public void TestMockAverageRating() { var mock = new Mock <CommentRepository>(); mock.Setup(a => a.GetComments(C.ProductId)).Returns(new List <Comment>() { C, CC }); Assert.AreEqual((C.Rating + CC.Rating) / 2.0, CommentRepository.AverageRating(mock.Object, C.ProductId), "Average should be equal"); }