Hiding and Expanding Menus

Question

I've created code for a menu system that can show / hide menus and submenus. Now I wonder if the structure of the code is good enough or if you find something that can be done better?

var initExpanders = function () {
 "use strict";
 function lsTest(){
 var test = 'localstoragetest';
 try {
 localStorage.setItem(test, test);
 localStorage.removeItem(test);
 return true;
 } catch(e) {
 return false;
 }
 }
 var IS_OPEN = 'open',
 localStorageisAvailable = lsTest();
 /**
 * Add the small arrows indicating an expander.
 *
 * @returns {string} to be inserted in document.
 */
 function expandButton() {
 return '<span class="indicator icon-down-open"></span>' +
 '<span class="indicator icon-up-open"></span>';
 }
 /**
 * Toggle state and of the expander.
 *
 * @param event The click event
 * @param expanderNode
 * @param bodyId
 */
 function toggleExpander(expanderNode, bodyId, from_history) {
 var bodyNode = expanderNode.find(bodyId);
 var speed = 200; //'fast'
 if (from_history == true) {
 //No sliding time if it was remembered from history
 speed = 0;
 }
 if (expanderNode.hasClass(IS_OPEN)){
 $.each(bodyNode, function() {
 $(this).slideUp(speed, function () {
 expanderNode.removeClass(IS_OPEN);
 storeOrRemoveHistory(expanderNode);
 });
 });
 } else {
 $.each(bodyNode, function() {
 $(this).slideDown(speed, function () {
 expanderNode.addClass(IS_OPEN);
 storeOrRemoveHistory(expanderNode);
 if ($(this).is('tr')) {
 $(this).css('display', 'table-row');
 }
 });
 });
 }
 }
 /**
 * Init localstorage history if localstorage available, trigger expand if any found
 * Saved by index of expanders at url.
 * @param node
 * @param titleNode
 * @param index
 */
 function initLocalStorageHistory(node, titleNode, index) {
 if(localStorageisAvailable) {
 $(node).attr('data-position', index);
 var dataPosition = window.location.href + index;
 if (localStorage.getItem(dataPosition)) {
 //Don't open anything if referrer is pren
 if($.urlParam('ref') != 'pren') {
 $(titleNode).trigger('click', true);
 }
 }
 }
 }
 $.urlParam = function(name){
 var results = new RegExp('[\?&]' + name + '=([^&#]*)').exec(window.location.href);
 if (results != null) {
 return results[1] || 0;
 } else return null;
 }
 /**
 *
 * Save state of expander to localstorage if available
 * @param expanderNode
 */
 function storeOrRemoveHistory(expanderNode) {
 if(localStorageisAvailable){
 var dataPosition = window.location.href + $(expanderNode).attr('data-position');
 if ($(expanderNode).hasClass(IS_OPEN)) {
 localStorage.setItem(dataPosition, 'open');
 } else {
 localStorage.removeItem(dataPosition);
 }
 }
 }
 /**
 * Enable all expanders.
 */
 $.each($('.expander'), function (i, node) {
 var titleNode = $(node).find('.expander-title:first');
 $(titleNode).append(expandButton());
 $(titleNode).click(function (event, from_history) {
 var clickTarget = $(event.currentTarget),
 expanderNode = clickTarget.closest('.expander'),
 from_history = from_history || false;
 if(window.location.href.indexOf("survey") > -1) {
 toggleExpander(expanderNode, '.expander-body', from_history);
 }
 else {
 toggleExpander(expanderNode, '.expander-body:first', from_history);
 }
 });
 initLocalStorageHistory(node, titleNode, i);
 });
}
$(document).ready(function () {
 "use strict";
 initExpanders();
});

Answer 1

I see a generic catch

catch(e)

If you make a spelling mistake, this will catch no method exception and always return false, very nasty and hidden bug. I suggest specifying exactly the expected exception.