Re: [PATCH] merge: allow using --no-ff and --ff-only at the same time

From: Junio C Hamano <gitster@pobox.com>
Date: Jul 1, 2013, 16:43 UTC
Message-ID: <7va9m6i63i.fsf@alter.siamese.dyndns.org>
In-Reply-To: <20130701161009.GI17269@suse.cz>

Miklos Vajna <vmiklos@suse.cz> writes:

> OK, so if I get it right, the problem is that users got used to
> that the --ff-only not only means a precondition for the merge,
> but also means "either don't create a merge commit or fail", while
> my patch would change this second behaviour.

It is not just "users got used to". "We do not want to create a merge commit with this operation." is what "--ff-only" means from the day one [*1*].

For a merge not to create an extra merge commit, the other history has to be a proper descendant, but that "precondition" is a mere logical consequence of the ultimate goal of the mode.

> I could imagine then new switches, like 'git merge --pre=ff
> --update=no-ff" could provide these, though I'm not sure if it makes
> sense to add such generic switches till the only user is "ff".

Yes, that is why I said "if one were designing it from scratch, I could see..." in a very weak form.

[Footnote]

*1* 13474835 (Teach 'git merge' and 'git pull' the option --ff-only, 2009-10-29) and also $gmane/107768 whose documentation part says:

  "Refuse to merge unless the merge is resolved as a fast-forward."