import gc def test_weak_method_on_obj(): from kivy.weakmethod import WeakMethod class SomeClass: def do_something(self): pass obj = SomeClass() weak_method = WeakMethod(obj.do_something) assert not weak_method.is_dead() assert weak_method() == obj.do_something assert weak_method == WeakMethod(obj.do_something) assert weak_method != WeakMethod(SomeClass().do_something) del obj gc.collect() assert weak_method.is_dead() assert weak_method() is None assert weak_method != WeakMethod(SomeClass().do_something) def test_weak_method_func(): from kivy.weakmethod import WeakMethod def do_something(): pass weak_method = WeakMethod(do_something) assert not weak_method.is_dead() assert weak_method() == do_something assert weak_method == WeakMethod(do_something) del do_something gc.collect() assert not weak_method.is_dead() assert weak_method() is not None