Re: [PATCH] Teach applymbox to keep the Subject: line.

From: Linus Torvalds <torvalds@osdl.org>
Date: Aug 18, 2005, 20:07 UTC
Message-ID: <Pine.LNX.4.58.0508181257320.3412@g5.osdl.org>
In-Reply-To: <20050818172646.GA18459@mars.ravnborg.org>

On Thu, 18 Aug 2005, Sam Ravnborg wrote:

Show 5 quoted lines

> 
> I almost always handedit my mails and I find myself forgetting to add
> "Signed-off-by" from time to time.
> Is there a simple way to implment a trigger that can check that _I_
> signed off the patch before applying it?

Well, Junio has been talking about adding commit hooks. I don't think that's been done. The idea being that you could verify that the thing you're committing follows certain rules (no bad whitespace added in the diff, sign-offs in the messages, whatever).

That said, git-applypatch (which is what git-applymbox ends up calling) does not use the general "git commit" script. So it would have to have its own hook. The script is pretty easy to read, though: just look at git-applypatch, and notice that the last stages are:

	...
	git-apply --index $PATCHFILE || exit 1
	tree=$(git-write-tree) || exit 1
	echo Wrote tree $tree
	commit=$(git-commit-tree $tree -p $(cat .git/HEAD) < $final) || exit 1
	echo Committed: $commit
	echo $commit > .git/HEAD

and that just before this thing you could easily add some sanity checking by hand. The commit message at that point is in the "$final" file, and the patch is obviously in $PATCHFILE, so you can verify either of those to your hearts content.

The only question is what the hook/trigger should look like. just put something like

	[ -x .git/hooks/applypatch-hook ] &&
	     .git/hooks/applypatch-hook "$tree" "$PATCHFILE" || exit

at the line before that "git-apply" perhaps? Then, you could install your own applypatch hook which looks at the message or the patch?

		Linus