From: Christian Couder <chriscool@tuxfamily.org>
Date: Fri, 23 May 2014 06:39:54 GMT
Subject: Re: [RFC/PATCH] replace: add --graft option
Message-ID: <20140523.083954.56876133762506067.chriscool@tuxfamily.org>
In-Reply-To: <5379D1EF.8040203@alum.mit.edu>

From: Michael Haggerty <mhagger@alum.mit.edu>

> On 05/18/2014 08:29 PM, Christian Couder wrote:
>> The usage string for this option is:
>> 
>> git replace [-f] --graft <commit> [<parent>...]
>> 
>> First we create a new commit that is the same as <commit>
>> except that its parents are [<parents>...]
>> 
>> Then we create a replace ref that replace <commit> with
>> the commit we just created.
>> 
>> With this new option, it should be straightforward to
>> convert grafts to replace refs, with something like:
>> 
>> cat .git/info/grafts | while read line
>> do git replace --graft $line; done
> 
> I love the functionality; I think it's a great step towards making
> grafts obsolete.
> 
> I haven't worked with Git's object reading/writing code much, but it
> surprised me that you are editing the commit object basically as a
> string, using hard-coded length constants and stuff.  It seems
> error-prone, and we already have a commit parser.
> 
> Would it be possible to program this at a higher layer of abstraction
> based on the commit object produced by the existing commit parser?
> E.g., edit the object it produces, and write the result?  Or create a
> new commit object out of the parsed commit object and write that?

I tried to program this at a higher layer of abstraction first, but it
was not easy to properly write the new commit.

> It's great that you're working on this!

Thanks,
Christian.