public void CombineMovieListsTest() { var movieList1 = new List <Movie>() { new Movie() { Title = "Unique1", Rating = "5.5", Id = "2" }, new Movie() { Title = "Unique2", Rating = "8.9", Id = "0" }, new Movie() { Title = "ShouldBeOnlyOne", Rating = "6.5", Id = "1" }, }; var movieList2 = new List <Movie>() { new Movie() { Title = "Unique3", Rating = "5.5", Id = "2" }, new Movie() { Title = "Unique4", Rating = "8.9", Id = "0" }, new Movie() { Title = "ShouldBeOnlyOne", Rating = "6.5", Id = "1" }, }; var service = new MovieService(); var expected = 5; var actual = service.CombineMovieListsWithoutDuplicates(movieList1, movieList2).Count; Assert.AreEqual(expected, actual); }