Re: Adding a line after the signed-off git am -s

[Junio C Hamano <gitster@pobox.com>]

Daniel Lezcano <daniel.lezcano@linaro.org> writes:

> I would like to do something:
>
> git am -s -l "Link: https://lore.kernel.org/r/<msgid>"
>
> Which will give:
>
> blabla
>
> Signed-off-by: author@kairnail.org
> Signed-off-by: commiter@kairnail.org
> Link: https://lore.kernel.org/r/<msgid>
>
> This way it is compatible with patchwork, git-pw, etc...

There is the post-applypatch hook you can define after the patch
gets applied and produces a commit.

I use it to maintain the amlog notes in my repository (iow, I do not
amend the commit, but add notes to the resulting commit so that I
can tell, given a commit, which message resulted in it).  

If you want to amend the resulting commit instead, the place to do
so would be where I call "git notes --ref amlog" in the sample
script.

-- >8 -- post-applypatch hook example -- >8 --
#!/bin/sh

GIT_DIR=.git
dotest="$GIT_DIR/rebase-apply"

prec=4 &&
this=$(cat 2>/dev/null "$dotest/next") &&
msgnum=$(printf "%0${prec}d" $this) &&
test -f "$dotest/$msgnum" &&
message_id=$(sed -ne '
	/^[ 	]/{
		# Append continuation line to hold space
		H
		# Swap hold and pattern
		x
		# Remove the LF, making it a single line
		s/\n//
		# Swap hold and pattern back
		x
		# Discard the pattern and go on
		n
	}
	# Hold this new line, and look at what is in the hold space
	x
	# Is it the Message-ID line?  If so, spit it out and finish.
	/^[Mm][Ee][Ss][Ss][Aa][Gg][Ee]-[Ii][Dd]:[ 	]*/{
		s///p
		q
	}
	# Otherwise, check if this new line is empty
	x
	# Is it?  Then we are done with the header
	/^$/b end
	# Otherwise we need to hold onto this header line
	x
	# And start the next cycle
	b
: end
	# ??? do we want to check if we held onto the last message-id line
	# and process it here if we did???
	q
' "$dotest/$msgnum") &&

if	test -n "$message_id" &&
	head=$(git rev-parse --verify HEAD 2>/dev/null)
then
	echo "$head $message_id" >>"$GIT_DIR"/am.log &&
	git notes --ref amlog add -f -m "Message-Id: $message_id" "$head"
fi