Issue 4871 - Start using ESLint for adblockplusui

background.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
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 "use strict";
 
+(function()
 {
   function EventEmitter()
   {
     this._listeners = Object.create(null);
   }
   EventEmitter.prototype = {
     on(name, listener)
     {
       if (name in this._listeners)
         this._listeners[name].push(listener);
@@ skipping 18 matching lines @@
         for (let listener of listeners)
           listener(...args);
       }
     }
   };
 
   function updateFromURL(data)
   {
     if (window.location.search)
     {
-      for (let param of window.location.search.substr(1).split("&"))

[Thomas Greiner, 2017/03/01 17:39:32]

Detail: Putting that long statement within the for-of loop makes it more
difficult to read so I'd prefer keeping the interstitial `params` variable.

[kzar, 2017/03/07 12:48:31]

Done.

+      let params = window.location.search.substr(1).split("&");
+
+      for (let param of params)
       {
         let parts = param.split("=", 2);
         if (parts.length == 2 && parts[0] in data)
           data[parts[0]] = decodeURIComponent(parts[1]);
       }
     }
   }
 
   let params = {
     blockedURLs: "",
@@ skipping 129 matching lines @@
         return subscriptions;
       },
 
       get knownSubscriptions()
       {
         return knownSubscriptions;
       },
 
       addSubscription(subscription)
       {
-        let {fromURL} = modules.subscriptionClasses.Subscription;

[Thomas Greiner, 2017/03/01 17:39:34]

Detail: You can now refer to `Subscription` directly so
`modules.subscriptionClasses.` is redundant.

[kzar, 2017/03/07 12:48:31]

Done.

+        let {fromURL} = Subscription;
         let {FilterStorage} = modules.filterStorage;
 
         if (!(subscription.url in FilterStorage.knownSubscriptions))
         {
           knownSubscriptions[subscription.url] = fromURL(subscription.url);
           modules.filterNotifier.FilterNotifier.emit("subscription.added",
                                                      subscription);
         }
       },
 
@@ skipping 34 matching lines @@
         }
       }
     }
   };
 
   function Filter(text)
   {
     this.text = text;
     this.disabled = false;
   }
-  Filter.fromText = text =>

[Thomas Greiner, 2017/03/01 17:39:34]

Detail: Mind writing this as follows?

Filter.fromText = (text) => new Filter(text);

1) Suggestion: For consistency, always having brackets around arrow function
parameters makes changing code a bit easier.

2) The `return` is redundant in arrow functions.

3) You can refer to `Filter` directly now so `modules.filterClasses.` is
redundant.

[kzar, 2017/03/07 12:48:30]

Done.

-  {
-    return new modules.filterClasses.Filter(text);
-  };
+  Filter.fromText = (text) => new Filter(text);
 
   function BlockingFilter()
   {
   }
 
   function RegExpFilter()
   {
   }
   RegExpFilter.typeMap = Object.create(null);
 
@@ skipping 10 matching lines @@
       if (params.filterError)
         return {error: "Invalid filter"};
       return {filter: modules.filterClasses.Filter.fromText(text)};
     },
     parseFilters(text)
     {
       if (params.filterError)
         return {errors: ["Invalid filter"]};
       return {
         filters: text.split("\n")
-          .filter(filter => !!filter)
+          .filter((filter) => !!filter)
           .map(modules.filterClasses.Filter.fromText),
         errors: []
       };
     }
   };
 
   modules.synchronizer = {
     Synchronizer: {
       _downloading: false,
       execute(subscription, manual)
@@ skipping 46 matching lines @@
   updateFromURL(modules.info);
 
   modules.subscriptionInit = {
     reinitialized: params.filterlistsReinitialized
   };
 
   modules.messaging = {
     port: new EventEmitter()
   };
 
-  window.addEventListener("message", event =>
+  window.addEventListener("message", (event) =>
   {
     if (event.data.type != "message")
       return;
     let message = event.data.payload;
     let {messageId} = event.data;
     let sender = {
       page: new ext.Page(event.source)
     };
 
     let listeners = modules.messaging.port._listeners[message.type];
     if (!listeners)
       return;
 
     function reply(responseMessage)
     {
       event.source.postMessage({
         type: "response",
         messageId,
         payload: responseMessage
       }, "*");
     }
 
     for (let listener of listeners)
     {
       let response = listener(message, sender);
       if (response && typeof response.then == "function")
       {
         response.then(
           reply,
-          reason =>
+          (reason) =>
           {
             console.error(reason);
             reply(undefined);
           }
         );
       }
       else if (typeof response != "undefined")
+      {
         reply(response);
+      }
     }
   });
 
   window.Services = {
     vc: {
       compare(v1, v2)
       {
         return parseFloat(v1) - parseFloat(v2);
       }
     }
@@ skipping 48 matching lines @@
         payload: {
           title: "Custom subscription",
           url: "http://example.com/custom.txt",
           confirm: true,
           type: "subscriptions.add"
         }
       }, "*");
     }, 1000);
   }
 
-  ext.devtools.onCreated.addListener(panel =>
+  ext.devtools.onCreated.addListener((panel) =>
   {
     // blocked request
     panel.sendMessage({
       type: "add-record",
       request: {
         url: "http://adserver.example.com/ad_banner.png",
         type: "IMAGE",
         docDomain: "example.com"
       },
       filter: {
@@ skipping 55 matching lines @@
         docDomain: "example.com"
       },
       filter: {
         text: "||example.com/some-annoying-popup$popup",
         whitelisted: false,
         userDefined: true,
         subscription: null
       }
     });
   });
-}
+}());