def test_delete_root():
bst = Bst()
bst.insert(8)
bst.insert(10)
bst.insert(4)
bst.insert(15)
bst.insert(7)
bst.insert(3)
bst.delete(8)
assert bst.contains(8) is False
assert bst._root == 10
def test_delete_root():
bst = Bst()
bst.insert(8)
bst.insert(10)
bst.insert(4)
bst.insert(15)
bst.insert(7)
bst.insert(3)
bst.delete(8)
assert bst.contains(8) is False
assert bst._root == 10
def test_delete_two_children():
bst = Bst()
bst.insert(8)
bst.insert(10)
bst.insert(4)
bst.insert(15)
bst.insert(7)
bst.insert(3)
bst.delete(4)
assert bst.contains(4) is False
assert bst._nodes[7] == [3, float('inf'), 8]
assert bst._nodes[3] == [None, float('inf'), 7]
assert bst._nodes[8] == [7, 10, None]
def test_delete_two_children():
bst = Bst()
bst.insert(8)
bst.insert(10)
bst.insert(4)
bst.insert(15)
bst.insert(7)
bst.insert(3)
bst.delete(4)
assert bst.contains(4) is False
assert bst._nodes[7] == [3, float("inf"), 8]
assert bst._nodes[3] == [None, float("inf"), 7]
assert bst._nodes[8] == [7, 10, None]
