Re: Testing if a certain commit is in the current branch

From: Frans Pop <elendil@planet.nl>
Date: Jan 27, 2010, 15:27 UTC
Message-ID: <201001271627.45715.elendil@planet.nl>
In-Reply-To: <20100127150834.GG9553@machine.or.cz>

On Wednesday 27 January 2010, Petr Baudis wrote:

Show 7 quoted lines

> > Great! If the commit ID is not present that only takes 1 sec versus 11
> > secs for my test. (If the commit _is_ present and fairly recent my
> > test can be faster, but 11 secs delay when it's not present hurts
> > more.)
>
> Isn't something very wrong if grepping the log output is faster than
> simple merge-base call? Can you post exact numbers?

It's only faster if the commit is present very early in the log. The reason is probably that because of the '-q' option it does not actually read the full log, but breaks out as soon as it's found a match.

In my test I had an elapsed time of ~0.5 sec (versus 1 sec for Junio's test). And here's a grep for the very first commit:

$ time git log --pretty=format:%H | grep -q 48404cb50b0b547

real 0m0.010s user 0m0.000s sys 0m0.012s