def test_bool(self):
        prio_set_list = event._PrioritizedSetList()

        assert bool(prio_set_list) is False

        prio_set_list.add(0, None)
        assert bool(prio_set_list) is True
def _update_dimension(
        self,
        size_diff,
        total_size,
        max_visible_size,
        dimension_request_property):
    if max_visible_size is None:
      is_max_visible_size_unlimited = True
    else:
      is_max_visible_size_unlimited = max_visible_size <= 0