public void GetStockTest() { //Arrange var mockUnitOfWork = new Mock <IUnitOfWork>(); var stock = new Stock() { Id = 1 }; mockUnitOfWork.Setup(un => un.StockRepository.Get(It.IsAny <Expression <Func <Stock, bool> > >(), null, It.IsAny <string>())).Returns(new List <Stock>() { stock }); IStockLogic stockLogic = new StockLogic(mockUnitOfWork.Object); var result = stockLogic.GetStock(stock.Id); Assert.Equal(result, stock); }