def test_in_order_traversal():
for nodes, expected_result in [
(
(
8,
[(4,
[2, 6]),
(10,
[None, 20])]
),
"2->4->6->8->10->20"
),
(
(1, ), "1"
),
(
(1, [2]), "2->1"
),
(
(1, [None, 2]), "1->2"
),
]:
result = []
def visit(node: Node) -> None:
result.append(node.val)
bt = BinaryTree(BinaryTree.build(nodes))
bt.in_order(visit)
result = "->".join([str(val) for val in result])
assert result == expected_result, "{} != {}".format(result, expected_result)
def test_Can_successfully_return_a_collection_from_an_inorder_traversal():
a = Node("A") # this assigns value to the node
b = Node("B")
c = Node("C")
d = Node("D")
e = Node("E")
tree = BinaryTree() # this makes the binary tree
tree.root = a
a.left = b
a.right = c
a.left.left = d
a.left.right = e
actual = tree.in_order()
expected = ["D", "B", "E", "A", "C"]
assert actual == expected