Re: [PATCH] remote: introduce config to set prefetch refs

From: Junio C Hamano <gitster@pobox.com>
Date: Sep 14, 2024, 20:11 UTC
Message-ID: <xmqqo74qro6f.fsf@gitster.g>
In-Reply-To: <CAG=Um+2e7kSL8wGFJcJtFAJt8AxyNwpemJNnxDNfsrm1SVVw1Q@mail.gmail.com>

Shubham Kanodia <shubham.kanodia10@gmail.com> writes:

Show 6 quoted lines

> If we're trying to determine if a pattern
> (remote.<remote>.prefetchref) is a subset of another or not
> (remote.<remote>.fetch) (to not accidentally expand the scope beyond
> `fetch`),
> we'd need a function that does that pattern-to-pattern. Are you aware
> of any existing functions that do so?

There is no such computation for this application. Such a computation might become needed if you wanted to complain that the user gave .prefetchref pattern that would never match what .fetch patterns would allow to pass. But there is no such need.

You will first get the advertised refs from the remote.

Existing logic filteres them down to what matches configured remote.$name.fetch variable. filter_prefetch_refspec() may further reduces the result by removing those whose .src side begins with "refs/tags/".

Now you only look at what survived the above existing filtering, and further narrow it down by picking only ones that match the prefetch condition. If the refspec that survived the filtering by the fetch refspec (and existing logic in filter_prefetch_refspec()) does not satisfy the prefetch condition, it won't be prefetched.

Since you are using .prefetch ONLY TO narrow the result down, by definition, you are not adding anything what .fetch configuration would not have fetched.