Issue 4878 - Start using ESLint for adblockpluscore

lib/events.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 16 matching lines @@
   this._listeners = Object.create(null);
 };
 
 exports.EventEmitter.prototype = {
   /**
    * Adds a listener for the specified event name.
    *
    * @param {string}   name
    * @param {function} listener
    */
-  on: function(name, listener)
+  on(name, listener)
   {
     if (name in this._listeners)
       this._listeners[name].push(listener);
     else
       this._listeners[name] = [listener];
   },
 
   /**
    * Removes a listener for the specified event name.
    *
    * @param {string}   name
    * @param {function} listener
    */
-  off: function(name, listener)
+  off(name, listener)
   {
     let listeners = this._listeners[name];
     if (listeners)
     {
       let idx = listeners.indexOf(listener);
       if (idx != -1)
         listeners.splice(idx, 1);
     }
   },
 
   /**
    * Adds a one time listener and returns a promise that
    * is resolved the next time the specified event is emitted.
-   *
+   * @param {String} name
    * @return {Promise}
    */
-  once: function(name)
+  once(name)
   {
     return new Promise(resolve =>
     {
       let listener = () =>
       {
         this.off(name, listener);
         resolve();
       };
 
       this.on(name, listener);
     });
   },
 
   /**
    * Returns a copy of the array of listeners for the specified event.
    *
    * @param {string} name
    * @return {function[]}
    */
-  listeners: function(name)
+  listeners(name)
   {
     let listeners = this._listeners[name];
     return listeners ? listeners.slice() : [];
   },
 
   /**
    * Calls all previously added listeners for the given event name.
    *
    * @param {string} name
    * @param {...*}   [arg]
    */
-  emit: function(name)
+  emit(name, ...args)
   {
-    let args = [];
-    for (let i = 1; i < arguments.length; i++)
-      args.push(arguments[i]);
-
     let listeners = this.listeners(name);
     for (let listener of listeners)
-      listener.apply(null, args);
+      listener(...args);
   }
 };