From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: Amending merge commits?
Date: Fri, 25 Jul 2014 15:19:11 -0700
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To: "Besen, David" <david.besen@hp.com>
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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