def test_append(self):
# test the append feature
print(msg.format(t="append"))
llst = lnk.lnklst()
node1 = lnk.node(1)
llst.append(node1)
self.assertEqual(llst.head, node1)
self.assertEqual(llst.tail, node1)
self.assertEqual(llst.size, 1)
node2 = lnk.node(2)
llst.append(node2)
self.assertEqual(llst.head, node1)
self.assertEqual(llst.tail, node2)
self.assertEqual(llst.size, 2)
print(hr)
def test_update_tail(self):
# test the tail tracking feature
print(msg.format(t="update tail"))
llst = lnk.lnklst()
node1 = lnk.node(1)
node2 = lnk.node(2)
# this is the basic hard coded method and is not to be used
# # since, this does not update the tail and the size of the linked list
llst.head = node1
llst.head.next = node2
# the tail is not updated and also the size
self.assertNotEqual(llst.tail, node2)
self.assertNotEqual(llst.size, 2)
# call the update_tail method
llst.update_tail()
self.assertEqual(llst.tail, node2)
print(hr)
def test_init(self):
# test constructor for linked list and node class
print(msg.format(t="constructor"))
llst = lnk.lnklst()
self.assertEqual(llst.head, None)
self.assertEqual(llst.tail, None)
self.assertEqual(llst.size, 0)
node = lnk.node(1)
self.assertEqual(node.data, 1)
self.assertEqual(node.next, None)
print(hr)
def test_insert_after_key(self):
# test the insert after key method
print(msg.format(t="insert after key"))
llst = lnk.lnklst()
node1 = lnk.node(1)
node2 = lnk.node(2)
node3 = lnk.node(3)
# this is the basic hard coded method and is not to be used
# # since, this does not update the tail and the size of the linked list
llst.head = node1
llst.head.next = node2
llst.head.next.next = node3
self.assertEqual(llst.head, node1)
# update_tail
llst.update_tail()
# call insert after key
llst.insert_after_key(2, 4)
self.assertEqual(llst.head, node1)
self.assertEqual(llst.head.next, node2)
self.assertEqual(llst.head.next.next.data, 4)
self.assertEqual(llst.tail, node3)
print(hr)
def test_prepend(self):
# test the prepend operation
print(msg.format(t="prepend"))
llst = lnk.lnklst()
node1 = lnk.node(1)
node2 = lnk.node(2)
node3 = lnk.node(3)
# this is the basic hard coded method and is not to be used
# # since, this does not update the tail and the size of the linked list
llst.head = node1
llst.head.next = node2
self.assertEqual(llst.head, node1)
# update_tail
llst.update_tail()
# call prepend
llst.prepend(node3)
self.assertEqual(llst.head, node3)
self.assertEqual(llst.head.next, node1)
self.assertEqual(llst.head.next.next, node2)
self.assertEqual(llst.tail, node2)
print(hr)
def test_delete(self):
# test the delete feature
print(msg.format(t="delete"))
llst = lnk.lnklst()
node1 = lnk.node(1)
node2 = lnk.node(2)
node3 = lnk.node(3)
node4 = lnk.node(4)
# append is already verified
llst.append(node1)
llst.append(node2)
llst.delete(2) # delete tail
self.assertEqual(llst.head, node1)
self.assertEqual(llst.tail, None) # test if tail is null
# run some more tests with delete
llst.append(node2)
llst.delete(1) # delete head
print(llst.head.data)
self.assertEqual(llst.head, node2)
self.assertEqual(llst.tail, None)
llst.delete(2)
self.assertEqual(llst.head, None)
self.assertEqual(llst.tail, None)
self.assertEqual(llst.size, 0)
# run some more tests with delete
llst.append(node1)
llst.append(node2)
llst.append(node3)
llst.append(node4)
llst.delete(2)
self.assertEqual(llst.head, node1)
self.assertEqual(llst.head.next, node3)
llst.delete(3)
self.assertEqual(llst.head.next, node4)
self.assertEqual(llst.tail, node4)
def test_lnklst_size(self):
# test to make sure the size calculation is correct
print(msg.format(t="linked list size"))
llst = lnk.lnklst()
node1 = lnk.node(1)
node2 = lnk.node(2)
node3 = lnk.node(3)
# this is the basic hard coded method and is not to be used
# # since, this does not update the tail and the size of the linked list
llst.head = node1
llst.head.next = node2
llst.head.next.next = node3
# the tail is not updated and also the size
self.assertNotEqual(llst.tail, node3)
self.assertNotEqual(llst.size, 2)
# call the update_tail method to track the tail
llst.update_tail()
# call the get_size() method to track size
llst.get_size()
self.assertEqual(llst.tail, node3)
self.assertEqual(llst.size, 3)
print(hr)