third_party/WebKit/LayoutTests/fast/events/message-channel-gc-3.html

   1 <body>
   2 <p>Test that MessagePort messages are delivered even if both ports are inaccessible from JS any more.</p>
   3 <p>Should say PASS twice.</p>
   4 <pre id=log></pre>
   5 <script>
   6 function gc()
   7 {
   8     if (window.GCController)
   9         return GCController.collect();
  10
  11     for (var i = 0; i < 10000; i++) { // > force garbage collection (FF requires about 9K allocations before a collect)
  12         var s = new String("abc");
  13     }
  14 }
  15
  16 function log(message)
  17 {
  18     document.getElementById("log").innerHTML += message + "<br>";
  19 }
  20
  21 if (window.testRunner) {
  22     testRunner.dumpAsText();
  23     testRunner.waitUntilDone();
  24 }
  25
  26 function test1()
  27 {
  28     var channel = new MessageChannel;
  29
  30     channel.port1.onmessage = function(evt) { log("PASS: message delivered. Port: " + evt.target); test2(); }
  31     channel.port2.postMessage("msg");
  32
  33     channel = 0;
  34     gc();
  35 }
  36
  37 function test2()
  38 {
  39     var channel = new MessageChannel;
  40
  41     channel.port2.close();
  42
  43     channel = 0;
  44     gc();
  45     log("PASS: port closed.");
  46     if (window.testRunner)
  47         testRunner.notifyDone();
  48 }
  49
  50 test1();
  51
  52 </script>
  53 </body>