'Run check_coverage.py and make sure it\'s skipped.'

def check_skipped(self, args, reason):

    argv = ([sys.argv[0]] + list(args))
    self._monkeypatch.setattr(check_coverage.sys, 'argv', argv)
    with pytest.raises(check_coverage.Skipped) as excinfo:
        return check_coverage.check(None, perfect_files=[])
    assert (excinfo.value.reason == reason)
