[Python-Dev] Failing tests (on a Linux distro)

[Petr Viktorin]

On 07/02/18 00:59, Miro Hrončok wrote:
> On 1.7.2018 23:48, Matěj Cepl wrote:
>> On 2018-06-28, 00:58 GMT, Ned Deily wrote:
>>> On behalf of the Python development community and the Python 3.7 release
>>> team, we are pleased to announce the availability of Python 3.7.0.
>>
>> I am working on updating openSUSE packages to python 3.7, but
>> I have hit quite large number of failing tests (the testsuite
>> obviously passed with 3.6), see
>> https://build.opensuse.org/package/show/home:mcepl:work/python3
>> (click on the red "failed" label to get logs). I fell into
>> a bout of depression, only to discover that we are not alone in
>> this problem ... Debian doesn't seem to do much better
>> https://is.gd/HKBU4j. Surprisingly, Fedora seems to pass the
>> testsuite https://is.gd/E0KA53; interesting, I will have to
>> investigate which of their many patches did the trick.
> 
> Note that we (=Fedora) unfortunately skip some tests.
> 
> https://src.fedoraproject.org/rpms/python3/blob/master/f/python3.spec#_1051
> 
> https://src.fedoraproject.org/rpms/python3/blob/master/f/00160-disable-test_fs_holes-in-rpm-build.patch 
> 
> 
> https://src.fedoraproject.org/rpms/python3/blob/master/f/00163-disable-parts-of-test_socket-in-rpm-build.patch 

[with my Fedora hat on]

Fedora* has been building python37 since the alphas, so the final update 
to rc/stable was smoother. But it also means we aren't solving the same 
issues as SUSE now, so we won't be able to help all that much :(
Do consider trying out alphas/betas in SUSE next time!
Anyway, the SUSE tests seem  to fail on .pyc files. The main change in 
that area was [PEP 552], try starting there. AFAIK, SUSE is ahead of 
Fedora in the reproducible builds area; perhaps that's where the 
difference is.

And while I'm responding here, a bit of reflection and a heads-up:
What Fedora as a distro should do better next time is re-build the 
entire ecosystem with a new Python version. For 3.7 we started doing 
that too late, and there are way too many projects that weren't prepared 
for `async` as keyword and PEP 479 (StopIteration handling).
If you run into similar problems in SUSE, you might want to take a look 
at issues tracked under [Fedora bug 1565020].


[PEP 552]: https://www.python.org/dev/peps/pep-0552/

[Fedora bug 1565020]: 
https://bugzilla.redhat.com/showdependencytree.cgi?id=1565020

* Thanks to Miro Hrončok for most of the work in Fedora