public void Snack_machine_returns_money_with_highest_denomination_first()
        {
            SnackMachine snackMachine = new SnackMachine();
            snackMachine.LoadMoney(Dollar);

            snackMachine.InsertMoney(Quarter);
            snackMachine.InsertMoney(Quarter);
            snackMachine.InsertMoney(Quarter);
            snackMachine.InsertMoney(Quarter);
            snackMachine.ReturnMoney();

            snackMachine.MoneyInside.QuarterCount.Should().Be(4);
            snackMachine.MoneyInside.OneDollarCount.Should().Be(0);
        }
        public void After_purchase_change_is_returned()
        {
            var snackMachine = new SnackMachine();
            snackMachine.LoadSnacks(1, new SnackPile(Chocolate, 1, 0.5m));
            snackMachine.LoadMoney(TenCent * 10);

            snackMachine.InsertMoney(Dollar);
            snackMachine.BuySnack(1);

            snackMachine.MoneyInside.Amount.Should().Be(1.5m);
            snackMachine.MoneyInTransaction.Should().Be(0m);
        }