Issue 4871 - Start using ESLint for adblockplusui

background.js

Index: background.js
diff --git a/background.js b/background.js
index 5ef6f0d844267fa976b37e602c863c64a9f46100..6dbb745b89e9ed32152db8746b707423f11beb49 100644
--- a/background.js
+++ b/background.js
@@ -15,37 +15,38 @@
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-(function(global)
+"use strict";
+
 {
   function EventEmitter()
   {
     this._listeners = Object.create(null);
   }
   EventEmitter.prototype = {
-    on: function(name, listener)
+    on(name, listener)
     {
       if (name in this._listeners)
         this._listeners[name].push(listener);
       else
         this._listeners[name] = [listener];
     },
-    off: function(name, listener)
+    off(name, listener)
     {
-      var listeners = this._listeners[name];
+      let listeners = this._listeners[name];
       if (listeners)
       {
-        var idx = listeners.indexOf(listener);
+        let idx = listeners.indexOf(listener);
         if (idx != -1)
           listeners.splice(idx, 1);
       }
     },
-    emit: function(name)
+    emit(name, ...args)
     {
-      var listeners = this._listeners[name];
+      let listeners = this._listeners[name];
       if (listeners)
       {
-        for (var i = 0; i < listeners.length; i++)
-          listeners[i].apply(null, Array.prototype.slice.call(arguments, 1));
+        for (let i = 0; i < listeners.length; i++)
+          listeners[i](...args);
       }
     }
   };
@@ -54,17 +55,17 @@
   {
     if (window.location.search)
     {
-      var params = window.location.search.substr(1).split("&");
-      for (var i = 0; i < params.length; i++)
+      let params = window.location.search.substr(1).split("&");
+      for (let i = 0; i < params.length; i++)
       {
-        var parts = params[i].split("=", 2);
+        let parts = params[i].split("=", 2);
         if (parts.length == 2 && parts[0] in data)
           data[parts[0]] = decodeURIComponent(parts[1]);
       }
     }
   }
 
-  var params = {
+  let params = {
     blockedURLs: "",
     filterlistsReinitialized: false,
     addSubscription: false,
@@ -74,15 +75,15 @@
   };
   updateFromURL(params);
 
-  var modules = {};
-  global.require = function(module)
+  let modules = {};
+  window.require = function(module)
   {
     return modules[module];
   };
 
   modules.utils = {
     Utils: {
-      getDocLink: function(link)
+      getDocLink(link)
       {
         return "https://adblockplus.org/redirect?link=" + encodeURIComponent(link);
       },
@@ -94,21 +95,21 @@
   };
 
   modules.prefs = {Prefs: new EventEmitter()};
-  var prefs = {
+  let prefs = {
     notifications_ignoredcategories: (params.showNotificationUI) ? ["*"] : [],
     notifications_showui: params.showNotificationUI,
     shouldShowBlockElementMenu: true,
     show_devtools_panel: true,
     subscriptions_exceptionsurl: "https://easylist-downloads.adblockplus.org/exceptionrules.txt"
   };
-  Object.keys(prefs).forEach(function(key)
+  Object.keys(prefs).forEach(key =>
   {
     Object.defineProperty(modules.prefs.Prefs, key, {
-      get: function()
+      get()
       {
         return prefs[key];
       },
-      set: function(value)
+      set(value)
       {
         prefs[key] = value;
         modules.prefs.Prefs.emit(key);
@@ -118,10 +119,10 @@
 
   modules.notification = {
     Notification: {
-      toggleIgnoreCategory: function(category)
+      toggleIgnoreCategory(category)
       {
-        var categories = prefs.notifications_ignoredcategories;
-        var index = categories.indexOf(category);
+        let categories = prefs.notifications_ignoredcategories;
+        let index = categories.indexOf(category);
         if (index == -1)
           categories.push(category);
         else
@@ -131,6 +132,7 @@
     }
   };
 
+  /* eslint-disable object-shorthand */

[Sebastian Noack, 2017/02/21 12:21:20]

Note that the object-shorthand rule has an ignoreConstructors option, in order
to ignore capitalized properties.

Alternatively, we could just define the constructur beforehand, as we did in at
least one other place already, in order to avoid triggering this rule:

  function Subscription()
  {
    ...
  }
  modules.subscriptionClasses = {
    Subscription,
    ...
  };

Not sure which I prefer. But either option seems better than the inline
configuration.

