public void IsValidForRequestThrowsIfControllerContextIsNull() {
            // Arrange
            AcceptAjaxAttribute attr = new AcceptAjaxAttribute();

            // Act & assert
            ExceptionHelper.ExpectArgumentNullException(
                delegate {
                    attr.IsValidForRequest(null, null);
                }, "controllerContext");
        }
        public void IsValidForRequestReturnsTrueIfRequestIsAjaxRequest() {
            // Arrange
            AcceptAjaxAttribute attr = new AcceptAjaxAttribute();
            ControllerContext controllerContext = GetControllerContext(true /* isAjaxRequest */);

            // Act
            bool isValid = attr.IsValidForRequest(controllerContext, null);

            // Assert
            Assert.IsTrue(isValid);
        }