Re: amend warnings with no changes staged

From: Junio C Hamano <gitster@pobox.com>
Date: Aug 6, 2019, 19:11 UTC
Message-ID: <xmqqblx2jeh2.fsf@gitster-ct.c.googlers.com>
In-Reply-To: <20190806041911.GA9243@sigill.intra.peff.net>

Jeff King <peff@peff.net> writes:

Show 11 quoted lines

>   git commit -m 'buggy commit'
>   echo fix >>file.c
>   git commit --amend ;# oops, should have been "-a"
>   git push
>
> But perhaps that gets to the heart of the matter. Could we perhaps be
> providing a more detailed summary of what happened for an --amend? I.e.,
> to summarize _both_ sets of changes (and if one set is empty, say so)?
> ...
> judgement about whether it's an error, since it may well be that you
> were simply rewording the commit message).

Perhaps "git range-diff HEAD@{1}...HEAD" being an empty is a sign that either the user intentionally or accidentally did not do anything other than "touch"ing the commit.

"git commit --amend --[no-]range-diff" that shows what you changed with the amending may be an interesting possibility; I am not yet ready to seriously encourage anybody to explore it, though, because "git diff HEAD@{1}" is much easier to see what code got changed, but one (and probably only) downside is that it does not cover the change in the log message.