Issue 6482 - Use ES6 classes

ext/background.js

Index: ext/background.js
===================================================================
--- a/ext/background.js
+++ b/ext/background.js
@@ -15,73 +15,83 @@
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 "use strict";
 
 {
   let nonEmptyPageMaps = new Set();
 
-  let PageMap = ext.PageMap = function()
+  ext.PageMap = class
   {
-    this._map = new Map();
-  };
-  PageMap.prototype = {
+    constructor()
+    {
+      this._map = new Map();
+    }
+
     _delete(id)
     {
       this._map.delete(id);
 
       if (this._map.size == 0)
         nonEmptyPageMaps.delete(this);
-    },
+    }
+

[Manish Jethani, 2018/03/15 07:54:10]

I think it's better with a blank line between the methods but let me know if you
disagree.

     keys()
     {
       return Array.from(this._map.keys()).map(ext.getPage);
-    },
+    }
+
     get(page)
     {
       return this._map.get(page.id);
-    },
+    }
+
     set(page, value)
     {
       this._map.set(page.id, value);
       nonEmptyPageMaps.add(this);
-    },
+    }
+
     has(page)
     {
       return this._map.has(page.id);
-    },
+    }
+
     clear()
     {
       this._map.clear();
       nonEmptyPageMaps.delete(this);
-    },
+    }
+
     delete(page)
     {
       this._delete(page.id);
     }
   };

[Manish Jethani, 2018/03/15 07:54:10]

Note that this is a class expression so it ends in a semicolon (similar to
function expression).

 
   ext._removeFromAllPageMaps = pageId =>
   {
     for (let pageMap of nonEmptyPageMaps)
       pageMap._delete(pageId);
   };
 
   /* Pages */
 
-  let Page = ext.Page = function(tab)
+  ext.Page = class
   {
-    this.id = tab.id;
-    this._url = tab.url && new URL(tab.url);
+    constructor(tab)
+    {
+      this.id = tab.id;
+      this._url = tab.url && new URL(tab.url);
 
-    this.browserAction = new BrowserAction(tab.id);
-    this.contextMenus = new ContextMenus(this);
-  };
-  Page.prototype = {
+      this.browserAction = new BrowserAction(tab.id);
+      this.contextMenus = new ContextMenus(this);
+    }
+
     get url()
     {
       // usually our Page objects are created from Chrome's Tab objects, which
       // provide the url. So we can return the url given in the constructor.
       if (this._url)
         return this._url;
 
       // but sometimes we only have the tab id when we create a Page object.
@@ -89,51 +99,52 @@
       // the onBeforeRequest handler.
       let frames = framesOfTabs.get(this.id);
       if (frames)
       {
         let frame = frames.get(0);
         if (frame)
           return frame.url;
       }
-    },
+    }
+
     sendMessage(message, responseCallback)
     {
       browser.tabs.sendMessage(this.id, message, responseCallback);
     }
   };
 
-  ext.getPage = id => new Page({id: parseInt(id, 10)});
+  ext.getPage = id => new ext.Page({id: parseInt(id, 10)});

[Manish Jethani, 2018/03/15 07:54:10]

There was no real need for the local PageMap variable so I removed it, instead
we use ext.PageMap directly.

 
   function afterTabLoaded(callback)
   {
     return openedTab =>
     {
       let onUpdated = (tabId, changeInfo, tab) =>
       {
         if (tabId == openedTab.id && changeInfo.status == "complete")
         {
           browser.tabs.onUpdated.removeListener(onUpdated);
-          callback(new Page(openedTab));
+          callback(new ext.Page(openedTab));
         }
       };
       browser.tabs.onUpdated.addListener(onUpdated);
     };
   }
 
   ext.pages = {
     onLoading: new ext._EventTarget(),
     onActivated: new ext._EventTarget(),
     onRemoved: new ext._EventTarget()
   };
 
   browser.tabs.onUpdated.addListener((tabId, changeInfo, tab) =>
   {
     if (changeInfo.status == "loading")
-      ext.pages.onLoading._dispatch(new Page(tab));
+      ext.pages.onLoading._dispatch(new ext.Page(tab));
   });
 
   function createFrame(tabId, frameId)
   {
     let frames = framesOfTabs.get(tabId);
     if (!frames)
     {
       frames = new Map();
@@ -149,17 +160,17 @@
 
     return frame;
   }
 
   function updatePageFrameStructure(frameId, tabId, url, parentFrameId)
   {
     if (frameId == 0)
     {
-      let page = new Page({id: tabId, url});
+      let page = new ext.Page({id: tabId, url});
 
       ext._removeFromAllPageMaps(tabId);
 
       browser.tabs.get(tabId, () =>
       {
         // If the tab is prerendered, browser.tabs.get() sets
         // browser.runtime.lastError and we have to dispatch the onLoading
         // event, since the onUpdated event isn't dispatched for prerendered
@@ -287,28 +298,30 @@
   {
     forgetTab(removedTabId);
   });
 
   browser.tabs.onRemoved.addListener(forgetTab);
 
   browser.tabs.onActivated.addListener(details =>
   {
-    ext.pages.onActivated._dispatch(new Page({id: details.tabId}));
+    ext.pages.onActivated._dispatch(new ext.Page({id: details.tabId}));
   });
 
