def test_delete(self):
ll = LinkedList(head=Node(1))
ll.insert_node(Node(5))
ll.delete_node(val=5)
assert str(ll) == '1->None'
ll.insert_node(Node(7))
ll.insert_node(Node(8))
assert str(ll) == '8->7->1->None'
ll.delete_node(1)
assert str(ll) == '8->7->None'
ll.delete_node(8)
ll.delete_node(7)
assert len(ll) == 0
def test_len(self):
ll = LinkedList(head=Node(1))
ll.insert_node(Node(5))
assert len(ll) == 2
def test_list(self):
ll = LinkedList(head=Node(1))
ll.insert_node(Node(5))
ll.insert_node(Node(7))
assert ll.tolist() == [7, 5, 1]
def test_print(self):
ll = LinkedList(head=Node(1))
ll.insert_node(Node(5))
assert str(ll) == '5->1->None'