def create_bst_2():
btree = BST()
vals = [10, 5, 15, 2, 7, 20, 6, 8, 17]
for val in vals:
btree.insert(val=val)
return btree
def test_insert_second_value_greater_than_root():
"""When inserting a value larger than the root, it should go in a new
node as right_child to root in a tree with only root."""
btree = BST()
btree.insert(val=3)
btree.insert(val=10)
assert btree.root.right_child is not None
assert btree.root.right_child.val == 10
def test_insert_second_value_smaller_than_root():
"""When inserting a value smaller than the root, it should go in a new
node as left_child to root in a tree with only root."""
btree = BST()
btree.insert(val=3)
btree.insert(val=2)
assert btree.root.left_child is not None
assert btree.root.right_child is None
assert btree.root.left_child.val == 2
def test_insert_first_value():
"""First insertion should set root to that node, and that node
should have no parents or children."""
btree = BST()
btree.insert(val=7)
assert btree.root is not None
assert btree.root.val == 7
assert btree.root.parent is None
assert btree.root.left_child is None
assert btree.root.right_child is None
