def setUp(self):
# []
self.empty_stack = Stack()
# [4]
self.unit_stack = Stack()
self.unit_stack.push(4)
# [3, 1, 2]
self.some_stack = Stack()
self.some_stack.push(3)
self.some_stack.push(1)
self.some_stack.push(2)
def test_equal_ok(self):
a = Stack()
self.assertEqual(a, self.empty_stack)
self.assertNotEqual(a, self.unit_stack)
self.assertNotEqual(a, self.some_stack)
a.push(4)
self.assertNotEqual(a, self.empty_stack)
self.assertEqual(a, self.unit_stack)
self.assertNotEqual(a, self.some_stack)
a.pop()
a.push(3)
a.push(1)
a.push(2)
self.assertNotEqual(a, self.empty_stack)
self.assertNotEqual(a, self.unit_stack)
self.assertEqual(a, self.some_stack)