[kzar, 2017/02/23 11:10:22]

Done.

   modules.subscriptionClasses = {
     Subscription: function(url)
     {
@@ -155,10 +157,11 @@
 
     if (/^https?:\/\//.test(url))
       return new modules.subscriptionClasses.Subscription(url);
-    else
-      return new modules.subscriptionClasses.SpecialSubscription(url);
+    return new modules.subscriptionClasses.SpecialSubscription(url);
   };
-  modules.subscriptionClasses.DownloadableSubscription = modules.subscriptionClasses.Subscription;
+  /* eslint-enable object-shorthand */
+  modules.subscriptionClasses.DownloadableSubscription =
+    modules.subscriptionClasses.Subscription;
 
   modules.subscriptionClasses.Subscription.prototype =
   {
@@ -178,7 +181,8 @@
     set lastDownload(value)
     {
       this._lastDownload = value;
-      modules.filterNotifier.FilterNotifier.emit("subscription.lastDownload", this);
+      modules.filterNotifier.FilterNotifier.emit("subscription.lastDownload",
+                                                 this);
     }
   };
 
@@ -187,9 +191,13 @@
     FilterStorage: {
       get subscriptions()
       {
-        var subscriptions = [];
-        for (var url in modules.filterStorage.FilterStorage.knownSubscriptions)
-          subscriptions.push(modules.filterStorage.FilterStorage.knownSubscriptions[url]);
+        let subscriptions = [];
+        for (let url in modules.filterStorage.FilterStorage.knownSubscriptions)
+        {
+          subscriptions.push(
+            modules.filterStorage.FilterStorage.knownSubscriptions[url]
+          );
+        }
         return subscriptions;
       },
 
@@ -198,27 +206,34 @@
         return knownSubscriptions;
       },
 
-      addSubscription: function(subscription)
+      addSubscription(subscription)
       {
-        if (!(subscription.url in modules.filterStorage.FilterStorage.knownSubscriptions))
+        let {fromURL} = modules.subscriptionClasses.Subscription;
+        let {FilterStorage} = modules.filterStorage;
+
+        if (!(subscription.url in FilterStorage.knownSubscriptions))
         {
-          knownSubscriptions[subscription.url] = modules.subscriptionClasses.Subscription.fromURL(subscription.url);
-          modules.filterNotifier.FilterNotifier.emit("subscription.added", subscription);
+          knownSubscriptions[subscription.url] = fromURL(subscription.url);
+          modules.filterNotifier.FilterNotifier.emit("subscription.added",
+                                                     subscription);
         }
       },
 
-      removeSubscription: function(subscription)
+      removeSubscription(subscription)
       {
-        if (subscription.url in modules.filterStorage.FilterStorage.knownSubscriptions)
+        let {FilterStorage} = modules.filterStorage;
+
+        if (subscription.url in FilterStorage.knownSubscriptions)
         {
           delete knownSubscriptions[subscription.url];
-          modules.filterNotifier.FilterNotifier.emit("subscription.removed", subscription);
+          modules.filterNotifier.FilterNotifier.emit("subscription.removed",
+                                                     subscription);
         }
       },
 
-      addFilter: function(filter)
+      addFilter(filter)
       {
-        for (var i = 0; i < customSubscription.filters.length; i++)
+        for (let i = 0; i < customSubscription.filters.length; i++)
         {
           if (customSubscription.filters[i].text == filter.text)
             return;
@@ -227,14 +242,15 @@
         modules.filterNotifier.FilterNotifier.emit("filter.added", filter);
       },
 
-      removeFilter: function(filter)
+      removeFilter(filter)
       {
-        for (var i = 0; i < customSubscription.filters.length; i++)
+        for (let i = 0; i < customSubscription.filters.length; i++)
         {
           if (customSubscription.filters[i].text == filter.text)
           {
             customSubscription.filters.splice(i, 1);
-            modules.filterNotifier.FilterNotifier.emit("filter.removed", filter);
+            modules.filterNotifier.FilterNotifier.emit("filter.removed",
+                                                       filter);
             return;
           }
         }
@@ -242,36 +258,38 @@
     }
   };
 
+  /* eslint-disable object-shorthand */
   modules.filterClasses = {
-    BlockingFilter: function() {},
+    BlockingFilter: () => {},
     Filter: function(text)
     {
       this.text = text;
       this.disabled = false;
     },
-    RegExpFilter: function() {}
+    RegExpFilter: () => {}
   };
+  /* eslint-enable object-shorthand */
   modules.filterClasses.Filter.fromText = function(text)
   {
     return new modules.filterClasses.Filter(text);
   };
   modules.filterClasses.RegExpFilter.typeMap = Object.create(null);
 
