From: Felipe Contreras <felipe.contreras@gmail.com>
To: Sergey Organov <sorganov@gmail.com>, Junio C Hamano <gitster@pobox.com>
Cc: Matthieu Moy <Matthieu.Moy@univ-lyon1.fr>,
Felipe Contreras <felipe.contreras@gmail.com>,
"git@vger.kernel.org" <git@vger.kernel.org>
Subject: Re: Can we clarify the purpose of `git diff -s`?
Date: Fri, 12 May 2023 13:47:38 -0600 [thread overview]
Message-ID: <645e97da9d11e_21989f2945d@chronos.notmuch> (raw)
In-Reply-To: <87h6shif6q.fsf@osv.gnss.ru>
Sergey Organov wrote:
> Junio C Hamano <gitster@pobox.com> writes:
>
> > Matthieu Moy <Matthieu.Moy@univ-lyon1.fr> writes:
> >
> >> https://public-inbox.org/git/51E3DC47.70107@googlemail.com/
> >>
> >> Essentially, Stefan Beller was using 'git show --format="%ad"' and
> >> expecting it to show only the author date, and for merge commits it
> >> also showed the patch (--cc). I suggested -s and noticed that the
> >> option wasn't easily discoverable, hence the patch series to better
> >> document it and add --no-patch as a synonym.
> >>
> >> Probably I did not get all the subtleties of the different kinds of
> >> outputs. I guess I considered the output of diff to be the one
> >> specified by --format plus the patch (not considering --raw, --stat &
> >> friends), hence "get only the output specified by --format" and
> >> "disable the patch" were synonym to me.
>
> So --no-patch, if it were made to disable only --patch from the
> beginning, would still serve the purpose of solving of the original
> problem, right? Please notice that --cc produces no output without
> --patch. Thus, making --no-patch a synonym for -s was a mistake in the
> first place that leaked through review process at that time, and
>
> git show --format="%ad" --no-patch
>
> will still work the same way even if we fix --no-patch to disable
> --patch only.
Indeed.
> > Thanks for double checking. It matches my recollection that we (you
> > the author and other reviewers as well) added "--no-patch" back then
> > to mean "no output from diff machinery, exactly the same as '-s' but
> > use a name that is more discoverable".
> >
> >> Looking more closely, it's
> >> rather clear to me they are not, and that
> >>
> >> git show --raw --patch --no-patch
> >>
> >> should be equivalent to
> >>
> >> git show --raw
> >
> > Yeah. If this were 10 years ago and we were designing from scratch,
> > the "no output from diff machinery, more discoverable alias for
> > '-s'" would have been "--silent" or "--squelch" and we would made
> > any "--no-<format>" to defeat only "--<format>".
> >
> > It is a different matter if we can safely change what "--no-patch"
> > means _now_. Given that "--no-patch" was introduced for the
> > explicit purpose of giving "-s" a name that is easier to remember,
> > and given that in the 10 years since we did so, we may have acquired
> > at least a few more end users of Git than we used to have, hopefully
> > your change have helped them discover and learn to use "--no-patch"
> > to defeat any "--<format>" they gave earlier as initial options in
> > their script, which will be broken and need to be updated to use a
> > much less discoverable "-s".
>
> Fortunately, whoever used --no-patch are very unlikely to actually rely
> on it being a synonym for "-s", as it was always enough for them that
> --no-patch disables --patch, that will still hold after the fix.
That's right.
And let's be realistic for a moment: nobody actually does `git diff-files
--raw`, as that's essentially the same as `cat /dev/null`: a no-op.
The reason `--no-patch` was added was to silenced the diff output of commands
that show a diff *in addition* to something else by default, like `git show`,
and `git show --no-patch` will keep working fine.
Why would anybody do `git show --raw --no-patch` when they can do
`git show --no-patch`?
Yet once again we are doing premature defense for a set of users that probably
don't even exist.
> Finally, this safety concern is even less attractive provided recent
> "-s" fix changed behavior more aggressively yet gets no such resistance.
Exactly.
---
And this is yet another example of why git's UI is stuck and cannot (and
probably will never) be fixed.
Cheers.
--
Felipe Contreras
next prev parent reply other threads:[~2023-05-12 19:47 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-05-11 3:14 Can we clarify the purpose of `git diff -s`? Felipe Contreras
2023-05-11 11:59 ` Sergey Organov
2023-05-11 16:26 ` Junio C Hamano
2023-05-11 17:37 ` Junio C Hamano
2023-05-11 18:04 ` Sergey Organov
2023-05-11 18:27 ` Junio C Hamano
2023-05-11 18:36 ` Felipe Contreras
2023-05-11 18:17 ` Felipe Contreras
2023-05-11 17:41 ` Felipe Contreras
2023-05-11 18:31 ` Sergey Organov
2023-05-11 19:10 ` Felipe Contreras
2023-05-11 19:32 ` Sergey Organov
2023-05-11 19:54 ` Felipe Contreras
2023-05-11 20:24 ` Sergey Organov
2023-05-11 20:59 ` Felipe Contreras
2023-05-11 22:49 ` Sergey Organov
2023-05-11 23:28 ` Felipe Contreras
2023-05-12 8:40 ` Sergey Organov
2023-05-12 19:19 ` Felipe Contreras
[not found] ` <5bb24e0208dd4a8ca5f6697d578f3ae0@SAMBXP02.univ-lyon1.fr>
2023-05-12 8:15 ` Matthieu Moy
2023-05-12 17:03 ` Junio C Hamano
2023-05-12 18:21 ` Sergey Organov
2023-05-12 19:21 ` Junio C Hamano
2023-05-12 19:34 ` Junio C Hamano
2023-05-12 20:28 ` Felipe Contreras
2023-05-12 20:47 ` Junio C Hamano
2023-05-12 21:01 ` Felipe Contreras
2023-05-12 21:47 ` Junio C Hamano
2023-05-12 21:48 ` Junio C Hamano
2023-05-12 23:21 ` Felipe Contreras
2023-05-12 21:41 ` Sergey Organov
2023-05-12 22:17 ` Junio C Hamano
2023-05-12 22:47 ` Sergey Organov
2023-05-12 23:07 ` Felipe Contreras
2023-05-13 14:58 ` Philip Oakley
2023-05-13 17:45 ` Sergey Organov
2023-05-12 19:47 ` Felipe Contreras [this message]
2023-05-12 19:34 ` Felipe Contreras
2023-05-12 19:17 ` Felipe Contreras
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