Re: prepare-commit-msg hook no longer run for cherry-pick?

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Tue, Jan 9, 2018 at 6:24 PM, Junio C Hamano <gitster@pobox.com> wrote:
>
> Dmitry Torokhov <dmitry.torokhov@gmail.com> writes:
>
> >> I had prepare-commit-msg hook that would scrub "Patchwork-ID: NNNN" tags
> >> form commit messages and would update input mailing list patchwork to
> >> mark corresponding patches as "accepted" when I cherry pick form
> >> WIP/review queue into branches that I publish, but that recently stopped
> >> working if I do a simple cherry-pick.
> >
> > This seems like a regression, at least for my use case. Unfortunately
> > my mail seems to get lost in the mailing list noise...
>
> Possibly.  Can you bisect to see which commit broke things for you?
> That would allow people who know what they themselves broke better
> than I do to take a look ;-)

Right, so it looks like the master works well, it is next(?) branch
that is troublesome (apparently we pack experimental internally?).

I bisected it down to:

commit 356ee4659bb551cd9464b317d691827276752c2d (refs/bisect/bad)
Author: Phillip Wood <phillip.wood@dunelm.org.uk>
Date:   Fri Nov 24 11:07:57 2017 +0000

   sequencer: try to commit without forking 'git commit'

   If the commit message does not need to be edited then create the
   commit without forking 'git commit'. Taking the best time of ten runs
   with a warm cache this reduces the time taken to cherry-pick 10
   commits by 27% (from 282ms to 204ms), and the time taken by 'git
   rebase --continue' to pick 10 commits by 45% (from 386ms to 212ms) on
   my computer running linux. Some of greater saving for rebase is
   because it no longer wastes time creating the commit summary just to
   throw it away.

   The code to create the commit is based on builtin/commit.c. It is
   simplified as it doesn't have to deal with merges and modified so that
   it does not die but returns an error to make sure the sequencer exits
   cleanly, as it would when forking 'git commit'

   Even when not forking 'git commit' the commit message is written to a
   file and CHERRY_PICK_HEAD is created unnecessarily. This could be
   eliminated in future. I hacked up a version that does not write these
   files and just passed an strbuf (with the wrong message for fixup and
   squash commands) to do_commit() but I couldn't measure any significant
   time difference when running cherry-pick or rebase. I think
   eliminating the writes properly for rebase would require a bit of
   effort as the code would need to be restructured.

   Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
   Signed-off-by: Junio C Hamano <gitster@pobox.com>

With this commit the hook is not being run unless I specify '-e' flag
to cherry-pick.

Thanks.

-- 
Dmitry