Re: refs/notes/amlog problems, was Re: [PATCH v3 01/20] linear-assignment: a function to solve least-cost assignment problems

From: Junio C Hamano <gitster@pobox.com>
Date: Jul 19, 2018, 17:06 UTC
Message-ID: <xmqqa7qngnon.fsf@gitster-ct.c.googlers.com>
In-Reply-To: <xmqq8t6gz8xz.fsf@gitster-ct.c.googlers.com>

Junio C Hamano <gitster@pobox.com> writes:

Show 9 quoted lines

> Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
>
>> I would like to ask you to reinstate the post-rewrite hook, as it still
>> improves the situation over the current one.
>
> Without post-rewrite I seem to be getting correct amlog entries for
> commits created by "git rebase"; do our rebase--am backend still
> trigger post-applypatch hook in its "am" phase to apply the patches
> created with "format-patch"?

That was a wrong line of thought that led to a dead end. format-patch won't recreate Message-Id to its output from notes/amlog, so even if the "format-patch --stdout | am" pipeline inside rebase-am triggered the post-applypatch hook, it would not have a chance to carry the notes forward that way.

What was really happening was I have

	$ git config --list | grep amlog
	notes.rewriteref=refs/notes/amlog

and that ought to be sufficient to carry "commit-to-original-msg-id" entries across rebases. And it seems to correctly work. I however suspect that "cherry-pick A..B" may lose the notes, but I haven't checked.