Re: Bring together merge and rebase

[Carl Baldwin <carl@ecbaldwin.net>]

On Thu, Jan 04, 2018 at 12:54:00PM -0700, Martin Fick wrote:
> On Monday, December 25, 2017 06:16:40 PM Carl Baldwin wrote:
> > On Sun, Dec 24, 2017 at 10:52:15PM -0500, Theodore Ts'o 
> wrote:
> > Look at what happens in a rebase type workflow in any of
> > the following scenarios. All of these came up regularly
> > in my time with Gerrit.
> > 
> >     1. Make a quick edit through the web UI then later
> > work on the change again in your local clone. It is easy
> > to forget to pull down the change made through the UI
> > before starting to work on it again. If that happens, the
> > change made through the UI will almost certainly be
> > clobbered.
> > 
> >     2. You or someone else creates a second change that is
> > dependent on yours and works on it while yours is still
> > evolving. If the second change gets rebased with an older
> > copy of the base change and then posted back up for
> > review, newer work in the base change has just been
> > clobbered.
> > 
> >     3. As a reviewer, you decide the best way to explain
> > how you'd like to see something done differently is to
> > make the quick change yourself and push it up. If the
> > author fails to fetch what you pushed before continuing
> > onto something else, it gets clobbered.
> > 
> >     4. You want to collaborate on a single change with
> > someone else in any way and for whatever reason. As soon
> > as that change starts hitting multiple work spaces, there
> > are synchronization issues that currently take careful
> > manual intervention.
> 
> These scenarios seem to come up most for me at Gerrit hack-
> a-thons where we collaborate a lot in short time spans on 
> changes.  We (the Gerrit maintainers) too have wanted and 
> sometimes discussed ways to track the relation of "amended" 
> commits (which is generally what Gerrit patchsets are).  We 
> also concluded that some sort of parent commit pointer was 
> needed, although parent is somewhat the wrong term since 
> that already means something in git.  Rather, maybe some 
> "predecessor" type of term would be better, maybe 
> "antecedent", but "amended-commit" pointer might be best?

I like "replaces" as I have proposed or "supersedes". "predecessor" also
seems pretty good. I may add that to my list of favorites.

Carl