From: Jeff King <peff@peff.net>
Date: Thu, 25 May 2017 18:04:07 GMT
Subject: Re: `pull --rebase --autostash` fails when fast forward in dirty repo
Message-ID: <20170525180407.ni2oed5wk3qsd2ch@sigill.intra.peff.net>
In-Reply-To: <xmqqa863jiyf.fsf@gitster.mtv.corp.google.com>

On Wed, May 24, 2017 at 07:40:08AM +0900, Junio C Hamano wrote:

> > But I notice on the run_merge() code path that we do still invoke
> > git-merge.
> 
> ... wouldn't that what we want even when the merge happens to be a
> fast-forward one?  I am not sure what you meant by this, but...

I just meant that if the point of the optimization was to avoid invoking
git-rebase (because it's slow), then we're still not optimizing out a
process. It only helps at all because "rebase" (being a shell script)
may be slower to start and realize it's a fast-forward than "merge".

But once that is no longer true of git-rebase, then there is no purpose
to the optimization.

> > And rebase has been getting faster as it is moved to C code
> > itself. So is this optimization even worth doing anymore?
> 
> ...that might be something worth thinking about---my gut feeling
> tells me something but we should go by a measurement, not by gut
> feeling of a random somebody.

Yeah, I'd agree. I had the impression the original change was motivated
by gut feeling.

-Peff