def test_rotate_left_subtree_with_no_parent(self):
A = create_left_rotable_tree()
rotable_to_left_tree = AVL(A)
rotable_to_left_tree._left_rotate(rotable_to_left_tree.get_root())
B = rotable_to_left_tree.get_root()
a = B.get_right_child()
A = B.get_left_child()
b = A.get_right_child()
c = A.get_left_child()
expect(B.get_name()).to.be.equal('B')
expect(A.get_name()).to.be.equal('A')
expect(c.get_name()).to.be.equal('c')
expect(a.get_name()).to.be.equal('a')
expect(b.get_name()).to.be.equal('b')
expect(B.get_height()).to.be.equal(2)
expect(A.get_height()).to.be.equal(1)
expect(a.get_height()).to.be.equal(0)
expect(b.get_height()).to.be.equal(0)
expect(c.get_height()).to.be.equal(0)
expect(B.get_node_count()).to.be.equal(5)
expect(A.get_node_count()).to.be.equal(3)
expect(a.get_node_count()).to.be.equal(1)
expect(b.get_node_count()).to.be.equal(1)
expect(c.get_node_count()).to.be.equal(1)
def test_rotate_left_subtree_is_left_child_from_root(self):
A = create_left_rotable_tree()
root = Node(10, name='root')
root.set_left_child(A)
A.set_parent(root)
rotable_to_left_tree = AVL(root)
rotable_to_left_tree._left_rotate(
rotable_to_left_tree.get_root().get_left_child())
root = rotable_to_left_tree.get_root()
B = root.get_left_child()
a = B.get_right_child()
A = B.get_left_child()
b = A.get_right_child()
c = A.get_left_child()
expect(root.get_name()).to.be.equal('root')
expect(B.get_name()).to.be.equal('B')
expect(A.get_name()).to.be.equal('A')
expect(c.get_name()).to.be.equal('c')
expect(a.get_name()).to.be.equal('a')
expect(b.get_name()).to.be.equal('b')
expect(root.get_height()).to.be.equal(3)
expect(B.get_height()).to.be.equal(2)
expect(A.get_height()).to.be.equal(1)
expect(a.get_height()).to.be.equal(0)
expect(b.get_height()).to.be.equal(0)
expect(c.get_height()).to.be.equal(0)
expect(root.get_node_count()).to.be.equal(6)
expect(B.get_node_count()).to.be.equal(5)
expect(A.get_node_count()).to.be.equal(3)
expect(a.get_node_count()).to.be.equal(1)
expect(b.get_node_count()).to.be.equal(1)
expect(c.get_node_count()).to.be.equal(1)