Re: [RFC PATCH] userdiff: ship built-in driver config file

From: Junio C Hamano <gitster@pobox.com>
Date: Jun 19, 2019, 14:50 UTC
Message-ID: <xmqqfto5r5nr.fsf@gitster-ct.c.googlers.com>
In-Reply-To: <20190619034929.GA515@sigill.intra.peff.net>

Jeff King <peff@peff.net> writes:

> I think it _could_ actually just be part of the system /etc/gitconfig,
> though it is kind of big, and Git has a tendency to parse the config
> more than necessary. I wonder if would add a noticeable slowdown.

Yeah, that was what I was wondering too when somebody made a casual mention of the "why do we want to pile these settings hardcoded in the code for each and every language?", which I think led to this patch. I was actually imagining that this would be totally outside the normal config mechanism (there is no strong reason to even share the syntax, but there is no need to come up with a different syntax, either), treated like other fixed data files (like *.mo files), and is read lazily only when diff driver needs to be instantiated.

I also agree with you that changing how multiply-defined variables are handled with the patch is a no-go, if we are going to share the parser.

Thanks for a patch and a review.