ShareKhan.domain.Portfolio.CalculateRealizedProfits C# (CSharp) Method

        public double CalculateRealizedProfits(ITransactionCollection statement, Instrument instrument)
        {
            ITransactionCollection instrumentSpecificTransaction = new TransactionCollection();
            foreach (Transaction transaction in statement.TransactionList)
            {
                if (transaction.Instrument == instrument)
                {
                    instrumentSpecificTransaction.Add(transaction);
                }
            }
            return instrumentSpecificTransaction.RealizedProfit().Profit.Value;
        }

 public void ShouldCalculateRealizedProfitsAtInstrumentLevelComplexCase()
 {
     Portfolio d = new Portfolio();
     TransactionCollection ts = new TransactionCollection();
     Stock relianceShare = new Stock(new Symbol("RIL"), new Price(10.00), "Reliance Industries");
     Stock infyShare = new Stock(new Symbol("INF"), new Price(100.00), "Infosys");
     ts.Add(new BuyTransaction(new DateTime(1999, 3, 20), relianceShare, 10, new Price(1200), 0, 0));
     ts.Add(new SellTransaction(new DateTime(1999, 5, 20), relianceShare, 5, new Price(1300), 0, 0));
     ts.Add(new BuyTransaction(new DateTime(1999, 8, 20), infyShare, 67, new Price(110), 0, 0));
     ts.Add(new SellTransaction(new DateTime(2000, 9, 20), infyShare, 63, new Price(101), 0, 0));
     Assert.AreEqual(500, d.CalculateRealizedProfits(ts, relianceShare));
     Assert.AreEqual(-567, d.CalculateRealizedProfits(ts, infyShare));
 }