def test_can_successfully_add_a_left_child_and_right_child_to_a_single_root_node():
new_tree = BinaryTree()
new_tree.root = Node(1)
new_tree.root.left = Node(2)
new_tree.root.right = Node(3)
expected = [1, 2, 3]
actual = new_tree.preOrder()
assert expected == actual
def test_can_successfully_return_a_collection_from_a_preorder_traversal():
new_tree = BinaryTree()
new_tree.root = Node("A")
new_tree.root.left = Node("B")
new_tree.root.right = Node("C")
new_tree.root.right.left = Node("F")
new_tree.root.left.left = Node("D")
new_tree.root.left.right = Node("E")
expected = ["A", "B", "D", "E", "C", "F"]
actual = new_tree.preOrder()
assert expected == actual
def test_4 ():
node1 = TNode(1)
node1.left = TNode(2)
node1.right = TNode(3)
node1.right.left = TNode(5)
node1.right.right = TNode(4)
node1.left.right = TNode(6)
node1.left.left = TNode(7)
binary_tree = BinaryTree(node1)
actual = binary_tree.preOrder().__str__()
expected = '-> 4 -> 5 -> 3 -> 6 -> 7 -> 2 -> 1 -> None'
assert actual == expected
def test_instantiate_an_empty_tree():
expected = []
btt = BinaryTree()
actual = btt.preOrder()
assert actual == expected
def test_instantiate_tree_with_single_root():
expected = [5]
node = Node(5)
btt = BinaryTree(node)
actual = btt.preOrder()
assert actual == expected