def test_4(self): t = Tree() t.add_child(Tree()) t.add_child(Tree()) t.get_children()[1].add_child(Tree()) self.assertEqual(t.get_children()[0].next_leaf, t.get_children()[1].get_children()[0])
def test_of_last_leaf(self): t = Tree() t.add_child(Tree()) t.add_child(Tree()) self.assertIsNone(t.get_children()[1].next_leaf)
def test_3(self): t = Tree() t.add_child(Tree()) t.add_child(Tree()) self.assertEqual(t.get_children()[1].previous_leaf, t.get_children()[0])
def test_2(self): t = Tree() t.add_child(Tree()) t.add_child(Tree()) self.assertIsNone(t.get_children()[0].previous_leaf)