--no-cov on pytest 4.0.0 produces warning

[sybrenstuvel]

Using pytest-cov 2.6.0 and pytest 4.0.0, running py.test --no-cov logs a long traceback with a warning that config.warn is deprecated:

% pipenv run py.test --no-cov
======================================================================================================== test session starts ========================================================================================================
platform linux -- Python 3.6.6, pytest-4.0.0, py-1.7.0, pluggy-0.8.0 -- /home/sybren/.virtualenvs/demo-VU2p87vc/bin/python3
cachedir: .pytest_cache
rootdir: /home/sybren/tmp/demo, inifile: setup.cfg
plugins: cov-2.6.0
collected 1 item                                                                                                                                                                                                                    

test_dummy.py::test_this PASSED                                                                                                                                                                                               [100%]
WARNING: Coverage disabled via --no-cov switch!
Traceback (most recent call last):
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/bin/py.test", line 11, in <module>
    sys.exit(main())
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/_pytest/config/__init__.py", line 77, in main
    return config.hook.pytest_cmdline_main(config=config)
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/hooks.py", line 284, in __call__
    return self._hookexec(self, self.get_hookimpls(), kwargs)
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/manager.py", line 67, in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/manager.py", line 61, in <lambda>
    firstresult=hook.spec.opts.get("firstresult") if hook.spec else False,
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/callers.py", line 208, in _multicall
    return outcome.get_result()
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/callers.py", line 80, in get_result
    raise ex[1].with_traceback(ex[2])
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/callers.py", line 187, in _multicall
    res = hook_impl.function(*args)
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/_pytest/main.py", line 218, in pytest_cmdline_main
    return wrap_session(config, _main)
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/_pytest/main.py", line 211, in wrap_session
    session=session, exitstatus=session.exitstatus
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/hooks.py", line 284, in __call__
    return self._hookexec(self, self.get_hookimpls(), kwargs)
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/manager.py", line 67, in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/manager.py", line 61, in <lambda>
    firstresult=hook.spec.opts.get("firstresult") if hook.spec else False,
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/callers.py", line 203, in _multicall
    gen.send(outcome)
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/_pytest/terminal.py", line 639, in pytest_sessionfinish
    terminalreporter=self, exitstatus=exitstatus
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/hooks.py", line 284, in __call__
    return self._hookexec(self, self.get_hookimpls(), kwargs)
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/manager.py", line 67, in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/manager.py", line 61, in <lambda>
    firstresult=hook.spec.opts.get("firstresult") if hook.spec else False,
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/callers.py", line 208, in _multicall
    return outcome.get_result()
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/callers.py", line 80, in get_result
    raise ex[1].with_traceback(ex[2])
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pluggy/callers.py", line 187, in _multicall
    res = hook_impl.function(*args)
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/pytest_cov/plugin.py", line 248, in pytest_terminal_summary
    terminalreporter.config.warn(code='COV-1', message=message)
  File "/home/sybren/.virtualenvs/demo-VU2p87vc/lib/python3.6/site-packages/_pytest/config/__init__.py", line 662, in warn
    lineno=lineno,
_pytest.warning_types.RemovedInPytest4Warning: config.warn has been deprecated, use warnings.warn instead

This can be reproduced by taking the attached demo.tar.gz and running pipenv run py.test --no-cov. I used Python 3.6.6 and Ubuntu 18.04. Note that py.test options are set in the setup.cfg file.

[blueyed]

Thanks for the report, fixed in #230 (just merged).