Esempio n. 1
0
 def test_insert_before(self):
     """
     Tests that a Node can add another Node before it
     """
     node = Node(1)
     node.insert_before(2)
     self.assertEqual(2, node.prev.value)
Esempio n. 2
0
 def test_delete_node(self):
     """
     Tests that a Node can delete itself
     """
     node = Node(1)
     node.insert_after(2)
     next = node.next
     node.insert_before(5)
     prev = node.prev
     node.delete()
     self.assertEqual(next.prev.value, 5)
     self.assertEqual(prev.next.value, 2)
Esempio n. 3
0
class DoublyLinkedListTests(unittest.TestCase):
    def setUp(self):
        self.node = Node(1)
        self.dll = DoublyLinkedList(self.node)

    def test_list_remove_from_tail(self):
        self.dll.remove_from_tail()
        self.assertIsNone(self.dll.head)
        self.assertIsNone(self.dll.tail)
        self.assertEqual(len(self.dll), 0)

        self.dll.add_to_tail(33)
        self.assertEqual(self.dll.head.value, 33)
        self.assertEqual(self.dll.tail.value, 33)
        self.assertEqual(len(self.dll), 1)
        self.assertEqual(self.dll.remove_from_tail(), 33)
        self.assertEqual(len(self.dll), 0)

        self.dll.add_to_tail(68)
        self.assertEqual(len(self.dll), 1)
        self.assertEqual(self.dll.remove_from_tail(), 68)
        self.assertEqual(len(self.dll), 0)

    def test_list_remove_from_head(self):
        self.dll.remove_from_head()
        self.assertIsNone(self.dll.head)
        self.assertIsNone(self.dll.tail)
        self.assertEqual(len(self.dll), 0)

        self.dll.add_to_head(2)
        self.assertEqual(self.dll.head.value, 2)
        self.assertEqual(self.dll.tail.value, 2)
        self.assertEqual(len(self.dll), 1)
        self.assertEqual(self.dll.remove_from_head(), 2)
        self.assertEqual(len(self.dll), 0)

        self.dll.add_to_head(55)
        self.assertEqual(len(self.dll), 1)
        self.assertEqual(self.dll.remove_from_head(), 55)
        self.assertEqual(len(self.dll), 0)

    def test_list_add_to_tail(self):
        self.assertEqual(self.dll.tail.value, 1)
        self.assertEqual(len(self.dll), 1)

        self.dll.add_to_tail(30)
        self.assertEqual(self.dll.tail.prev.value, 1)
        self.assertEqual(self.dll.tail.value, 30)
        self.assertEqual(len(self.dll), 2)

        self.dll.add_to_tail(20)
        self.assertEqual(self.dll.tail.prev.value, 30)
        self.assertEqual(self.dll.tail.value, 20)
        self.assertEqual(len(self.dll), 3)

    def test_node_delete(self):
        node_1 = Node(3)
        node_2 = Node(4)
        node_3 = Node(5)

        node_1.next = node_2
        node_2.next = node_3
        node_2.prev = node_1
        node_3.prev = node_2

        node_2.delete()

        self.assertEqual(node_1.next, node_3)
        self.assertEqual(node_3.prev, node_1)

    def test_node_insert_before(self):
        self.node.insert_before(0)
        self.assertEqual(self.node.prev.value, 0)

    def test_list_add_to_head(self):
        self.assertEqual(self.dll.head.value, 1)

        self.dll.add_to_head(10)
        self.assertEqual(self.dll.head.value, 10)
        self.assertEqual(self.dll.head.next.value, 1)
        self.assertEqual(len(self.dll), 2)

    def test_node_insert_after(self):
        self.node.insert_after(2)
        self.assertEqual(self.node.next.value, 2)

    def test_list_move_to_end(self):
        self.dll.add_to_head(40)
        self.assertEqual(self.dll.tail.value, 1)
        self.assertEqual(self.dll.head.value, 40)

        self.dll.move_to_end(self.dll.head)
        self.assertEqual(self.dll.tail.value, 40)
        self.assertEqual(self.dll.tail.prev.value, 1)
        self.assertEqual(len(self.dll), 2)

        self.dll.add_to_tail(4)
        self.dll.move_to_end(self.dll.head.next)
        self.assertEqual(self.dll.tail.value, 40)
        self.assertEqual(self.dll.tail.prev.value, 4)
        self.assertEqual(len(self.dll), 3)

    def test_list_move_to_front(self):
        self.dll.add_to_tail(3)
        self.assertEqual(self.dll.head.value, 1)
        self.assertEqual(self.dll.tail.value, 3)

        self.dll.move_to_front(self.dll.tail)
        self.assertEqual(self.dll.head.value, 3)
        self.assertEqual(self.dll.head.next.value, 1)
        self.assertEqual(len(self.dll), 2)

        self.dll.add_to_head(29)
        self.dll.move_to_front(self.dll.head.next)
        self.assertEqual(self.dll.head.value, 3)
        self.assertEqual(self.dll.head.next.value, 29)
        self.assertEqual(len(self.dll), 3)

    def test_list_delete(self):
        self.dll.delete(self.node)
        self.assertIsNone(self.dll.head)
        self.assertIsNone(self.dll.tail)
        self.assertEqual(len(self.dll), 0)

        self.dll.add_to_tail(1)
        self.dll.add_to_head(9)
        self.dll.add_to_tail(6)

        self.dll.delete(self.dll.head)
        self.assertEqual(self.dll.head.value, 1)
        self.assertEqual(self.dll.tail.value, 6)
        self.assertEqual(len(self.dll), 2)

        self.dll.delete(self.dll.head)
        self.assertEqual(self.dll.head.value, 6)
        self.assertEqual(self.dll.tail.value, 6)
        self.assertEqual(len(self.dll), 1)

    def test_get_max(self):
        self.assertEqual(self.dll.get_max(), 1)
        self.dll.add_to_tail(100)
        self.assertEqual(self.dll.get_max(), 100)
        self.dll.add_to_tail(55)
        self.assertEqual(self.dll.get_max(), 100)
        self.dll.add_to_tail(101)
        self.assertEqual(self.dll.get_max(), 101)