public async Task GetBookByIdAsync_BookNotFound_ThrowsException() { const int ID = 1; var ex = await Assert.ThrowsExceptionAsync <HttpResponseException>(async() => await _model.GetBookByIdAsync(ID)); var expectedExceptionMessage = string.Format(BookModel.ErrorMessage.NOT_FOUND_FORMAT, ID); Assert.AreEqual(expectedExceptionMessage, ex.Message); Assert.AreEqual(HttpStatusCode.NOT_FOUND, ex.StatusCode); }