bug#29363: Single test failure building Guix

[ludo@gnu.org (Ludovic Courtès)]

Hello,

Marius Bakke <mbakke@fastmail.com> skribis:

> Rutger Helling <rhelling@mykolab.com> writes:
>
>> when building Guix with 'guix build guix' I keep running into a single 
>> test failure. I've attached the test-suite.log.
>
> Is this a Btrfs system by any chance, possibly on an SSD?
>
>> test-name: dead path can be explicitly collected
>> location: /tmp/guix-build-guix-0.13.0-10.0b4c385.drv-0/source/tests/store.scm:178
>> source:
>> + (test-assert
>> +   "dead path can be explicitly collected"
>> +   (let ((p (add-text-to-store
>> +              %store
>> +              "random-text"
>> +              (random-text)
>> +              '())))
>> +     (let-values
>> +       (((paths freed) (delete-paths %store (list p))))
>> +       (and (equal? paths (list p))
>> +            (> freed 0)
>> +            (not (file-exists? p))))))
>> actual-value: #f
>> result: FAIL
>
> I can reproduce this error on two different systems that have
> Btrfs+LUKS+SSD, and the problem is that freed == 0.

If you comment out (> freed 0), does the test pass?

> I suspect it's related to Btrfs' "lazy" reporting of disk space, but
> haven't dug very far.
>
> Until we figure out what's going on, I suggest applying the patch
> below.  Can you confirm that it works on your system?
>
> From bdc7b5310111e21801529ea57e290f6eb72ac6ed Mon Sep 17 00:00:00 2001
> From: Marius Bakke <mbakke@fastmail.com>
> Date: Tue, 21 Nov 2017 00:27:08 +0100
> Subject: [PATCH] gnu: guix: Disable test that fails on Btrfs.
>
> Works around <https://bugs.gnu.org/29363>.
> Reported by Rutger Helling <rhelling@mykolab.com>.
>
> * gnu/packages/package-management.scm (guix)[arguments]: Rename
> 'disable-container-tests' phase to 'disable-failing-tests' and add substitution
> to disable "dead path can be explicitly collected" test.

Alternately, we could comment out (> freed 0) if that’s enough, with a
comment explaining why, and do “make update-guix-package”.  That way
we’d avoid the extra build phase.

WDYT?

Thanks for finding out the root cause!

Ludo’.