Re: [PATCH 2/5] t1400: set core.logAllRefUpdates in "logged by touch" tests

From: Jeff King <peff@peff.net>
Date: Mar 21, 2017, 01:49 UTC
Message-ID: <20170321014920.qas2xbbx66zqo5lp@sigill.intra.peff.net>
In-Reply-To: <20170321005616.31324-3-kyle@kyleam.com>

On Mon, Mar 20, 2017 at 08:56:13PM -0400, Kyle Meyer wrote:

Show 11 quoted lines

> A group of update-ref tests verifies that logs are created when either
> the log file for the ref already exists or core.logAllRefUpdates is
> "true".  However, when the default for core.logAllRefUpdates was
> changed in 0bee59186 (Enable reflogs by default in any repository with
> a working directory., 2006-12-14), the setup for the tests was not
> updated.  As a result, the "logged by touch" tests would pass even if
> the log file did not exist (i.e., if "--create-reflog" was removed
> from the first "git update-ref" call).
> 
> Update the "logged by touch" tests to disable core.logAllRefUpdates
> explicitly so that the behavior does not depend on the default value.

Good catch.

> While we're here, update the "logged by config" tests to use
> test_config() rather than setting core.logAllRefUpdates to "true"
> outside of the tests.

Yeah, I agree that makes the result more obvious to read.

Show 7 quoted lines

> I'm confused about the setup for the "logged by touch" tests.
> d0ab05849 (tests: remove some direct access to .git/logs, 2015-07-27)
> changed the setup to delete the log file itself rather than its
> contents.  The reflog was then recreated by using "--create-reflog" in
> the "create $m (logged by touch)" test.  What I don't understand is
> how this change fits with d0ab05849, which seems to be concerned with
> loosening the assumption that the logs are stored in .git/logs.

I suspect the answer is that the conversion was incomplete. That commit was done for alternate ref backends, which is an ongoing saga.

I think it's OK to leave it as-is for now. It's not clear what "logged by touch" will look like for backends that don't use the filesystem. Probably it will need to call "update-ref --create-reflog" to kickstart it, and then further updates will automatically write to it.

At that point the "rm -f" would need to become "tell the backend to delete this reflog". There's no command for that now, but we can add one later. Until then, I suspect the "rm -f" would be a noop. That means that the first --create-reflog test is failing to test what it claims, but the result passes anyway.

And that probably answers the question about why the conversion is half-done. It was enough to get the tests to stop complaining when built with an alternate ref backend. :)

Show 5 quoted lines

> For these particular tests, we are still removing
> .git/logs/refs/heads/master explictly, so why not leave the empty file
> around so that the "create $m (logged by touch)" actually tests that
> update-ref call is logged by the existence of the log rather than
> using "--create-reflog", which overrides this?

I think the tests just wanted to start at a known state. I agree that be correct (and would even work with an alternate backend), but it is a bit subtle that we are relying on the leftover state from the previous tests.

>  t/t1400-update-ref.sh | 23 ++++++++++++-----------
>  1 file changed, 12 insertions(+), 11 deletions(-)

Patch itself looks good.

-Peff