Can't run coverage with pytest 3.10.0

[albertodonato]

After upgrading to pytest 3.10.0, pytest --cov now fails with the following error:

INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/_pytest/main.py", line 185, in wrap_session
INTERNALERROR>     session.exitstatus = doit(config, session) or 0
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/_pytest/main.py", line 225, in _main
INTERNALERROR>     config.hook.pytest_runtestloop(session=session)
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/hooks.py", line 284, in __call__
INTERNALERROR>     return self._hookexec(self, self.get_hookimpls(), kwargs)
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/manager.py", line 67, in _hookexec
INTERNALERROR>     return self._inner_hookexec(hook, methods, kwargs)
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/manager.py", line 61, in <lambda>
INTERNALERROR>     firstresult=hook.spec.opts.get("firstresult") if hook.spec else False,
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/callers.py", line 203, in _multicall
INTERNALERROR>     gen.send(outcome)
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/callers.py", line 80, in get_result
INTERNALERROR>     raise ex[1].with_traceback(ex[2])
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/callers.py", line 187, in _multicall
INTERNALERROR>     res = hook_impl.function(*args)
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/_pytest/main.py", line 246, in pytest_runtestloop
INTERNALERROR>     item.config.hook.pytest_runtest_protocol(item=item, nextitem=nextitem)
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/hooks.py", line 284, in __call__
INTERNALERROR>     return self._hookexec(self, self.get_hookimpls(), kwargs)
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/manager.py", line 67, in _hookexec
INTERNALERROR>     return self._inner_hookexec(hook, methods, kwargs)
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/manager.py", line 61, in <lambda>
INTERNALERROR>     firstresult=hook.spec.opts.get("firstresult") if hook.spec else False,
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/callers.py", line 208, in _multicall
INTERNALERROR>     return outcome.get_result()
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/callers.py", line 80, in get_result
INTERNALERROR>     raise ex[1].with_traceback(ex[2])
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/callers.py", line 187, in _multicall
INTERNALERROR>     res = hook_impl.function(*args)
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/_pytest/runner.py", line 78, in pytest_runtest_protocol
INTERNALERROR>     item.ihook.pytest_runtest_logfinish(nodeid=item.nodeid, location=item.location)
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/hooks.py", line 284, in __call__
INTERNALERROR>     return self._hookexec(self, self.get_hookimpls(), kwargs)
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/manager.py", line 67, in _hookexec
INTERNALERROR>     return self._inner_hookexec(hook, methods, kwargs)
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/manager.py", line 61, in <lambda>
INTERNALERROR>     firstresult=hook.spec.opts.get("firstresult") if hook.spec else False,
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/callers.py", line 208, in _multicall
INTERNALERROR>     return outcome.get_result()
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/callers.py", line 80, in get_result
INTERNALERROR>     raise ex[1].with_traceback(ex[2])
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/pluggy/callers.py", line 187, in _multicall
INTERNALERROR>     res = hook_impl.function(*args)
INTERNALERROR>   File "/home/ack/prj/.ve/lib/python3.6/site-packages/_pytest/terminal.py", line 432, in pytest_runtest_logfinish
INTERNALERROR>     len(self._progress_nodeids_reported) == self._session.testscollected
INTERNALERROR> AttributeError: 'NoneType' object has no attribute 'testscollected'

It worked fine with pytest 3.9.3.

[blueyed]

Does it only happen with pytest-cov?
Which other plugins are you using? pytest-sugar maybe? Would be Teemu/pytest-sugar#159 then.

[albertodonato]

@blueyed you're right, if I remove pytest-sugar, coverage works. I was tricked by the fact that running plain pytest without --cov worked even with pytest-sugar

[blueyed]

Interesting, thanks for the update.

[blueyed]

Hmm, according to Teemu/pytest-sugar#159 (comment) pytest-cov is not needed to trigger this.
Anyway, closing it here even though it is unclear what exactly triggers it.