Re: [PATCH 1/4] rebase -i: add ack action

From: Junio C Hamano <gitster@pobox.com>
To: Matthieu Moy <Matthieu.Moy@grenoble-inp.fr>
Cc: "Michael S. Tsirkin" <mst@redhat.com>,
	Johannes Schindelin <Johannes.Schindelin@gmx.de>,
	git@vger.kernel.org, bafain@gmail.com, sunshine@sunshineco.com
Subject: Re: [PATCH 1/4] rebase -i: add ack action
Date: Tue, 12 Apr 2016 09:07:30 -0700	[thread overview]
Message-ID: <xmqqd1pustdp.fsf@gitster.mtv.corp.google.com> (raw)
In-Reply-To: <vpqr3ebnc9w.fsf@anie.imag.fr> (Matthieu Moy's message of "Mon, 11 Apr 2016 22:03:39 +0200")

Matthieu Moy <Matthieu.Moy@grenoble-inp.fr> writes:

> "Michael S. Tsirkin" <mst@redhat.com> writes:
>
>> Interesting. An empty commit would be rather easy to create on any
>> branch, not just the current one, using git-commit-tree.
>
> This "modify a branch without checking-it out" makes me think of "git
> notes". It may make sense to teach "git rebase -i" to look for notes in
> rebased commits and append them to the commit message when applying.
> Just an idea, not necessarily a good one ;-).

Yeah that may actually fly well, as a note is designed to attach to
an exact commit, not to a branch, so that feels more natural.

As to the "use commit-tree", well, personally I am not interested in
a solution that can work well in my workflow ONLY if I further script
it.  That's half-solution and unless that half is done very well,
I'd rather do a full solution better.

	Note: this is a continuation of "I personally would not use
	it, even though other people might" discussion.

I was also wondering if I should just script around filter-branch,
if all I am futzing with is the data in the trailer block, doing the
munging of the trailer block with interpret-trailers, naturally.

In any case, a recent occasion that I had to do something related to
this topic may illustrate the boundary of requirements:

    Two developers, Michael and David, are involved.  David sends a
    24-patch series, some of which were written by Michael and
    others by David.  The in-body "From:" lines are set right and
    the resulting patches record authorship correctly.

    Michael reminds David that patches authored by Michael still
    need to be signed-off by David.  David sends a single message
    "those by Michael in this series are signed off by me".

    Michael also says that he reviewed all patches authored by
    David, i.e. "Add Acked-by Michael to all patches in this series
    authored by David".

Now this is an extreme case where a simple "OK I received an
e-mailed Ack, so I can rely on the subject line matching to mark it
to be squashed" approach will never work (i.e. if we were automating
it I'd expect that the script in DSL to the automation machinery to
take at last as many (conceptual) bits as the above problem
description).