def test_peek(self):
stacka = StackArray()
self.assertRaises(IndexError, stacka.peek)
stacka.num_items = 2
stacka.arr_list.arr = [1, 2]
stacka.arr_list.num_items = 2
self.assertEqual(stacka.peek(), 2)
stackl = StackLinked()
self.assertRaises(IndexError, stackl.peek)
stackl.top = stacks.Node(1, None)
stackl.num_items = 1
self.assertEqual(stackl.peek(), 1)
def test_push(self):
stack_1a = StackArray()
stack_1a.push(7)
stack_2a = StackArray()
stack_2a.arr_list.arr = [7, None]
stack_2a.arr_list.num_items = 1
stack_2a.num_items = 1
self.assertEqual(stack_1a, stack_2a)
stack_1l = StackLinked()
stack_1l.push(7)
stack_2l = StackLinked()
stack_2l.top = stacks.Node(7, None)
stack_2l.num_items = 1
self.assertEqual(stack_1l, stack_2l)