public void GetAllByCode_ShouldReturnNeededGoods_WhenCodeSend() { string testCode = "2233AGN"; var goods = new List <Good>() { new Good() { ID = 1, Code = testCode }, new Good() { ID = 2, Code = "2222AGN" }, new Good() { ID = 3, Code = testCode } }.AsQueryable(); var repositoryMock = new Mock <IExternalDbRepository <Good> >(); repositoryMock.Setup(x => x.All()).Returns(() => goods); GoodsService service = new GoodsService(repositoryMock.Object); List <Good> response = service.GetAllByCode(testCode).ToList(); Assert.AreEqual(response.Count, 2); Assert.AreEqual(response[0].Code, testCode); Assert.AreEqual(response[1].Code, testCode); repositoryMock.VerifyAll(); }