RE: Amending merge commits?

From: Besen, David <david.besen@hp.com>
Date: Jul 25, 2014, 22:23 UTC
Message-ID: <22F01493C523F940B4B5E53BB6D0F5352275F25B@G5W2738.americas.hpqcorp.net>
In-Reply-To: <20140725221911.GL12427@google.com>

Ah thanks, I'll RTFM better in the future.

- Dave

-----Original Message-----
From: Jonathan Nieder [mailto:jrnieder@gmail.com] 
Sent: Friday, July 25, 2014 4:19 PM
To: Besen, David
Cc: git@vger.kernel.org
Subject: Re: Amending merge commits?

Besen, David wrote:

> I think one of my coworkers has stumbled on a git bug -- if you
> amend a merge commit, and then pull, your amends are lost.

This is how pull --rebase works. It turns your single-parent commits into a sequence of patches on top of upstream and completely ignores your merge commits.

There is a --rebase=preserve option that makes a halfhearted attempt to preserve your merges --- perhaps that would help? The git-rebase(1) documentation has more details.

In an ideal world, I think pull --rebase would do the following:

 1. Do the same thing it does today
 2. Behind the scenes, *also* try a 'pull --merge' but don't save
    the result.
 3. Compare the results.  If they differ, show a diff and explain
    to the user what happened.

I may be the only one that wants that, though.

Hope that helps, Jonathan