public void does_it_return_right_type() { //Arrange var processObject = new ProcessLogicClass(">(a,b)"); var truthTableObject = new TruthTable(processObject); List <string> list0 = new List <string>(); List <string> list1 = new List <string>(); truthTableObject.OutList0And1(truthTableObject.returnValuesEachLine(), truthTableObject.returnLogicResult(), out list0, out list1); //Act List <string> display0 = truthTableObject.FindRepetitionEnding(list0); //Assert Assert.IsInstanceOfType(display0, typeof(List <string>)); }