude "refs/heads/foo" will not yield
> > > "refs/heads/foo/bar", but will yield "refs/heads/foo-bar".
> > >
> > > And that was true for packed-refs, too, before 59c35fac54
> > > (refs/packed-backend.c: implement jump lists to avoid excluded
> > > pattern(s), 2023-07-10). After that, packed-refs exclude both.
> >
> > Oh, and of course it would be interesting to know how reftables behave
> > here, too, as I think they recently learned about exclusions.
>
> Well, we have tests that explicitly verify that prefixes cause us to
> exclude such refs in t1419, "overlapping exclude regions". So the
> reftable backend is bug-compatible :)
>
> Guess we'll need something similar to the following:
>
> diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c
> index 7e90e13f745..45462f2ce6d 100644
> --- a/refs/reftable-backend.c
> +++ b/refs/reftable-backend.c
> @@ -594,6 +594,16 @@ static int should_exclude_current_ref(struct reftable_ref_iterator *iter)
>  		if (cmp < 0)
>  			return 0;
>
> +		/*
> +		 * The exclude pattern needs to either match exactly, or, if it
> +		 * is a prefix of the given reference, it must be a containing
> +		 * directory.
> +		 */
> +		if (iter->ref.refname[iter->exclude_patterns_strlen] &&
> +		    pattern[iter->exclude_patterns_strlen - 1] != '/' &&
> +		    iter->ref.refname[iter->exclude_patterns_strlen] != '/')
> +			return 0;
> +
>  		/*
>  		 * The reference shares a prefix with the exclude pattern and
>  		 * shall thus be omitted. We skip all references that match the

Ah, makes sense. Thanks, both, for looking a little deeper. I can work
on a fix shortly...

Thanks,
Taylor