public void ReturnSuccessStateTransferWhenCallCredit()
        {
            uint amountToBeDebited = 100;
            var  creditBankAccount = new CreditBankAccount(300);

            var actualState = creditBankAccount.Credit(amountToBeDebited);

            actualState.ShouldBe(StateTransfer.Success);
        }
        public void AddAmountToSoldWhenCallCredit()
        {
            uint expectedSold      = 400;
            uint amountToBeDebited = 100;
            var  creditBankAccount = new CreditBankAccount(300);

            creditBankAccount.Credit(amountToBeDebited);

            creditBankAccount.Sold.ShouldBe(expectedSold);
        }