def _swap_mut_subtree(tree: BinaryTree,
r: int,
random_tree: BinaryTree) -> BinaryTree:
"""Add mutated subtree to original tree.
:param tree:
:param r:
:param random_tree:
:return:
"""
# swap parents of nodes
node = tree.select_postorder(r)
if node.parent:
if node.parent.left is node:
node.parent.left = random_tree.root
elif node.parent.right is node:
node.parent.right = random_tree.root
random_tree.root.parent = node.parent
return tree
else:
new_tree = BinaryTree()
new_tree.root = random_tree.root
return new_tree
class TestBinaryTree(TestCase):
def setUp(self):
self.tree = BinaryTree()
self.root = BinaryTreeNode('*')
self.tree.root = self.root
def test_root(self):
tree = BinaryTree()
with self.assertRaises(TypeError):
tree.root = 'bad type'
def test_create_graph(self):
result = self.tree.create_graph()
self.assertIsInstance(result, Digraph)
def test_select_postorder(self):
left = self.root.add_left(20)
right = self.root.add_right(30)
ll = left.add_left(40)
lr = left.add_right(50)
rl = right.add_left(60)
rr = right.add_right(70)
self.assertEqual(self.tree.select_postorder(0), ll)
self.assertEqual(self.tree.select_postorder(1), lr)
self.assertEqual(self.tree.select_postorder(2), left)
self.assertEqual(self.tree.select_postorder(3), rl)
self.assertEqual(self.tree.select_postorder(4), rr)
self.assertEqual(self.tree.select_postorder(5), right)
self.assertEqual(self.tree.select_postorder(6), self.root)
def test_height(self):
tree = BinaryTree()
self.assertEqual(tree.height(), 0)
tree.root = BinaryTreeNode('*')
self.assertEqual(tree.height(), 1)
left = tree.root.add_left(10)
self.assertEqual(tree.height(), 2)
right = tree.root.add_right(20)
self.assertEqual(tree.height(), 2)
ll = left.add_left(40)
self.assertEqual(tree.height(), 3)
left.add_right(50)
self.assertEqual(tree.height(), 3)
right.add_left(60)
self.assertEqual(tree.height(), 3)
right.add_right(70)
self.assertEqual(tree.height(), 3)
ll.add_left(80)
self.assertEqual(tree.height(), 4)
def test_infix_tokens(self):
left = self.root.add_left('+')
right = self.root.add_right('+')
left.add_left('A')
left.add_right('B')
right.add_left('C')
right.add_right('D')
tokens = [
'(', '(', 'A', '+', 'B', ')', self.tree.root.label, '(', 'C', '+',
'D', ')', ')'
]
result = self.tree.infix_tokens()
self.assertCountEqual(result, tokens)
def test_postfix_tokens(self):
tree = BinaryTree()
root = BinaryTreeNode('*')
tree.root = root
left = root.add_left('+')
right = root.add_right('+')
left.add_left('A')
left.add_right('B')
right.add_left('C')
right.add_right('D')
tokens = ['A', 'B', 'C', tree.root.label, '+', 'D', '+']
result = tree.postfix_tokens()
self.assertCountEqual(result, tokens)
tree = BinaryTree()
root = BinaryTreeNode('+')
tree.root = root
left = root.add_left('+')
right = root.add_right('+')
left.add_left('A')
left.add_right('B')
right.add_left('C')
right.add_right('D')
tokens = ['A', 'B', '+', 'C', '+', 'D', '+']
result = tree.postfix_tokens()
self.assertCountEqual(result, tokens)