Collection fails in python 2.6 if mock.call is imported

[dairiki]

As of yet, I have no idea why this happens, but, using

• python 2.6
• mock 1.3.0
• py.test 2.8.1 (or 2.8.0)

With test_mock.py containing the single line:

from mock import call

py.test test_mock.py fails with

============================= test session starts ==============================
platform linux2 -- Python 2.6.8, pytest-2.8.0, py-1.4.30, pluggy-0.3.1
rootdir: /srv/w/users/dairiki/git/discnw/btp_buildout, inifile: pytest.ini
collected 0 items / 1 errors 

==================================== ERRORS ====================================
______________________ ERROR collecting junk/test_mock.py ______________________
py26/lib/python2.6/site-packages/_pytest/runner.py:149: in __init__
    self.result = func()
py26/lib/python2.6/site-packages/_pytest/main.py:437: in _memocollect
    return self._memoizedcall('_collected', lambda: list(self.collect()))
py26/lib/python2.6/site-packages/_pytest/main.py:317: in _memoizedcall
    res = function()
py26/lib/python2.6/site-packages/_pytest/main.py:437: in <lambda>
    return self._memoizedcall('_collected', lambda: list(self.collect()))
py26/lib/python2.6/site-packages/_pytest/python.py:575: in collect
    return super(Module, self).collect()
py26/lib/python2.6/site-packages/_pytest/python.py:435: in collect
    l.sort(key=lambda item: item.reportinfo()[:2])
py26/lib/python2.6/site-packages/_pytest/python.py:435: in <lambda>
    l.sort(key=lambda item: item.reportinfo()[:2])
py26/lib/python2.6/site-packages/_pytest/python.py:371: in reportinfo
    assert isinstance(lineno, int)
E   assert isinstance(compat_co_firstlineno, int)
=========================== 1 error in 0.26 seconds ============================

This same error seems to happen when collecting tests from any source which includes a from mock import call.

(This does not happen with pytest < 2.8. Also this does not seem to be a problem with python 2.7.)

[The-Compiler]

Closing as a duplicate of #1035 and #1044.

[dairiki]

Sorry for the dup. Thanks for the pointers!