From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Shawn O. Pearce" <spearce@spearce.org>
Subject: Re: committing empty diffs
Date: Mon, 12 Feb 2007 15:10:57 -0500
Message-ID: <20070212201057.GC30440@spearce.org>
References: <68948ca0702121149p4d87ae07jd3aa532a0df79156@mail.gmail.com> <20070212200324.GB30440@spearce.org>
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To: Don Zickus <dzickus@gmail.com>
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"Shawn O. Pearce" <spearce@spearce.org> wrote:
> Don Zickus <dzickus@gmail.com> wrote:
> > Considering git-commit doesn't allow this (probably for good reason),
> > is it technically safe to do the following sequence of events?
> > 
> > tree=$(git-write-tree)  #basically the same tree HEAD points to
> > commit=$(echo $IDEAS | git-commit-tree $tree -p HEAD)
> > git-update-ref HEAD $commit HEAD

This can also be written shorter, and safer:

	head=$(git-rev-parse --verify HEAD^0)
	commit=$(echo $IDEAS | git-commit-tree $head^{tree} -p $head)
	git-update-ref HEAD $commit $head

The reason you do it like this is it prevents a HEAD which was
modified between the time you did git-commit-tree and git-update-ref
from being lost.

And the write-tree is completely unnecessary, and might actually
write out a dirty-index, which would make your ideas commit actually
modifying files - not what you wanted.

-- 
Shawn.