def test_non_callable(self):
        with pytest.raises(TypeError) as excinfo:
            event.event(123)
        excinfo.match(r"Expected string, callable or None as first argument")

        with pytest.raises(TypeError) as excinfo:
            event.event("name")([])
        excinfo.match(r"Callable must be a function \(`def`\)"
                      r" or coroutine function \(`async def`\)")
def test_exceptions(self):
        self.assert_(issubclass(DeoptionError, TypeError))
        self.assertRaises(TypeError,
            lambda: Optional()
        )
        self.assertRaises(TypeError,
            lambda: Optional(NotPassed, NotPassed)
        )