def test_remove_internal():
bst = make_tree()
pre = bst.preorder()
i = pre.index(Pair('g'))
bst.remove(Pair('g'))
pre = bst.preorder()
assert pre[i] == Pair('f')
def test_postorder():
bst = make_tree()
assert bst.postorder()[27] == Pair('W', 13)
def test_inorder():
bst = make_tree()
assert bst.inorder()[27] == Pair('T', 34)
def test_preorder():
bst = make_tree()
assert bst.preorder()[27] == Pair('R', 20)
def test_remove_leaf():
bst = make_tree()
bst.remove(Pair('z'))
pre = bst.preorder()
assert pre[-1] == Pair('w')
def test_tree_height():
bst = make_tree()
assert bst.height() == 11
def test_remove_root():
bst = make_tree()
bst.remove(Pair('C'))
pre = bst.preorder()
assert pre[0] == Pair('D')
def test_tree_size():
bst = make_tree()
assert bst.size() == 57
def test_rebalance():
bst = make_tree()
original_height = bst.height()
tree_data = bst.rebalance()
assert not original_height == bst.height()
def test_postorder():
bst = make_tree()
assert bst.postorder()[27] == 'W'
def test_inorder():
bst = make_tree()
assert bst.inorder()[27] == 'T'
def test_preorder():
bst = make_tree()
assert bst.preorder()[27] == 'R'
