def test_clear_stack(self):
stack = Stack([9])
stack.clear()
self.assertEqual(0, stack.count())
self.assertEqual('', str(stack))
def test_create_empty_stack(self):
stack = Stack()
self.assertEqual('', str(stack))
def test_count_stack(self):
stack = Stack([4, 9])
self.assertEqual(2, stack.count())
def test_count_stack_empty_stack(self):
stack = Stack()
self.assertEqual(0, stack.count())
def test_peek_empty_stack(self):
stack = Stack()
with self.assertRaises(ValueError):
stack.peek()
self.assertEqual('', str(stack))
def test_peek_non_empty_stack(self):
stack = Stack([4, 9])
value = stack.peek()
self.assertEqual('4, 9', str(stack))
self.assertEqual('4', str(value))
def test_push_on_non_empty_stack(self):
stack = Stack([4, 9])
stack.push(6)
self.assertEqual('6, 4, 9', str(stack))
def test_push_on_empty_stack(self):
stack = Stack()
stack.push(6)
self.assertEqual('6', str(stack))
def test_create_stack_from_content(self):
stack = Stack([5, 8, 9])
self.assertEqual('5, 8, 9', str(stack))