public void IsBookUpdated() { Book book = new Book(); List <int> litId = (from iter in bookBusiness.GetAllBooks() select iter.IdBook).ToList(); book.Title = Guid.NewGuid().ToString(); book.NameAuthor = Guid.NewGuid().ToString(); book.ISBN = Guid.NewGuid().ToString(); book.Quantity = Guid.NewGuid().GetHashCode(); book.YearOfIssue = Guid.NewGuid().GetHashCode(); book.IdBook = litId[0]; mockBookRepository.Setup(x => x.UpdataBook(book)).Returns(true); var result = bookBusiness.UpdataBook(book); Assert.IsTrue(result); }