def test_return_postorder_traversal():
tree = BinarySearchTree()
tree.add(3)
tree.add(2)
tree.add(6)
actual = tree.post_order()
expected = [2,6,3]
assert actual == expected
def test_post_order():
tree = BinarySearchTree()
tree.add(10)
tree.add(5)
tree.add(15)
expected = [5, 15, 10]
actual = tree.post_order()
assert expected == actual
def test_post_order():
tree_stuff = BinarySearchTree()
tree_stuff.add(9)
tree_stuff.add(19)
tree_stuff.add(11)
tree_stuff.add(7)
tree_stuff.add(8)
actual = tree_stuff.post_order()
expected = [8, 7, 11, 19, 9]
assert actual == expected
def test_post_order():
"""
Can successfully return a collection from a preorder traversal
"""
tree = BinarySearchTree()
tree.add(6)
tree.add(5)
tree.add(7)
tree.add(8)
tree.add(3)
tree.add(4)
assert tree.post_order(tree.root) == [4, 3, 5, 8, 7, 6]
def test_post_order():
tree = BinarySearchTree()
tree.add(6)
tree.add(8)
tree.add(7)
tree.add(4)
tree.add(9)
tree.add(3)
expected = [3, 4, 7, 9, 8, 6]
actual = tree.post_order()
assert expected == actual
def test_postorder():
bst = BinarySearchTree()
bst.add(4)
bst.add(7)
bst.add(5)
bst.add(9)
bst.add(2)
bst.add(30)
bst.add(-1)
expected = [30, 9, 5, 7, -1, 2, 4]
actual = bst.post_order()
assert actual == expected
def test_post_order_empty():
tree = BinarySearchTree()
expected = []
actual = tree.post_order()
assert actual == expected
