From: Jacob Keller <jacob.keller@gmail.com>
Date: Mon, 22 Feb 2016 07:30:37 GMT
Subject: Re: [RFC/PATCH 1/1] format-patch: add an option to record base tree info
Message-ID: <CA+P7+xqotNdbKHB4jbzEKZ7brPtz4vrg9HGBmia-aV2Z-kC=aQ@mail.gmail.com>
In-Reply-To: <xmqqmvqt8jgz.fsf@gitster.mtv.corp.google.com>

On Sun, Feb 21, 2016 at 8:19 PM, Junio C Hamano <gitster@pobox.com> wrote:
> If you are OK with accepting a patch application to a tree with the
> same blobs the diff was taken from, then the format-patch output
> already has all the necessary information.  For each "diff --git"
> part, there is the "index $old..$new" line that records preimage and
> postimage blob object ID, so you should be able to find a tree that
> has the matching blobs in the paths mentioned in the patch, and it
> is guaranteed that the patch would apply cleanly to such a tree.
>
> Of course, that requires the recipient of the patch to have the all
> the blobs mentioned as the preimage in the patch, but it would be a
> reasonable assumption, as your patch assumes that the recipient has
> the commit, and if he has a commit by definition he would have all
> the blobs recorded by that commit.
>

Sorry for a sort of tangent here, but what method would you recommend
for asking git to locate a commit which matches all those blobs? Is
there any already existing plumbing to do such a thing?

Regards,
Jake