 
   /* Browser actions */
 
-  let BrowserAction = function(tabId)
+  class BrowserAction
   {
-    this._tabId = tabId;
-    this._changes = null;
-  };
-  BrowserAction.prototype = {
+    constructor(tabId)
+    {
+      this._tabId = tabId;
+      this._changes = null;
+    }
+
     _applyChanges()
     {
       if ("iconPath" in this._changes)
       {
         // Firefox for Android displays the browser action not as an icon but
         // as a menu item. There is no icon, but such an option may be added in
         // the future.
         // https://bugzilla.mozilla.org/show_bug.cgi?id=1331746
@@ -358,17 +371,18 @@
           browser.browserAction.setBadgeBackgroundColor({
             tabId: this._tabId,
             color: this._changes.badgeColor
           });
         }
       }
 
       this._changes = null;
-    },
+    }
+
     _queueChanges()
     {
       browser.tabs.get(this._tabId, () =>
       {
         // If the tab is prerendered, browser.tabs.get() sets
         // browser.runtime.lastError and we have to delay our changes
         // until the currently visible tab is replaced with the
         // prerendered tab. Otherwise browser.browserAction.set* fails.
@@ -384,47 +398,50 @@
           };
           browser.tabs.onReplaced.addListener(onReplaced);
         }
         else
         {
           this._applyChanges();
         }
       });
-    },
+    }
+
     _addChange(name, value)
     {
       if (!this._changes)
       {
         this._changes = {};
         this._queueChanges();
       }
 
       this._changes[name] = value;
-    },
+    }
+
     setIcon(path)
     {
       this._addChange("iconPath", path);
-    },
+    }
+
     setBadge(badge)
     {
       if (!badge)
       {
         this._addChange("badgeText", "");
       }
       else
       {
         if ("number" in badge)
           this._addChange("badgeText", badge.number.toString());
 
         if ("color" in badge)
           this._addChange("badgeColor", badge.color);
       }
     }
-  };
+  }
 
 
   /* Context menus */
 
   let contextMenuItems = new ext.PageMap();
   let contextMenuUpdating = false;
 
   let updateContextMenu = () =>
@@ -452,52 +469,55 @@
 
         items.forEach(item =>
         {
           browser.contextMenus.create({
             title: item.title,
             contexts: item.contexts,
             onclick(info, tab)
             {
-              item.onclick(new Page(tab));
+              item.onclick(new ext.Page(tab));
             }
           });
         });
       });
     });
   };
 
-  let ContextMenus = function(page)
+  class ContextMenus
   {
-    this._page = page;
-  };
-  ContextMenus.prototype = {
+    constructor(page)
+    {
+      this._page = page;
+    }
+
     create(item)
     {
       let items = contextMenuItems.get(this._page);
       if (!items)
         contextMenuItems.set(this._page, items = []);
 
       items.push(item);
       updateContextMenu();
-    },
+    }
+
     remove(item)
     {
       let items = contextMenuItems.get(this._page);
       if (items)
       {
         let index = items.indexOf(item);
         if (index != -1)
         {
           items.splice(index, 1);
           updateContextMenu();
         }
       }
     }
-  };
+  }
 
   browser.tabs.onActivated.addListener(updateContextMenu);
 
   if ("windows" in browser)
   {
     browser.windows.onFocusChanged.addListener(windowId =>
     {
       if (windowId != browser.windows.WINDOW_ID_NONE)
@@ -614,17 +634,17 @@
 
     // Sometimes requests are not associated with a browser tab and
     // in this case we want to still be able to view the url being called.
     let frame = null;
     let page = null;
     if (details.tabId != -1)
     {
       frame = ext.getFrame(details.tabId, frameId);
-      page = new Page({id: details.tabId});
+      page = new ext.Page({id: details.tabId});
     }
 
     if (ext.webRequest.onBeforeRequest._dispatch(
         url, type, page, frame).includes(false))
       return {cancel: true};
   }, {urls: ["<all_urls>"]}, ["blocking"]);
 
 
@@ -633,17 +653,17 @@
   browser.runtime.onMessage.addListener((message, rawSender, sendResponse) =>
   {
     let sender = {};
 
     // Add "page" and "frame" if the message was sent by a content script.
     // If sent by popup or the background page itself, there is no "tab".
     if ("tab" in rawSender)
     {
-      sender.page = new Page(rawSender.tab);
+      sender.page = new ext.Page(rawSender.tab);
       sender.frame = {
         id: rawSender.frameId,
         // In Edge requests from internal extension pages
         // (protocol ms-browser-extension://) do no have a sender URL.
         url: rawSender.url ? new URL(rawSender.url) : null,
         get parent()
         {
           let frames = framesOfTabs.get(rawSender.tab.id);