Re: diff-index --cc no longer permitted, gitk is now broken (slightly)

From: Sergey Organov <sorganov@gmail.com>
To: Philip Oakley <philipoakley@iee.email>
Cc: Junio C Hamano <gitster@pobox.com>, Johannes Sixt <j6t@kdbg.org>,
	Jeff King <peff@peff.net>, Paul Mackerras <paulus@ozlabs.org>,
	Git Mailing List <git@vger.kernel.org>
Subject: Re: diff-index --cc no longer permitted, gitk is now broken (slightly)
Date: Sat, 18 Sep 2021 20:56:19 +0300	[thread overview]
Message-ID: <87mto99398.fsf@osv.gnss.ru> (raw)
In-Reply-To: <87ee9n5cob.fsf@osv.gnss.ru> (Sergey Organov's message of "Fri, 17 Sep 2021 20:34:12 +0300")

Sergey Organov <sorganov@gmail.com> writes:

> Philip Oakley <philipoakley@iee.email> writes:
>
>> On 17/09/2021 08:08, Sergey Organov wrote:
>>> Junio C Hamano <gitster@pobox.com> writes:
>>>
>>>> Sergey Organov <sorganov@gmail.com> writes:
>>>>
>>>>> I'm not sure I follow. What "show -p" has to do with "diff-index --cc"?
>>>>>
>>>>> My only point here is that usage of *--cc* in *diff-index* is entirely
>>>>> undocumneted, and that needs to be somehow resolved.
>>>> It was a response to your "historical status quo that is a problem."
>>>> I do not think there is any problem with "diff-index --cc" (except
>>>> for it wants a better documentation---but that we already agree) but
>>> Ah, now I see, but it's exactly lack of documentation (and tests) that I
>>> was referring to as the "problem of the historical status quo" on the
>>> Git side, so I was somewhat confused by your original response.
>>>
>>> Also, it's still unclear, even if not very essential, what exactly that
>>> "status quo" is when seen from the point of view of gitk. Does gitk
>>> actually utilize *particular output* of "diff-index --cc" for better, or
>>> gitk would be just as happy if it were synonym for "diff-index -p", or
>>> even if it'd be just as happy if --cc were silently consumed by
>>> diff-index?
>>
>> Did Johannes Sixt's earlier answer
>> https://lore.kernel.org/git/cbd0d173-ef17-576b-ab7a-465d42c82265@kdbg.org/
>> help clarify the choices?
>
> Sorry, no. I did read that carefully when it has been posted. Further
> explanations by Johannes also only tell that gitk expects --cc to be
> accepted by diff-index as it likes to treat multiple commands
> universally, but don't specify what output git expects from --cc when it
> passes it exactly to diff-index. Maybe it just shows the output and have
> no other expectations, dunno.

And, even more importantly, if gitk uses "git diff-index --cc" for its
specific output, is there another, documented way to achieve the same
goal?

Thanks,
-- Sergey Organov