public void CalculateTotalBuys_3Buys1Sell_Returns3() { var stocks = new List <Stock> { new Stock { Recommendation = Recommendation.Buy }, new Stock { Recommendation = Recommendation.Sell }, new Stock { Recommendation = Recommendation.Buy }, new Stock { Recommendation = Recommendation.Buy }, }; var target = new SummaryCalculator(); var actual = target.CalculateTotalBuys(stocks); var expected = 3; Assert.AreEqual(expected, actual); }