third_party/WebKit/LayoutTests/storage/indexeddb/cursor-leak.html

   1 <!DOCTYPE html>
   2 <script src="../../resources/js-test.js"></script>
   3 <script src="resources/shared.js"></script>
   4 <script>
   5
   6 description("Verify that that cursors weakly hold script value properties");
   7
   8 if (window.internals) {
   9     indexedDBTest(prepareDatabase, onOpen);
  10 } else {
  11     testFailed('This test requires access to the Internals object');
  12     finishJSTest();
  13 }
  14
  15 function prepareDatabase(evt)
  16 {
  17     db = event.target.result;
  18     store = db.createObjectStore('store');
  19     store.put({value: 'value'}, ['key']);
  20 }
  21
  22 function onOpen(evt)
  23 {
  24     // evalAndLog() is not used as that generates new DOM nodes.
  25
  26     db = evt.target.result;
  27     tx = db.transaction('store');
  28     store = tx.objectStore('store');
  29     cursorRequest = store.openCursor();
  30     cursorRequest.onsuccess = function() {
  31         cursor = cursorRequest.result;
  32     };
  33     tx.oncomplete = function() {
  34         db.close();
  35
  36         // Try and induce a leak by a reference cycle from DOM to V8 and back.
  37         // If the v8 value of cursor.key (etc) is only held by the cursor's
  38         // V8 wrapper then there will be no leak.
  39         cursor.key.cursor = cursor;
  40         cursor.primaryKey.cursor = cursor;
  41         cursor.value.cursor = cursor;
  42
  43         cursorObserver = internals.observeGC(cursor);
  44
  45         cursorRequest = null;
  46         cursor = null;
  47
  48         gc();
  49
  50         shouldBeTrue("cursorObserver.wasCollected");
  51         finishJSTest();
  52     };
  53 }
  54
  55
  56 </script>