Issue 6599 - Detect data corruption of storage.local

lib/subscriptionInit.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 223 matching lines @@
   {
     FilterStorage.addSubscription(subscription);
     if (subscription instanceof DownloadableSubscription &&
         !subscription.lastDownload)
       Synchronizer.execute(subscription);
   }
 
   if (!Prefs.suppress_first_run_page)
   {
     let page = null;
-    if (firstRun)
+    if (firstRun || exports.dataCorrupted)

[kzar, 2018/04/24 11:18:01]

Well surely this would mean that the first run page constantly opens instead of
the updates page for these users with corrupted data?

Shouldn't we show a page which explains that their data is corrupted and that
they should try reinstalling the extension? Also I wonder if there's another way
to store a flag to somehow avoid constantly showing the page (or if that's a
good idea)?

[Sebastian Noack, 2018/04/24 11:26:26]

Yes, that is the idea, to add this message to the first run page, but hide it
unless dataCorrupted is set. Note that this how we already handle the
"reinitialized" flag.

[kzar, 2018/04/24 13:34:00]

Fair enough, I guess we need to also update the adblockplusui dependency to
include that with along with this change.

     {
       page = "firstRun.html";
     }
     // For now we're limiting the updates page to users of
     // Chromium-based browsers to gage its impact
     else if (info.platform == "chromium" &&
              updatesVersion > Prefs.last_updates_page_displayed)
     {
       page = "updates.html";
     }
 
     if (page)
     {
       browser.tabs.create({url: browser.extension.getURL(page)});
 
       // For new users and users that have already seen this updates page we
       // want to avoid showing it again for subsequent updates.
       Prefs.last_updates_page_displayed = updatesVersion;
     }
   }
 
   initNotifications();
 }
 
-Promise.all([FilterNotifier.once("load"),
-             Prefs.untilLoaded]).then(detectFirstRun)
-                                .then(getSubscriptions)
-                                .then(finishInitialization);
+Promise.all([
+  FilterNotifier.once("load"),
+  Prefs.untilLoaded.catch(() => { exports.dataCorrupted = true; })
+]).then(detectFirstRun)
+  .then(getSubscriptions)
+  .then(finishInitialization);
 
 /**
  * Indicates whether the default filter subscriptions have been added
  * again because there weren't any subscriptions even though this wasn't
  * the first run.
  *
  * @type {boolean}
  */
 exports.reinitialized = false;
 
 /**
+ * Indicates whether a data corruption was detcted.
+ *
+ * @type {boolean}
+ */
+exports.dataCorrupted = false;
+
+/**
  * Sets a callback that is called with an array of subscriptions to be added
  * during initialization. The callback must return an array of subscriptions
  * that will effectively be added.
  *
  * @param {function} callback
  */
 exports.setSubscriptionsCallback = callback =>
 {
   subscriptionsCallback = callback;
 };