public void GetApplicableGLassesByProductType_ShouldReturnNeededItems() { string productType = "windscreen"; var vehicle = new Vehicle() { MakeId = 1, ModelId = 1, BodyTypeId = 1, VehicleGlasses = new List <VehicleGlass>() { new VehicleGlass() { Id = 1, ProductType = productType }, new VehicleGlass() { Id = 2, ProductType = "test" }, new VehicleGlass() { Id = 3, ProductType = productType } } }; var repositoryMock = new Mock <IInternalDbRepository <Vehicle> >(); var service = new VehiclesService(repositoryMock.Object); var response = service.GetApplicableGLassesByProductType(vehicle, productType).ToList(); Assert.AreEqual(response.Count, 2); Assert.AreEqual(response[0].Id, 1); Assert.AreEqual(response[1].Id, 3); }