Re: [PATCH v1] rebase -m: Use empty tree base for parentless commits

From: Junio C Hamano <gitster@pobox.com>
Date: Oct 9, 2014, 20:18 UTC
Message-ID: <xmqqoatl574t.fsf@gitster.dls.corp.google.com>
In-Reply-To: <5436E83A.7070603@gmail.com>

Fabian Ruch <bafain@gmail.com> writes:

Show 6 quoted lines

>> The interface to "git-merge-$strategy" is designed in such a way
>> that each strategy should be capable of taking _no_ base at all.
>
> The merge strategies "resolve" and "octopus" seem to refuse to run if no
> base is specified. The former silently exits if no bases are given and
> the latter dies saying "Unable to find common commit".

That just means these two strategies are not prepared to do a merge without base (yet). It does not automatically give license to the caller to pass a random tree as if it is the merge base the user wanted to use.

For "resolve", I think it is OK for it to detect that the caller did not give a common ancestor tree and use an empty tree when merging (which is what merge-recursive ends up doing internally).

I am not offhand sure if the same is sensible for "octopus", though.