def test_modify_balance(self): account = Account('1', '1234', 100) account.add_balance(20) account.sub_balance(80) self.assertEqual(account.balance(), 40)
def test_modify_balance_return_error(self): with self.assertRaises(AccountWithoutBalanceError): account = Account('1', '1234', 100) self.assertIsNone(account.sub_balance(120))