def test_cipher(self): cipher = AESCipher(None) message = ''.join( random.choice(string.ascii_uppercase + string.digits + string.ascii_lowercase) for _ in range(100)) key = ''.join( random.choice(string.ascii_uppercase + string.digits + string.ascii_lowercase) for _ in range(32)) # check cipher without key try: C = cipher.encrypt(message) self.assertFail() except Exception as err: self.assertEqual('Invalid key', str(err)) cipher.key = key C = cipher.encrypt(message) M = cipher.decrypt(C) self.assertEqual(M, message)