def test_entity_attributes(self):
cat = Entity()
with self.assertRaises(AttributeError):
cat.alive
catalive = Alive()
cat.components.add(catalive)
self.assertTrue(cat.alive)
cat.die()
self.assertFalse(cat.alive)
self.assertFalse(catalive.alive)
cat.components.remove(catalive)
with self.assertRaises(AttributeError):
cat.resurrect()
