def test_get_len():
"""
can we get length of list
"""
ls = DoublyLinkedList()
ls.push_front(44)
ls.push_front(55)
expected = 2
actual = ls.get_len()
assert expected == actual
def test_peek_front():
"""
if we can peek a data from front
"""
ls = DoublyLinkedList()
ls.push_front(1)
ls.push_front(2)
expected = 2
actual = ls.peek_front()
assert actual == expected
def test_push_front():
"""
if we can push a data to head
"""
ls = DoublyLinkedList()
ls.push_front(34)
expected = 34
actual = ls.head.data
assert expected == actual
def some_doubly_linked_list():
# "{ cherries } -> <- { bananas } -> <-{ apples } -> NULL"
fruits = DoublyLinkedList()
fruits.insert("apples")
fruits.insert("bananas")
fruits.head.next.prev = fruits.head
fruits.insert("cherries")
fruits.head.next.prev = fruits.head
return fruits
def test_peek_at():
"""
can we peek data from a certain index
"""
ls = DoublyLinkedList()
ls.push_front(44)
ls.push_front(55)
ls.push_front(66)
expected = 55
actual = ls.peek_at(1)
assert actual == expected
def test_create_doubly_linked_list():
l = DoublyLinkedList()
def test_insert_to_nonempty_list():
fruits = DoublyLinkedList()
fruits.insert("apples")
fruits.insert("bananas")
assert fruits.head.value == "bananas"
assert fruits.head.next.value == "apples"
def test_linked_list_nodes():
fruits = DoublyLinkedList()
fruits.head = Node("apples")
fruits.head.next = Node("bananas")
assert fruits.head.next.value == "bananas"
def test_remove_at():
"""
can we remove at a certain point by index number
the ease of doubly linked list is here
"""
ls = DoublyLinkedList()
ls.push_front(1)
ls.push_front(2)
ls.push_front(55)
ls.push_front(6)
ls.remove_at(1)
expected = 2
actual = ls.peek_at(1)
assert actual == expected
def test_instantiation():
"""
if we can instantiate empty DoublyLinkedList
"""
assert DoublyLinkedList()