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 /* This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this

  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

 /* See https://bugzilla.mozilla.org/show_bug.cgi?id=317304 */

 function run_test()

 {

   // Bug 712649: Calling getWeakReference(null) should work.

   try {

     var nullWeak = Components.utils.getWeakReference(null);

     do_check_true(nullWeak.get() === null);

   } catch (e) {

     do_check_true(false);

   }

   var obj = { num: 5, str: 'foo' };

   var weak = Components.utils.getWeakReference(obj);

   do_check_true(weak.get() === obj);

   do_check_true(weak.get().num == 5);

   do_check_true(weak.get().str == 'foo');

   // Force garbage collection

   Components.utils.forceGC();

   // obj still references the object, so it should still be accessible via weak

   do_check_true(weak.get() === obj);

   do_check_true(weak.get().num == 5);

   do_check_true(weak.get().str == 'foo');

   // Clear obj's reference to the object and force garbage collection. To make

   // sure that there are no instances of obj stored in the registers or on the

   // native stack and the conservative GC would not find it we force the same

   // code paths that we used for the initial allocation.

   obj = { num: 6, str: 'foo2' };

   var weak2 = Components.utils.getWeakReference(obj);

   do_check_true(weak2.get() === obj);

   Components.utils.forceGC();

   // The object should have been garbage collected and so should no longer be

   // accessible via weak

   do_check_true(weak.get() === null);

 }