Issue 5582 - Workaround Edge bug in tabs.query

ext/background.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-present 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 681 matching lines @@
     {
       chrome.storage.local.remove(key, callback);
     },
     onChanged: chrome.storage.onChanged
   };
 
   /* Options */
 
   ext.showOptions = callback =>
   {
+    let info = require("info");
+
     if ("openOptionsPage" in chrome.runtime &&
-        // Firefox for Android does have a runtime.openOptionsPage but it
-        // doesn't do anything.
+        // Some versions of Firefox for Android before version 57 do have a
+        // runtime.openOptionsPage but it doesn't do anything.
         // https://bugzilla.mozilla.org/show_bug.cgi?id=1364945
-        require("info").application != "fennec")
+        (info.application != "fennec" ||
+         parseInt(info.applicationVersion, 10) >= 57))
     {
       if (!callback)
       {
         chrome.runtime.openOptionsPage();
       }
       else
       {
         chrome.runtime.openOptionsPage(() =>
         {
           if (chrome.runtime.lastError)
             return;
 
           chrome.tabs.query({active: true, lastFocusedWindow: true}, tabs =>
           {
             if (tabs.length > 0)
             {
               if (tabs[0].status == "complete")
                 callback(new Page(tabs[0]));
               else
                 afterTabLoaded(callback)(tabs[0]);
             }
           });
         });
       }
     }
-    else
+    else if ("windows" in chrome)
     {
       // Edge does not yet support runtime.openOptionsPage (tested version 38)
-      // nor does Firefox for Android,
       // and so this workaround needs to stay for now.
       // We are not using extension.getURL to get the absolute path here
       // because of the Edge issue:
       // https://developer.microsoft.com/en-us/microsoft-edge/platform/issues/10276332/
       let optionsUrl = "options.html";
-      let fullOptionsUrl = ext.getURL("options.html");
+      let fullOptionsUrl = ext.getURL(optionsUrl);
 
       chrome.tabs.query({}, tabs =>
       {
         // We find a tab ourselves because Edge has a bug when quering tabs
         // with extension URL protocol:
         // https://developer.microsoft.com/en-us/microsoft-edge/platform/issues/8094141/ 
         // https://developer.microsoft.com/en-us/microsoft-edge/platform/issues/8604703/
-        let tab = tabs == null ? null : tabs.find(element => 

[Sebastian Noack, 2017/08/29 04:04:26]

In which case is `tabs == null`? According to my understanding of this API that
should never happen.

If this check is indeed necessary `tabs && ...` would be more concise than the
tertiary operator.

[Manish Jethani, 2017/08/29 04:18:33]

tabs was null on Firefox for Android when we were querying for options.html but
we're not doing that anymore so it should not be null for that reason. 

Firefox for Android avoids this code path entirely now (changeset 4f89fd4b176a),
if we simply rebase this patch it should be a lot clearer.

-        {
-          return element.url == fullOptionsUrl;

[Sebastian Noack, 2017/08/29 04:04:26]

The braces + return statement is redundant for single assignment arrow
functions.

-        });
-
+        let tab = tabs.find(element => element.url == fullOptionsUrl);
         if (tab)
         {
-          // Firefox for Android does not support the windows API. Since there
-          // is effectively only one window on the mobile browser, there's no
-          // need to bring it into focus.
-          if ("windows" in chrome)
-            chrome.windows.update(tab.windowId, {focused: true});
-
+          chrome.windows.update(tab.windowId, {focused: true});
           chrome.tabs.update(tab.id, {active: true});
 
           if (callback)
             callback(new Page(tab));
         }
         else
         {
           ext.pages.open(optionsUrl, callback);
         }
       });
+    }
+    else
+    {
+      // Firefox for Android before version 57 does not support
+      // runtime.openOptionsPage, nor does it support the windows API. Since
+      // there is effectively only one window on the mobile browser, there's no
+      // need to bring it into focus.
+      ext.pages.open("options.html", callback);
     }
   };
 
   /* Windows */
   ext.windows = {
     create(createData, callback)
     {
       chrome.windows.create(createData, createdWindow =>
       {
         afterTabLoaded(callback)(createdWindow.tabs[0]);
       });
     }
   };
 }());