From: Michael J Gruber <git@drmicha.warpmail.net>
Date: Wed, 14 Nov 2012 13:28:00 GMT
Subject: Re: bug? git format-patch -M -D then git am fails
Message-ID: <50A39C60.7000005@drmicha.warpmail.net>
In-Reply-To: <7vfw4dccm7.fsf@alter.siamese.dyndns.org>

Junio C Hamano venit, vidit, dixit 14.11.2012 00:22:
> Joe Perches <joe@perches.com> writes:
> 
>> I don't believe that reversibility
>> is a really useful aspect of deletion patches
>> when there are known git repositories involved.
> 
> You can read "reversibility" as "safety" if you want.  We would want
> to make sure we know what we are deleting before deleting a path.
> 
> The history that the receiver of such a patch has may have further
> changes that are relevant that the sender of the deletion patch did
> not know about, and removing the path in such a case would make the
> result inconsistent.  If the sender did his work on top of the newer
> version with the change in the path, the sender's patch may still
> have deleted the path but would have had changes to other paths to
> compensate for the loss of that change.
> 

Just in case someone wants to hack on this: To be safe, "git am" would
need to read the blob's sha1 from something like

diff --git a/Makefile b/Makefile
deleted file mode 100644
index 1b6d84d..0000000

and check that the file to be deleted matches.

Michael