public void _金銭を投入して商品を受け取る_丁度の場合()
        {
            var ctx = new PurchaseContext(
                TestHelper.InitInfinityReservedChange(),
                TestHelper.InitInfinityItems(ItemRackState.CanNotPurchase)
                );

            Assert.That(ctx.CanPurchase(0), Is.False);

            ctx.ReceiveMoney(Money.Coin100);
            ctx.ReceiveMoney(Money.Coin10);
            ctx.ReceiveMoney(Money.Coin10);

            Assert.That(ctx.CanPurchase(0), Is.True, "should be purchased");

            var item = ctx.Purchase(0);

            Assert.That(item.Name, Is.EqualTo("Item0"));
            Assert.That(ctx.ReceivedTotal, Is.EqualTo(0));
        }