Issue 3208 - Separate contentPolicy module into a parent and child part

lib/contentPolicy.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2015 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 15 matching lines @@
 
 let {Utils} = require("utils");
 let {Prefs} = require("prefs");
 let {FilterStorage} = require("filterStorage");
 let {BlockingFilter, WhitelistFilter, RegExpFilter} = require("filterClasses");
 let {defaultMatcher} = require("matcher");
 let {objectMouseEventHander} = require("objectTabs");
 let {ElemHide} = require("elemHide");
 
 /**
- * Randomly generated class name, to be applied to collapsed nodes.
- */
-let collapsedClass = "";
-
-/**
  * Public policy checking functions and auxiliary objects
  * @class
  */
 var Policy = exports.Policy =
 {
   /**
    * Set of explicitly supported content types
    * @type Set
    */
   contentTypes: new Set([
@@ skipping 26 matching lines @@
     for (let scheme of Prefs.whitelistschemes.toLowerCase().split(" "))
       this.whitelistSchemes.add(scheme);
 
     let messageManager = Cc["@mozilla.org/parentprocessmessagemanager;1"]
                            .getService(Ci.nsIMessageListenerManager)
                            .QueryInterface(Ci.nsIMessageBroadcaster);
     let handler = (message => this.shouldAllow(message.data));
     messageManager.addMessageListener("AdblockPlus:ShouldAllow", handler);
     onShutdown.add(() => messageManager.removeMessageListener("AdblockPlus:ShouldAllow", handler));
 
+    // Generate class identifier used to collapse nodes and register
+    // corresponding stylesheet.
+    let collapsedClass = "";
+    let offset = "a".charCodeAt(0);
+    for (let i = 0; i < 20; i++)
+      collapsedClass +=  String.fromCharCode(offset + Math.random() * 26);
+
     let handler2 = () => collapsedClass;
     messageManager.addMessageListener("AdblockPlus:GetCollapsedClass", handler2);
     onShutdown.add(() => messageManager.removeMessageListener("AdblockPlus:GetCollapsedClass", handler2));
-
-    // Generate class identifier used to collapse node and register corresponding
-    // stylesheet.
-    let offset = "a".charCodeAt(0);
-    for (let i = 0; i < 20; i++)
-      collapsedClass +=  String.fromCharCode(offset + Math.random() * 26);
 
     let collapseStyle = Services.io.newURI("data:text/css," +
         encodeURIComponent("." + collapsedClass +
         "{-moz-binding: url(chrome://global/content/bindings/general.xml#foobarbazdummy) !important;}"), null, null);
     Utils.styleService.loadAndRegisterSheet(collapseStyle, Ci.nsIStyleSheetService.USER_SHEET);
     onShutdown.add(() =>
     {
       Utils.styleService.unregisterSheet(collapseStyle, Ci.nsIStyleSheetService.USER_SHEET);
     });
   },
 
   /**
    * Checks whether a node should be blocked, hides it if necessary
-   * @param contentType {String}

[Thomas Greiner, 2015/11/11 16:52:33]

The documentation of the parameters is no longer accurate since they are no
longer passed separately.

However, the online documentation (see
http://usejsdoc.org/tags-param.html#parameters-with-properties) doesn't consider
object destructuring yet so the suggestion is to work around it by making up a
name for that object (see https://github.com/jsdoc3/jsdoc/issues/987).

FYI: Google's Closure Compiler opted for a different approach:
https://github.com/google/closure-compiler/issues/1114

[Wladimir Palant, 2015/11/11 17:43:26]

Done.

-   * @param location {String}
-   * @param frames {Object[]}
-   * @param isPrivate {Boolean}  true if the request belongs to a private browsing window
-   * @return {Object} An object containing properties block, collapse and hits
+   * @param {Object} data  request data
+   * @param {String} data.contentType
+   * @param {String} data.location
+   * @param {Object[]} data.frames
+   * @param {Boolean} data.isPrivate  true if the request belongs to a private browsing window
+   * @return {Object} An object containing properties allow, collapse and hits
    *                  indicating how this request should be handled.
    */
   shouldAllow: function({contentType, location, frames, isPrivate})
   {
     let hits = [];
 
     function addHit(frameIndex, contentType, docDomain, thirdParty, location, filter)
     {
       if (filter && !isPrivate)
         FilterStorage.increaseHitCount(filter);
@@ skipping 63 matching lines @@
     {
       match = location;
       location = match.text.replace(/^.*?#/, '#');
 
       if (!match.isActiveOnDomain(docDomain))
         return response(true, false);
 
       let exception = ElemHide.getException(match, docDomain);
       if (exception)
       {
         addHit(null, contentType, docDomain, false, location, exception);

[Thomas Greiner, 2015/11/11 16:52:33]

Detail: Isn't it more common to use `-1` for a non-existent index (e.g.
Array.prototype.indexOf`)? That'd allow you to use the common `... > -1` check
instead of `typeof ... == "number"` in child/contentPolicy.

[Wladimir Palant, 2015/11/11 17:43:25]

That's what I had initially but frameIndex: -1 doesn't correctly represent the
context here. In fact, the context isn't a frame, and also not some unknown
frame but the original DOM element - so not passing anything for this parameter
seems to be the best option for me. 

[Thomas Greiner, 2015/11/11 18:07:32]

Makes sense then, I agree.

         return response(true, false);
       }
 
       if (nogeneric && match.isGeneric())
         return response(true, false);
     }
 
     let thirdParty = (contentType == "ELEMHIDE" ? false : isThirdParty(location, docDomain));
     let collapse = false;
     if (!match && Prefs.enabled && RegExpFilter.typeMap.hasOwnProperty(contentType))
@@ skipping 202 matching lines @@
   if (!wnd || wnd.closed)
     return;
 
   if (entry.type == "OBJECT")
   {
     node.removeEventListener("mouseover", objectMouseEventHander, true);
     node.removeEventListener("mouseout", objectMouseEventHander, true);
   }
   Policy.processNode(wnd, node, entry.type, entry.location, true);
 }