def test_add(self):
tree = Tree()
root = tree.add()
self.assertEqual(tree.add(), root.left)
self.assertEqual(tree.size(), 2)
self.assertEqual(tree.max_depth(), 2)
self.assertEqual(tree.add(), root.right)
self.assertEqual(tree.size(), 3)
self.assertEqual(tree.max_depth(), 2)
def test_root(self):
tree = Tree()
root = tree.add()
self.assertEqual(root, tree.root)
self.assertEqual(tree.size(), 1)
self.assertEqual(tree.max_depth(), 1)
self.assertEqual(list((n.node for n in tree)), [root])
self.assertEqual(list((n.node for n in tree.in_order())), [root])
self.assertFalse(root.left)
self.assertFalse(root.right)
def test_empty_tree(self):
tree = Tree()
self.assertEqual(tree.size(), 0)
self.assertEqual(tree.max_depth(), 0)
self.assertEqual(list(tree), [])