def test_pop_invalid():
ll = DoublyLinkedList()
with pytest.raises(AssertionError):
ll.pop(0)
ll.insert(0, 0)
for i in range(-ITERS // 2, ITERS // 2 + 1):
if i == 0: continue
with pytest.raises(AssertionError):
ll.pop(i)
def test_pop_only_element():
ll = DoublyLinkedList()
for data in [0, "a", 1.5, [], {}, DoublyLinkedList()]:
ll.insert(0, data)
assert (not ll.is_empty())
assert (id(ll.peek_head()) == id(ll.peek_tail()))
actual = ll.pop(0)
assert (ll.is_empty())
assert (actual == data)
def test_random_ops():
ll, arr = DoublyLinkedList(), []
for i in range(ITERS):
index = random.randrange(i + 1)
data = random.randrange(MAX_VAL)
ll.insert(index, data)
arr.insert(index, data)
assert (ll.to_array() == arr)
for i in range(ITERS):
index = random.randrange(ITERS)
actual = ll.peek(index)
expected = arr[index]
assert (actual == expected)
for i in range(ITERS, 0, -1):
index = random.randrange(i)
actual = arr.pop(index)
expected = ll.pop(index)
assert (actual == expected)
assert (ll.to_array() == arr)
assert (ll.is_empty() and len(arr) == 0)
