The Tor Browser / file revision

 /* Any copyright is dedicated to the Public Domain.

    http://creativecommons.org/publicdomain/zero/1.0/ */

 /**

  * Verifies that hidden, pre-loaded newtabs don't allow background captures, and

  * when unhidden, do allow background captures.

  */

 const CAPTURE_PREF = "browser.pagethumbnails.capturing_disabled";

 function runTests() {

   let imports = {};

   Cu.import("resource://gre/modules/PageThumbs.jsm", imports);

   Cu.import("resource:///modules/BrowserNewTabPreloader.jsm", imports);

   // Disable captures.

   let originalDisabledState = Services.prefs.getBoolPref(CAPTURE_PREF);

   Services.prefs.setBoolPref(CAPTURE_PREF, true);

   // Make sure the thumbnail doesn't exist yet.

   let siteName = "newtab_background_captures";

   let url = "http://example.com/#" + siteName;

   let path = imports.PageThumbsStorage.getFilePathForURL(url);

   let file = Cc["@mozilla.org/file/local;1"].createInstance(Ci.nsIFile);

   file.initWithPath(path);

   try {

     file.remove(false);

   }

   catch (err) {}

   // Add a top site.

   yield setLinks(siteName);

   // We need a handle to a hidden, pre-loaded newtab so we can verify that it

   // doesn't allow background captures.  Add a newtab, which triggers creation

   // of a hidden newtab, and then keep calling BrowserNewTabPreloader.newTab

   // until it returns true, meaning that it swapped the passed-in tab's docshell

   // for the hidden newtab docshell.

   let tab = gWindow.gBrowser.addTab("about:blank");

   yield addNewTabPageTab();

   let swapWaitCount = 0;

   let swapped = imports.BrowserNewTabPreloader.newTab(tab);

   while (!swapped) {

     if (++swapWaitCount == 10) {

       ok(false, "Timed out waiting for newtab docshell swap.");

       return;

     }

     // Give the hidden newtab some time to finish loading.

     yield wait(2000);

     info("Checking newtab swap " + swapWaitCount);

     swapped = imports.BrowserNewTabPreloader.newTab(tab);

   }

   // The tab's docshell is now the previously hidden newtab docshell.

   let doc = tab.linkedBrowser.contentDocument;

   isnot(doc.documentElement.getAttribute("allow-background-captures"), "true",

         "Pre-loaded docshell just synchronously swapped, so background " +

         "captures should not be allowed yet");

   // Enable captures.

   Services.prefs.setBoolPref(CAPTURE_PREF, false);

   // Now that the newtab is visible, its allow-background-captures attribute

   // should be set eventually.

   let allowBackgroundCaptures = false;

   let mutationObserver = new MutationObserver(() => {

     mutationObserver.disconnect();

     allowBackgroundCaptures = true;

     is(doc.documentElement.getAttribute("allow-background-captures"), "true",

        "allow-background-captures should now be true");

     info("Waiting for thumbnail to be created after observing " +

          "allow-background-captures change");

   });

   mutationObserver.observe(doc.documentElement, {

     attributes: true,

     attributeFilter: ["allow-background-captures"],

   });

   // And the allow-background-captures change should trigger the thumbnail

   // capture.

   Services.obs.addObserver(function onCreate(subj, topic, data) {

     if (data != url)

       return;

     ok(allowBackgroundCaptures,

        "page-thumbnail:create should be observed after " +

        "allow-background-captures was set");

     Services.obs.removeObserver(onCreate, "page-thumbnail:create");

     // Test finished!

     Services.prefs.setBoolPref(CAPTURE_PREF, originalDisabledState);

     file.remove(false);

     TestRunner.next();

   }, "page-thumbnail:create", false);

   info("Waiting for allow-background-captures change");

   yield true;

 }

 function wait(ms) {

   setTimeout(TestRunner.next, ms);

 }