From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: possible bug in git apply?
Date: Mon, 06 Aug 2007 01:29:46 -0700
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To: Linus Torvalds <torvalds@linux-foundation.org>
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	(Linus Torvalds's message of "Sun, 5 Aug 2007 09:59:03 -0700 (PDT)")
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Linus Torvalds <torvalds@linux-foundation.org> writes:

> That said, if we really wanted to get it right, we should do this as a 
> three-phase thing: (1) remove old files (2) create new files (3) for all 
> removals and renames, try to remove source directories that might have 
> become empty.
>
> That would fix it properly and for all cases.

Actually that will break the case of removing foo/bar, which is
the only file in directory foo, and creating a new file foo.  So
if we really want to do all the corner cases, we would need to
do something like:

 * scan the list of files that will remain (i.e., renamed-to,
   modifed-in-place and created-anew) to note which directories
   should remain in the result;

 * remove old files, and remove its empty parent directories
   that are not in the above list;

 * create new files.

But in the meantime for 1.5.3, I think your patch is better than
what we currently have.