From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: cmd_cherry in builtin/log.c?
Date: Tue, 7 Dec 2010 11:39:23 -0600
Message-ID: <20101207173923.GA21483@burratino>
References: <AANLkTikXmc-3BBkxy-D8GNLAMXUOPghp78GpStZ-_wBW@mail.gmail.com>
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Cc: Git Mailing List <git@vger.kernel.org>, rene.scharfe@lsrfire.ath.cx
To: Thiago Farina <tfransosi@gmail.com>
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Hi,

Thiago Farina wrote:

> I was looking into builtin/log.c to see how it does --reverse and I
> saw that cmd_cherry is there.
> 
> I'm wondering, why is it there?

Good question.  So let's check.

 $ git log --oneline -Scmd_cherry builtin/log.c
 81b50f3 Move 'builtin-*' into a 'builtin/' subdirectory

That wasn't too helpful.  Okay, okay.

 $ git log --oneline -Scmd_cherry -- builtin-log.c
 81b50f3 Move 'builtin-*' into a 'builtin/' subdirectory
 e827633 Built-in cherry

Running "git show e827633" reveals that the core of the original
script is

	for c in $inup
	do
		git-diff-tree -p $c
	done | git-patch-id |
	while read id name
	do
		echo $name >>$patch/$id
	done

while the core of the builtin version is

	get_patch_ids(&revs, &patch_id_opts, prefix);

The latter function is static, introduced by v1.4.1~12^2~5
(format-patch: introduce "--ignore-if-in-upstream", 2006-06-25).

So the answer is that "git cherry" is considered a variant on
"git log" (like format-patch, show, and whatchanged) and that it uses
"git log" internals.

Hope that helps,
Jonathan