InstaTax.Core.DomainObjects.OtherIncomes.CalculateTotalAmount C# (CSharp) Метод

        public double CalculateTotalAmount()
        {
            return otherIncomeItems.Sum(a => a.Amount);
        }

 public void ShouldGetTotalAmountForOtherIncomeItems()
 {
     OtherIncomes ois = new OtherIncomes();
     ois.Add(new OtherIncomeItem("Interet", 12000.0));
     ois.Add(new OtherIncomeItem("Rental", 12000.0));
     Assert.AreEqual(24000.00m, ois.CalculateTotalAmount());
 }