public void お金を入れる_異常系(int input)
        {
            var insertedMoney = new Money(input);

            Assert.Throws(typeof(ArgumentException),
                () => venderMachine.InsertMoney(insertedMoney));
        }
        public void お金を入れる_正常系(int input, bool expected)
        {
            var insertedMoney = new Money(input);

            bool ret = venderMachine.InsertMoney(insertedMoney);

            Assert.AreEqual(expected, ret);
            Assert.AreEqual(input, venderMachine.Money);
        }
        public bool InsertMoney(Money money)
        {
            if (10 <= money.Amount && money.Amount <= 1000)
            {
                Money += money.Amount;
                return (JuiceStock.Price <= this.Money) && JuiceStock.Stock > 0;
            }
            else
            {
                throw new ArgumentException();

            }
        }
        public void 払い戻しの確認()
        {
            var insertedMoney = new Money(100);

            venderMachine.InsertMoney(insertedMoney);

            int ret = venderMachine.PayBack();

            Assert.AreEqual(0, venderMachine.Money);
            Assert.AreEqual(100, ret);
        }