Re: [PATCH v5 17/23] userdiff.c: remove implicit dependency on the_index

From: Junio C Hamano <gitster@pobox.com>
Date: Oct 10, 2018, 22:14 UTC
Message-ID: <xmqq7eipla9k.fsf@gitster-ct.c.googlers.com>
In-Reply-To: <20181010145116.GA11772@sigill.intra.peff.net>

Jeff King <peff@peff.net> writes:

Show 6 quoted lines

> I get why you're doing it: your topic here only cares about removing
> index dependencies, so you did the minimal thing to move that forward.
>
> But if you think about what this function is doing, it is quite clearly
> dependent on the whole repository, since the userdiff config we're
> looking up may come from repo config.

In the case of userdiff that is pretty much limited to read-only operation, I fully agree, but in more general cases, we would need to pass both the repository and an in-core index separately, I would say. Imagine doing a partial commit, where we construct a separate istate that is not the "repo's index" and use that to write out a tree object to be wrapped in a new commit, and update the current branch ref.