def test_7(self):
""" test popleft() returns node removed from front (left) """
d = Dequeue()
n1 = Node(1)
n2 = Node(2)
d.append(n1)
d.append(n2)
self.assertEqual(d.popleft()._value, 1)
def test_12(self):
""" test peekleft() for return value """
d = Dequeue()
n1 = Node(1)
n2 = Node(2)
d.append(n1)
d.append(n2)
self.assertEqual(d.peekleft(), 1)
def test_2(self):
""" test append adds to end (right) """
d = Dequeue()
n1 = Node(1)
n2 = Node(2)
d.append(n1)
d.append(n2)
self.assertEqual(d.head._value, 1)
def test_9(self):
""" test length() returns length of list """
d = Dequeue()
n1 = Node(1)
n2 = Node(2)
n3 = Node(3)
d.append(n1)
d.append(n2)
d.append(n3)
self.assertEqual(d.length(), 3)
def test_8(self):
""" test appendleft maintains tail assignment """
d = Dequeue()
n1 = Node(1)
n2 = Node(2)
d.append(n2)
d.appendleft(n1)
self.assertEqual(d.tail._value, 2)
def test_3(self):
""" test appendleft adds to front (left) """
d = Dequeue()
n1 = Node(1)
n2 = Node(2)
d.append(n1)
d.appendleft(n2)
self.assertEqual(d.head._value, 2)
def test_4(self):
""" test popleft() removes node from front (left) """
d = Dequeue()
n1 = Node(1)
n2 = Node(2)
d.append(n1)
d.append(n2)
d.popleft()
self.assertEqual(d.head._value, 2)
def test_11(self):
""" test peek() for empty dequeue """
d = Dequeue()
self.assertEqual(d.peek(), None)
def test_6(self):
""" test popleft() returns exception if list is empty """
d = Dequeue()
self.assertEqual(d.popleft(), "Dequeue is empty")