Settings Router Refactor: Remove route.page legacy property.

chrome/browser/resources/settings/route.js

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 cr.define('settings', function() {
   /**
    * Class for navigable routes. May only be instantiated within this file.
    * @constructor
    * @param {string} path
    * @private
    */
   var Route = function(path) {
     this.path = path;
 
     /** @type {?settings.Route} */
     this.parent = null;
 
     // Below are all legacy properties to provide compatibility with the old
     // routing system. TODO(tommycli): Remove once routing refactor complete.
-    this.page = '';
     this.section = '';
     /** @type {!Array<string>} */ this.subpage = [];
   };
 
   Route.prototype = {
     /**
      * Returns a new Route instance that's a child of this route.
      * @param {string} path Extends this route's path if it doesn't contain a
      *     leading slash.
      * @param {string=} opt_subpageName
      * @return {!settings.Route}
      * @private
      */
     createChild: function(path, opt_subpageName) {
       assert(path);
 
       // |path| extends this route's path if it doesn't have a leading slash.
       // If it does have a leading slash, it's just set as the new route's URL.
       var newUrl = path[0] == '/' ? path : this.path + '/' + path;
 
       var route = new Route(newUrl);
       route.parent = this;
-      route.page = this.page;
       route.section = this.section;
       route.subpage = this.subpage.slice();  // Shallow copy.
 
       if (opt_subpageName)
         route.subpage.push(opt_subpageName);
 
       return route;
     },
 
     /**
@@ skipping 17 matching lines @@
      * @return {!settings.Route}
      * @private
      */
     createSection: function(path, section) {
       var route = this.createChild(path);
       route.section = section;
       return route;
     },
 
     /**
-     * Returns true if this route is a descendant of the parameter.
+     * Returns true if this route matches or is a descendant of the parameter.
      * @param {!settings.Route} route
      * @return {boolean}
      */
-    isDescendantOf: function(route) {
+    inSubtreeOf: function(route) {

[michaelpg, 2016/07/28 23:22:32]

bikeshedding: kind of a confusing name and concept. *generally* subtree means
"strict subtree". combining isDescendantOf and == is kinda awkward, IMO: this
function is used for two entirely different mutually exclusive reasons in the
app (checking the root) and the tests (checking the parent chain). see comments
below about .root.

[tommycli, 2016/07/29 00:03:35]

It's a confusing name. I changed it to isEqualOrInSubtreeOf.

I found it a useful concept since we need to check exactly this in settings_main
and settings_menu. Though for section expansion, we actually need to check
inStrictSubtreeOf, so that's kind of unfortunate...

I didn't want to do .root, because we also need to do this operation for
.section, and I wanted to consolidate those two concepts with the tree
structure.

Still open to more suggestions - I realize this is kind of confusing.

[michaelpg, 2016/07/29 00:21:11]

Like, that's my point: every use in this CL could be replaced by a function
"isRoot()", so why muddle things.
how about isEqualOrDescendantOf? maybe it's just me, but I have to translate
"subtree" in my head to "descendant of" because to me, the subtree of this route
means this route and *its* descendants.

+      if (this == route)
+        return true;
+
       for (var parent = this.parent; parent != null; parent = parent.parent) {
         if (route == parent)
           return true;
       }
 
       return false;
     },
   };
 
   // Abbreviated variable for easier definitions.
   var r = Route;
 
   // Root pages.
   r.BASIC = new Route('/');
-  r.BASIC.page = 'basic';
   r.ADVANCED = new Route('/advanced');
-  r.ADVANCED.page = 'advanced';
   r.ABOUT = new Route('/help');
-  r.ABOUT.page = 'about';
 
 <if expr="chromeos">
   r.INTERNET = r.BASIC.createSection('/internet', 'internet');
   r.NETWORK_DETAIL = r.INTERNET.createChild('/networkDetail', 'network-detail');
   r.KNOWN_NETWORKS = r.INTERNET.createChild('/knownNetworks', 'known-networks');
 </if>
 
   r.APPEARANCE = r.BASIC.createSection('/appearance', 'appearance');
   r.FONTS = r.APPEARANCE.createChild('/fonts', 'appearance-fonts');
 
@@ skipping 171 matching lines @@
 
     return Route[matchingKey];
   };
 
   return {
     Route: Route,
     navigateTo: navigateTo,
     getRouteForPath: getRouteForPath,
   };
 });