@memoize
def empty_function():
    global has_been_called
    has_been_called = True
    return 'empty_function'

class EcsCacheTest(unittest.TestCase):

    @memoize
    def empty_method(self):
        global has_been_called
        has_been_called = True
        return 'empty_method'

    def test_empty_functions(self):
        # test with an empty function
        # first call: we will use the real function
        self.assertEqual(empty_function(), 'empty_function')
        self.assertEqual(has_been_called, True)
        # Second call: we will use the cache
        self.assertEqual(empty_function(), 'empty_function')
        self.assertEqual(has_been_called, False)

        # test with an empty method
        # first call: we will use the real method
        self.assertEqual(self.empty_method(), 'empty_method')
        self.assertEqual(has_been_called, True)
        # Second call: we will use the cache
        self.assertEqual(self.empty_method(), 'empty_method')
        self.assertEqual(has_been_called, False)