Re: [PATCH v3 12/16] refs/packed-backend.c: ignore complicated hidden refs rules

From: Junio C Hamano <gitster@pobox.com>
Date: Jun 14, 2023, 00:40 UTC
Message-ID: <xmqqo7li27ww.fsf@gitster.g>
In-Reply-To: <ca006b2c3f3474cdf7cfebbdb8575059e036d9cc.1686134440.git.me@ttaylorr.com>

Taylor Blau <me@ttaylorr.com> writes:

> In subsequent commits, we'll teach `receive-pack` and `upload-pack` to
> use the new skip-list feature in the packed-refs iterator by ignoring

"skip" -> "jump".

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> references which are mentioned via its respective hideRefs lists.
>
> However, the packed-ref skip lists cannot handle un-hiding rules (that
> begin with '!'), or namespace comparisons (that begin with '^'). Detect
> and avoid these cases by falling back to the normal enumeration without
> a skip list when such patterns exist.

Show 6 quoted lines

> +		 * We also can't feed any excludes from hidden refs
> +		 * config sections, since later rules may override
> +		 * previous ones. For example, with rules "refs/foo" and
> +		 * "!refs/foo/bar", we should show "refs/foo/bar" (and
> +		 * everything underneath it), but the earlier exclusion
> +		 * would cause us to skip all of "refs/foo".

Good observation. The presence of !refs/foo/bar in hide list forbids us from adding refs/foo to the jump list, and it is the simplest to disable the whole jump list business when we have such a feature in use.

Makes sense.  Thanks.