-  modules.filterValidation = 
+  modules.filterValidation =
   {
-    parseFilter: function(text)
+    parseFilter(text)
     {
       if (params.filterError)
         return {error: "Invalid filter"};
       return {filter: modules.filterClasses.Filter.fromText(text)};
     },
-    parseFilters: function(text)
+    parseFilters(text)
     {
       if (params.filterError)
         return {errors: ["Invalid filter"]};
       return {
         filters: text.split("\n")
-          .filter(function(filter) {return !!filter;})
+          .filter(filter => !!filter)
           .map(modules.filterClasses.Filter.fromText),
         errors: []
       };
@@ -281,19 +299,19 @@
   modules.synchronizer = {
     Synchronizer: {
       _downloading: false,
-      execute: function(subscription, manual) 
+      execute(subscription, manual)
       {
         modules.synchronizer.Synchronizer._downloading = true;
         modules.filterNotifier.FilterNotifier.emit(
           "subscription.downloading", subscription
         );
-        setTimeout(function()
+        setTimeout(() =>
         {
           modules.synchronizer.Synchronizer._downloading = false;
           subscription.lastDownload = Date.now() / 1000;
         }, 500);
       },
-      isExecuting: function(url)
+      isExecuting(url)
       {
         return modules.synchronizer.Synchronizer._downloading;
       }
@@ -302,13 +320,12 @@
 
   modules.matcher = {
     defaultMatcher: {
-      matchesAny: function(url, requestType, docDomain, thirdParty)
+      matchesAny(url, requestType, docDomain, thirdParty)
       {
-        var blocked = params.blockedURLs.split(",");
+        let blocked = params.blockedURLs.split(",");
         if (blocked.indexOf(url) >= 0)
           return new modules.filterClasses.BlockingFilter();
-        else
-          return null;
+        return null;
       }
     }
   };
@@ -344,7 +361,7 @@
     if (event.data.type != "message")
       return;
     let message = event.data.payload;
-    let messageId = event.data.messageId;
+    let {messageId} = event.data;
     let sender = {
       page: new ext.Page(event.source)
     };
@@ -353,12 +370,12 @@
     if (!listeners)
       return;
 
-    function reply(message)
+    function reply(responseMessage)
     {
       event.source.postMessage({
         type: "response",
-        messageId: messageId,
-        payload: message
+        messageId,
+        payload: responseMessage
       }, "*");
     }
 
@@ -369,29 +386,28 @@
       {
         response.then(
           reply,
-          reason => {
+          reason =>
+          {
             console.error(reason);
             reply(undefined);
           }
         );
       }
       else if (typeof response != "undefined")
-      {
         reply(response);
-      }
     }
   });
 
-  global.Services = {
+  window.Services = {
     vc: {
-      compare: function(v1, v2)
+      compare(v1, v2)
       {
         return parseFloat(v1) - parseFloat(v2);
       }
     }
   };
 
-  var filters = [
+  let filters = [
     "@@||alternate.de^$document",
     "@@||der.postillion.com^$document",
     "@@||taz.de^$document",
@@ -413,24 +429,27 @@
     "###ad-bereich2-08",
     "###ad-bereich2-skyscrapper"
   ];
-  var knownFilters = filters.map(modules.filterClasses.Filter.fromText);
+  let knownFilters = filters.map(modules.filterClasses.Filter.fromText);
 
-  var subscriptions = [
+  let subscriptions = [
     "https://easylist-downloads.adblockplus.org/easylistgermany+easylist.txt",
     "https://easylist-downloads.adblockplus.org/exceptionrules.txt",
     "https://easylist-downloads.adblockplus.org/fanboy-social.txt",
     "~user~786254"
   ];
-  var knownSubscriptions = Object.create(null);
-  for (var subscriptionUrl of subscriptions)
-    knownSubscriptions[subscriptionUrl] = modules.subscriptionClasses.Subscription.fromURL(subscriptionUrl);
-  var customSubscription = knownSubscriptions["~user~786254"];
+  let knownSubscriptions = Object.create(null);
+  for (let subscriptionUrl of subscriptions)
+  {
+    knownSubscriptions[subscriptionUrl] =
+      modules.subscriptionClasses.Subscription.fromURL(subscriptionUrl);
+  }
+  let customSubscription = knownSubscriptions["~user~786254"];
 
   if (params.addSubscription)
   {
     // We don't know how long it will take for the page to fully load
     // so we'll post the message after one second
-    setTimeout(function()
+    setTimeout(() =>
     {
       window.postMessage({
         type: "message",
@@ -444,7 +463,7 @@
     }, 1000);
   }
 
-  ext.devtools.onCreated.addListener(function(panel)
+  ext.devtools.onCreated.addListener(panel =>
   {
     // blocked request
     panel.sendMessage({
@@ -520,4 +539,4 @@
       }
     });
   });
-})(this);
+}