Adam Williamson wrote:
> Take the current state of gnome-power-manager. Master is at:
>
> commit dfd0f074a7d41d355da28180eae1bda5dc2bba66
> Author: Richard Hughes <richard@xxxxxxxxxxx>
> Date: Mon Sep 26 16:58:28 2011 +0100
>
> New upstream version.
>
> f16 is at:
>
> commit b0b31219d2cfdffa815659a8aad78509b65c412a
> Author: Richard Hughes <richard@xxxxxxxxxxx>
> Date: Mon Oct 17 11:34:50 2011 +0100
>
> New upstream version.
>
> which is just a single commit ahead of the master branch.
What you need to do in this case is:
1. Identify the commit in f16 which made it contain the same contents as
master. (This is the magic ingredient in my recipe. If that state does not
exist, it can sometimes be produced by judicious use of cherry-pick or
revert.) In this case, this would have been commit
d13e25653fec0bb1e09c99badbecc84688b28cd8.
2. Switch the current branch to master.
3. git merge d13e25653fec0bb1e09c99badbecc84688b28cd8 (git will recognize
that the contents are identical and produce a trivial merge. No conflicts.)
4. git merge f16 (Now git will see from the history that only commit
b0b31219d2cfdffa815659a8aad78509b65c412a remains to be merged and merge
that. Again, no conflicts to deal with.)
5. Push your changes.
I use this trick very frequently and I'm surprised that so many people here
seem not to have figured it out yet (judging from the many complicated
suggestions of how to do this). I discovered it more or less by accident,
seeing how merges just worked if the trees were containing identical
contents with different history, but not when they were containing different
contents with different history. So I tried using the hash with identical
contents as the "branch" to merge and, hey, it worked! And now it sounds
obvious and straightforward to me.
Of course, I blame maintainers (or scripts! Rel-eng's release bumping script
is a big offender there) for committing the same thing to different branches
as different commit hashes instead of using merge in the first place…
Kevin Kofler
--
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxxx
https://admin.fedoraproject.org/mailman/listinfo/devel
