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From: Junio C Hamano <gitster@pobox•com>
To: Jon Loeliger <jdl@freescale•com>
Cc: Git List <git@vger•kernel.org>
Subject: Re: Octopus?  Really?  Interesting...
Date: Fri, 04 Jan 2008 14:42:57 -0800	[thread overview]
Message-ID: <7vhchti55a.fsf@gitster.siamese.dyndns.org> (raw)
In-Reply-To: <1199471321.3133.22.camel@ld0161-tx32> (Jon Loeliger's message of "Fri, 04 Jan 2008 12:28:41 -0600")

Jon Loeliger <jdl@freescale•com> writes:

> Couple questions:
>
>     Is it ever NOT the case, that if you are on one
>     branch ("master") and name it as a "to be merged"
>     branch along with some others, that we can simplify
>     the request by noting that it is the same as the
>     current "to be merged into" target branch?

Yes we can, but "filter ancestors out from the remotes"
computation does not happen before the merge strategy is chosen.

>     Other than creating a log message with "merged
>     by octopus", will this merge be content-identical
>     to the obvious simplified merge?

I think octopus actually tries to be careful not to run the
read-tree 3-way merge when merging a true ancestor (see ll.77-87
in git-merge-octopus.sh, but see below), so the resulting tree
should be identical to "-s resolve" merge.

But that does not mean the user's wish to record such a commit
as one ancestor should not be honored, and I think there
actually is a benign bug there.  Due to the "Already up-to-date
with $SHA1" part, the codepath that says "Fast forwarding to:"
never actually triggers, so in practice we end up dropping any
true ancestor from the parent list of the resulting merge.  That
contradicts the comment in ll.77-87 that suggests we try not to
outsmart the user who told us to create such an octopus for
unfathomable reason ;-)

      reply	other threads:[~2008-01-04 22:43 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-01-04 18:28 Octopus? Really? Interesting Jon Loeliger
2008-01-04 22:42 ` Junio C Hamano [this message]

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