def test_get_node_by_index(self):
node1 = LinkedListNode("node 1")
node2 = LinkedListNode("node 2")
my_linked_list = LinkedList()
my_linked_list.add_first(node1)
my_linked_list.add_last(node2)
print(my_linked_list)
with self.assertRaises(IndexError):
my_linked_list.get_node_by_index(2)
self.assertEqual(
my_linked_list.get_node_by_index(0).node_value, 'node 1')
self.assertEqual(
my_linked_list.get_node_by_index(1).node_value, 'node 2')
def test_delete_nodes(self):
node1 = LinkedListNode("node 1")
node2 = LinkedListNode("node 2")
node3 = LinkedListNode("node 3")
node4 = LinkedListNode("node 4")
my_linked_list = LinkedList()
my_linked_list.add_first(node1)
my_linked_list.add_last(node2)
my_linked_list.add_last(node3)
my_linked_list.add_last(node4)
my_linked_list.delete_node(node1)
self.assertEqual(my_linked_list.length, 3)
self.assertEqual(my_linked_list.head, node2)
my_linked_list.delete_node(node3)
self.assertEqual(my_linked_list.length, 2)
self.assertEqual(my_linked_list.get_node_by_index(1), node4)
my_linked_list.delete_node(node4)
self.assertEqual(my_linked_list.length, 1)
self.assertEqual(my_linked_list.head, node2)
self.assertEqual(my_linked_list.tail, node2)
with self.assertRaises(ValueError):
my_linked_list.delete_node(node4)
my_linked_list.delete_node(node2)
self.assertEqual(my_linked_list.length, 0)
self.assertEqual(my_linked_list.head, None)
self.assertEqual(my_linked_list.tail, None)
def test_iteration_of_nodes(self):
node1 = LinkedListNode("node 1")
node2 = LinkedListNode("node 2")
node3 = LinkedListNode("node 3")
my_linked_list = LinkedList()
my_linked_list.add_first(node1)
my_linked_list.add_last(node2)
my_linked_list.add_last(node3)
counter = 0
for node in my_linked_list:
self.assertEqual(node, my_linked_list.get_node_by_index(counter))
counter += 1
def test_add_node_after(self):
node1 = LinkedListNode("node 1")
node2 = LinkedListNode("node 2")
node3 = LinkedListNode("node 3")
node4 = LinkedListNode("node 4")
my_linked_list = LinkedList()
my_linked_list.add_first(node1)
my_linked_list.add_node_after(node1, node2)
self.assertEqual(my_linked_list.head.node_value, 'node 1')
self.assertEqual(
my_linked_list.get_node_by_index(1).node_value, 'node 2')
self.assertEqual(my_linked_list.length, 2)
with self.assertRaises(ValueError):
my_linked_list.add_node_after(node3, node4)
my_linked_list.add_node_after(node2, node3)
self.assertEqual(
my_linked_list.get_node_by_index(1).node_value, 'node 2')
self.assertEqual(
my_linked_list.get_node_by_index(2).node_value, 'node 3')
self.assertEqual(my_linked_list.tail.node_value, 'node 3')
self.assertEqual(my_linked_list.length, 3)
print(my_linked_list)
