[Python-modules-team] Bug#890621: python3-keyrings.alt 2.2-2 module.__file__ is None, causing regrtest.py to fail

[Ron Lovell]

Package: python3-keyrings.alt
Version: 2.2-2
Severity: important

Dear Maintainer,

When package 'keyrings' from python3-keyrings.alt is imported under
python3.6, the module object has a __file__ attribute with a value None.
This causes early failure of the Python 3.6 regression tests  from
libpython3.6-testsuite.

The problem occurs starting at line 60 of
/usr/lib/python3.6/test/libregrtest/setup.py, within a loop on the
module objects listed in sys.modules.values().  The module object for
'keyrings' has a __file__ attribute, but it is None, so the call to
os.path.abspath() fails with a TypeError on the non-string argument
passed to it.

Please note that when the 'keyrings' package from python3-keyrings.alt is
imported into python3.7 (python3.7_3.7.0~b1-1_amd64), the
'keyrings' module object has no attribute __file__.  Hence the tests
from libpython3.7-testsuite run, even though libregrtest/setup.py
is identical to the 3.6 version.

Note also that when module keyrings.alt (as opposed to package
keyrings) is imported in python3.6, the 'keyrings.alt' module object
has a proper string-valued __file__ attribute.  That doesn't help with
the regression tests, however, since a 'keyrings' module object is
listed in sys.modules.values().

It would appear that initialized module objects from import of
package 'keyrings' should not have a __file__ attribute at all,
which is consistent with python3.7's initialization.

I happen to have python3-keyrings.alt installed because
python3-jupyter-core recs python3-pip, which  recs python3-wheel, which
recs python3-keyrings.alt. I could probably remove the package without
missing it.

But my current workaround, and one you might consider, is to modify
/usr/lib/python3.6/test/libregrtest/setup.py:

60c60
<         if hasattr(module, '__file__'):
---
>         if hasattr(module, '__file__') and module.__file__ != None:

-- System Information:
Debian Release: buster/sid
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 4.14.0-3-amd64 (SMP w/2 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages python3-keyrings.alt depends on:
ii  python3         3.6.4-1
ii  python3-crypto  2.6.1-8
ii  python3-six     1.11.0-2

python3-keyrings.alt recommends no packages.

Versions of packages python3-keyrings.alt suggests:
ii  gir1.2-gnomekeyring-1.0  3.12.0-1+b2
ii  python3-gi               3.26.1-2

-- no debconf information