public virtual void test_minus_CurrencyDouble_add()
        {
            CurrencyAmount      ca   = CurrencyAmount.of(Currency.AUD, 117);
            CurrencyAmount      cb   = CurrencyAmount.of(Currency.USD, 12);
            MultiCurrencyAmount mc1  = MultiCurrencyAmount.of(ca, cb);
            MultiCurrencyAmount test = mc1.minus(Currency.NZD, 3);

            assertMCA(test, ca, cb, CurrencyAmount.of(Currency.NZD, -3));
        }
        public virtual void test_minus_CurrencyDouble_null()
        {
            MultiCurrencyAmount test = MultiCurrencyAmount.of(CA1, CA2);

            assertThrowsIllegalArg(() => test.minus((Currency)null, 1));
        }