class ProcessAndExecuteTest(unittest.TestCase):
def setUp(self):
patcher1 = patch.object(Registers, 'parse_instruction')
self.mock_parse = patcher1.start()
patcher2 = patch.object(Registers, 'is_true')
self.mock_is_true = patcher2.start()
patcher3 = patch.object(Registers, 'execute_instruction')
self.mock_execute = patcher3.start()
self.registers = Registers()
self.mock_parse.return_value = sentinel.code, sentinel.comparison
self.addCleanup(patcher1.stop)
self.addCleanup(patcher2.stop)
self.addCleanup(patcher3.stop)
def test_calls_parse_with_instruction(self):
self.registers.process_and_execute_instruction(sentinel.instruction)
self.mock_parse.assert_called_once_with(sentinel.instruction)
def test_calls_is_true_with_comparison(self):
self.registers.process_and_execute_instruction('instruction')
self.mock_is_true.assert_called_once_with(sentinel.comparison)
def test_calls_perform_instruction_only_if_is_true(self):
self.mock_is_true.return_value = True
self.registers.process_and_execute_instruction('instruction')
self.mock_execute.assert_called_once_with(sentinel.code)
self.mock_execute.reset_mock()
self.mock_is_true.return_value = False
self.registers.process_and_execute_instruction('instruction')
self.assertFalse(self.mock_execute.called)
