Re: [PATCH 2/2] Allow passing pipes for input pipes to diff --no-index

From: Junio C Hamano <gitster@pobox.com>
Date: Sep 21, 2020, 20:14 UTC
Message-ID: <xmqq1riuga5m.fsf@gitster.c.googlers.com>
In-Reply-To: <20200921193120.GB2399334@coredump.intra.peff.net>

Jeff King <peff@peff.net> writes:

Show 6 quoted lines

> We'd sometimes wait several versions before that last step to give
> people time to adjust scripts, etc. But in this case, I suspect it would
> be OK to just flip it immediately. We don't consider "git diff" itself
> part of the stable plumbing, and the --no-index part of it I would
> consider even less stable. And AFAICT most people consider the current
> behavior a bug because it doesn't behave like other diff tools.

The "git diff" proper gets no filenames from the command line and the above strictly applies only to the no-index mode, with or without the explicit "--no-index" option.

It was a way to give Git niceties like colored diffs, renames, etc. to non-Git managed two sets of paths, and the primary reason why we have it as a mode of "git diff" is because we chose not to bother with interacting with upstream maintainers of "diff". In an ideal world, "GNU diff" and others would have learned things like renames, word diffs, etc., instead of "git diff" adding "--no-index" mode.

And that makes me agree that users expect "git diff --no-index" to behave like other people's diff and that is more important than behaving like "git diff" for that mode.