def test_apply_once(self):
state = State(current_number=1)
op1 = Mock()
op1.operate = Mock(return_value=3)
state.apply(op1)
op1.operate.assert_called_with(1)
self.assertEqual(state.current_number, 3)
self.assertEqual(state.steps, [op1])
def test_clone_is_separate_instance(self):
state = State(current_number=3, steps=[2, 4, 8])
cloned_state = state.clone()
op1 = Mock()
op1.operate.side_effect = add_four
state.apply(op1)
self.assertEqual(cloned_state.current_number, 3)
self.assertEqual(cloned_state.steps, [2, 4, 8])
def test_apply_twice(self):
state = State()
op1 = Mock()
op1.operate.side_effect = add_four
state.apply(op1)
op1.operate.assert_called_with(0)
op2 = Mock()
op2.operate = Mock(return_value=7)
state.apply(op2)
op2.operate.assert_called_with(4)
self.assertEqual(state.current_number, 7)
self.assertEqual(state.steps, [op1, op2])
def test_positive_good_fraction(self):
state = State(current_number=1)
state.apply(DivideOperator(8))
self.assertEqual(state.current_number, 0.125)
def test_divide_positive(self):
state = State(current_number=50)
state.apply(DivideOperator(5))
self.assertEqual(state.current_number, 10)
def test_divide_negative(self):
state = State(current_number=24)
state.apply(DivideOperator(-3))
self.assertEqual(state.current_number, -8)
def test_multiply_positive(self):
state = State(current_number=6)
state.apply(MultiplyOperator(4))
self.assertEqual(state.current_number, 24)
def test_multiply_negative(self):
state = State(current_number=5)
state.apply(MultiplyOperator(-3))
self.assertEqual(state.current_number, -15)
def test_add_negative(self):
state = State(current_number=5)
state.apply(AddOperator(-8))
self.assertEqual(state.current_number, -3)
def test_add_positive(self):
state = State(current_number=10)
state.apply(AddOperator(5))
self.assertEqual(state.current_number, 15)
def test_add_zero(self):
state = State(current_number=2)
state.apply(AddOperator(0))
self.assertEqual(state.current_number, 2)
def test_negative_bad_fraction(self):
state = State(current_number=-1)
with self.assertRaises(ValueError):
state.apply(DivideOperator(16))
def test_positive_bad_fraction(self):
state = State(current_number=100)
with self.assertRaises(ValueError):
state.apply(DivideOperator(3))