Issue 3869 - Use the new FilterNotifier API

messageResponder.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2016 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 44 matching lines @@
   var changeListeners = new global.ext.PageMap();
   var listenedPreferences = [];
   var listenedFilterChanges = [];
   var messageTypes = {
     "app": "app.listen",
     "filter": "filters.listen",
     "pref": "prefs.listen",
     "subscription": "subscriptions.listen"
   };
 
   function sendMessage(type, action)

[Sebastian Noack, 2016/03/23 23:15:51]

Sorry for refactoring sendMessage() again, but with onFilterChange gone, it made
sense to move the filter/subscription conversion in here. Also "args" are now
accepted as variable arguments instead of an array.

   {
     var pages = changeListeners.keys();
     if (pages.length == 0)
       return;
 
     var args = [];
     for (var i = 2; i < arguments.length; i++)
     {
       var arg = arguments[i];
       if (arg instanceof Subscription)
@@ skipping 13 matching lines @@
       {
         page.sendMessage({
           type: messageTypes[type],
           action: action,
           args: args
         });
       }
     }
   }
 
   function addFilterListeners(type, actions)

[Sebastian Noack, 2016/03/23 23:15:51]

Same pattern as for Prefs.on(), the first UI that listens for a particular
preference causes a listener for that preference to be added, which then
propagates the notifications to all pages that listen for it.

   {
     actions.forEach(function(action)
     {
       var name;
       if (type == "filter" && action == "loaded")
         name = "load";
       else
         name = type + "." + action;
 
       if (listenedFilterChanges.indexOf(name) == -1)
       {
         listenedFilterChanges.push(name);
         FilterNotifier.on(name, function()
         {
           var args = [type, action];
           for (var i = 0; i < arguments.length; i++)

[Sebastian Noack, 2016/03/23 23:15:51]

For the record, simply passing the arguments object to sendMessage() or whatever
function would cause a deoptimization in V8. So we need a loop to turn it into
an array anyway.

             args.push(arguments[i]);
           sendMessage.apply(null, args);
         });
       }
     });
   }
 
   function getListenerFilters(page)
   {
     var listenerFilters = changeListeners.get(page);
@@ skipping 52 matching lines @@
             devToolsPanel: info.platform == "chromium",
             safariContentBlocker: "safari" in global
                 && "extension" in global.safari
                 && "setContentBlocker" in global.safari.extension
           });
         }
         else
           callback(null);
         break;
       case "app.listen":
-        var listenerFilters = getListenerFilters(sender.page);
-        if (message.filter)
-          listenerFilters.app = message.filter;
-        else
-          delete listenerFilters.app;
+        getListenerFilters(sender.page).app = message.filter;
         break;
       case "app.open":
         if (message.what == "options")
           ext.showOptions();
         break;
       case "filters.add":
         var result = require("filterValidation").parseFilter(message.text);
         var errors = [];
         if (result.error)
           errors.push(result.error.toString());
@@ skipping 76 matching lines @@
             var filter = subscription.filters[j];
             if (/^@@\|\|([^\/:]+)\^\$document$/.test(filter.text))
               continue;
 
             if (!(filter.text in seenFilter))
               FilterStorage.removeFilter(filter);
           }
         }
         break;
       case "filters.listen":
-        var listenerFilters = getListenerFilters(sender.page);
-        if (message.filter)
-        {
-          addFilterListeners("filter", message.filter);
-          listenerFilters.filter = message.filter;
-        }
-        else
-          delete listenerFilters.filter;
+        getListenerFilters(sender.page).filter = message.filter;
+        addFilterListeners("filter", message.filter);
         break;
       case "filters.remove":
         var filter = Filter.fromText(message.text);
         var subscription = null;
         if (message.subscriptionUrl)
           subscription = Subscription.fromURL(message.subscriptionUrl);
 
         if (!subscription)
           FilterStorage.removeFilter(filter);
         else
           FilterStorage.removeFilter(filter, subscription, message.index);
         break;
       case "prefs.get":
         callback(Prefs[message.key]);
         break;
       case "prefs.listen":
-        var listenerFilters = getListenerFilters(sender.page);
-        if (message.filter)
-        {
-          message.filter.forEach(function(preference)
-          {
-            if (listenedPreferences.indexOf(preference) == -1)
+        getListenerFilters(sender.page).pref = message.filter;
+        message.filter.forEach(function(preference)
+        {
+          if (listenedPreferences.indexOf(preference) == -1)
+          {
+            listenedPreferences.push(preference);
+            Prefs.on(preference, function()
             {
-              listenedPreferences.push(preference);
-              Prefs.on(preference, function()
-              {
-                sendMessage("pref", preference, Prefs[preference]);
-              });
-            }
-          });
-          listenerFilters.pref = message.filter;
-        }
-        else
-          delete listenerFilters.pref;
+              sendMessage("pref", preference, Prefs[preference]);
+            });
+          }
+        });
         break;
       case "prefs.toggle":
         if (message.key == "notifications_ignoredcategories")
           NotificationStorage.toggleIgnoreCategory("*");
         else
           Prefs[message.key] = !Prefs[message.key];
         break;
       case "subscriptions.add":
         var subscription = Subscription.fromURL(message.url);
         if ("title" in message)
@@ skipping 24 matching lines @@
             return false;
           if (s instanceof DownloadableSubscription && message.downloadable)
             return true;
           if (s instanceof SpecialSubscription && message.special)
             return true;
           return false;
         });
         callback(subscriptions.map(convertSubscription));
         break;
       case "subscriptions.listen":
-        var listenerFilters = getListenerFilters(sender.page);
-        if (message.filter)
-        {
-          addFilterListeners("subscription", message.filter);
-          listenerFilters.subscription = message.filter;
-        }
-        else
-          delete listenerFilters.subscription;
+        getListenerFilters(sender.page).subscription = message.filter;
+        addFilterListeners("subscription", message.filter);
         break;
       case "subscriptions.remove":
         var subscription = Subscription.fromURL(message.url);
         if (subscription.url in FilterStorage.knownSubscriptions)
           FilterStorage.removeSubscription(subscription);
         break;
       case "subscriptions.toggle":
         var subscription = Subscription.fromURL(message.url);
         if (subscription.url in FilterStorage.knownSubscriptions)
         {
@@ skipping 21 matching lines @@
           if (subscription instanceof DownloadableSubscription)
             Synchronizer.execute(subscription, true);
         }
         break;
       case "subscriptions.isDownloading":
         callback(Synchronizer.isExecuting(message.url));
         break;
     }
   });
 })(this);