Re: [PATCH][OUTREACHY] bisect: allow `git bisect` to run from subdirectory

From: Junio C Hamano <gitster@pobox.com>
Date: Oct 21, 2020, 19:53 UTC
Message-ID: <xmqqr1pr73ve.fsf@gitster.c.googlers.com>
In-Reply-To: <20201021162044.GB111581@nand.local>

Taylor Blau <me@ttaylorr.com> writes:

Show 9 quoted lines

> I'm not sure that that's the case: Junio pointed out a while[1] ago that
> we'd have to answer the question of "what happens if I'm in a
> subdirectory that goes away during some point of the bisection?". I
> think that you could probably find an answer to that question, but the
> fact that there isn't an obvious one seems to indicate that we're going
> down the wrong path.
>
> I agree that it would be nice to run bisect from any directory, but it
> may not be as easy as I'd hope.

True.

I would not mind all that much a single "git checkout ancient" that makes the $cwd go away and confuse the user. But a bisect session would jump around versions randomly (eh, logarithmically?) and you'd end up switching out of a version in a non-existing $cwd to another version that has the directory (created internally by mkdir(2)), and I'm fairly certain that your phantom $cwd that is not connected to any other filesystem entity and the directory that should be at the same path in the newly checked-out version are different filesystem entities. I'd rather not have to think about the interaction between git and the system after that point.

Thanks.