public void Can_Get_All_Orders() { Mock <IRepository <Order> > mock = new Mock <IRepository <Order> >(); mock.Setup(m => m.GetAll()).Returns(new List <Order> { new Order { Id = 1, Name = "Order1" }, new Order { Id = 2, Name = "Order2" }, new Order { Id = 3, Name = "Order3" }, }); //BookRepository repository = new BookRepository(); TestHelps repository = new TestHelps(); var orders = repository.GetAllOrders(mock.Object).ToList(); Assert.AreEqual(3, orders.Count); }