Re: [PATCH] user-manual: Talk about tracking third-party snapshots

From: Michael Smith <msmith@cbnco.com>
Date: Nov 13, 2007, 21:37 UTC
Message-ID: <Pine.LNX.4.64.0711131617580.4038@juice.ott.cti.com>
In-Reply-To: <7vtznqrlrb.fsf@gitster.siamese.dyndns.org>

On Tue, 13 Nov 2007, Junio C Hamano wrote:

> > +$ git checkout master
> > +$ git merge --strategy=ours \
> > +    -m "Tie old v1.1 into our history by merging with strategy=ours." \
> > +    v1.1

Show 5 quoted lines

> This would work only when your 'master' happens to be at v1.1
> (and identical to it) isn't it?
> 
> People would want to know "But my 'master' is _not_ at v1.1 but
> is _based_ on v1.1.  How would I handle that case?"

That was actually my case - my master was based on v1.1. The command worked for me - I was able to merge in v1.2 from Git afterward - but maybe I just got lucky, so I'd be interested to know the right thing to do.

I think --strategy=ours just leaves the files as is on master and creates a merge commit with two parents: master and v1.1. So anything between v1.1 and v1.2, on the upstream branch, is fair game to be merged next time.

So, say I started with this:

---------------
old snapshot branch: snap-v1.0---snap-v1.1
                       \           \
master:                 o---o---o---o--o-o

new Git upstream: o--o-v1.0-o-o-o-o-o-o-v1.1-o-o-v1.2 ---------------

I could make the merge with --strategy=ours:
---------------
old snapshot branch: snap-v1.0---snap-v1.1
                       \           \
master:                 o---o---o---o--o-o--o
                                           /
new Git upstream: o--o-v1.0-o-o-o-o-o-o-v1.1-o-o-v1.2
---------------

Then I'd free to merge in v1.2:
---------------
master:                 o---o---o---o--o-o--o------o
                                           /      /
new Git upstream: o--o-v1.0-o-o-o-o-o-o-v1.1-o-o-v1.2
---------------

Hmm, looks like a toothbrush. But is it right?

Mike