Re: [PATCH 4/4] commit: don't lazy-fetch commits

From: Junio C Hamano <gitster@pobox.com>
Date: Nov 30, 2022, 23:56 UTC
Message-ID: <xmqq5yewuhc0.fsf@gitster.g>
In-Reply-To: <6af8dcebd14d803fc8d2a01fbcc7f42ff380719d.1669839849.git.jonathantanmy@google.com>

Jonathan Tan <jonathantanmy@google.com> writes:

Show 11 quoted lines

> When parsing commits, fail fast when the commit is missing or
> corrupt, instead of attempting to fetch them. This is done by
> inlining repo_read_object_file() and setting the flag that
> prevents fetching.
>
> This is motivated by a situation in which through a bug (not
> necessarily through Git), there was corruption in the object store
> of a partial clone. In this particular case, the problem was
> exposed when "git gc" tried to expire reflogs, which calls
> repo_parse_commit(), which triggers fetches of the missing
> commits.

The assumption is that there will never be a filtering mode that says "give us tags and we will lazy-fetch everything reachable from it when we need it", with which the "solution" will break down, I think, and I would say it is probably good enough.