Subject: Re: [BUG] rebase no longer omits local commits

From: John Keeping <[email-masked]>
Date: Thu, 3 Jul 2014 20:09:17 +0100

On Thu, Jul 03, 2014 at 11:14:26AM -0400, Ted Felix wrote:
> Starting with git 1.9.0, rebase no longer omits local commits that 
> appear in both the upstream and local branches.
> 
> I've bisected this down to commit bb3f458: "rebase: fix fork-point with 
> zero arguments".  The attached script reproduces the problem.  Reverting 
> the aforementioned commit fixes the problem.
> 
> A failed run of this script will result in conflicts.  A successful run 
> against master with bb3f458 reverted ends as follows:
> 
>  From /tmp/rebase-issue/maint
>     fe401cd..955af04  master     -> origin/master
> fatal: Not a valid object name: ''
> First, rewinding head to replay your work on top of it...
> Applying: Third change
> 
> (I'm not sure if that "fatal: Not a valid object name: ''" is of any 
> concern.  It started appearing for me at some point during the bisect.)

It is the problem that bb3f458 fixes.  The change in behaviour is
actually introduced by ad8261d (rebase: use reflog to find common base
with upstream).

In your example, I think this is working as designed.  You can restore
the previous behaviour either with `git rebase --no-fork-point` or with
`git rebase @{u}`.

The change is designed to help users recover from an upstream rebase, as
described in the "DISCUSSION ON FORK-POINT MODE" section of
git-merge-base(1) and makes `git rebase` match the behaviour of
`git pull --rebase` so that:

	git fetch &&
	git rebase

really is equivalent to:

	git pull --rebase