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  <title>Event.returnValue</title>
  <link rel="author" title="Chris Rebert" href="http://chrisrebert.com">
  <link rel="help" href="https://dom.spec.whatwg.org/#dom-event-returnvalue">
  <meta name="flags" content="dom">
  <script src="/resources/testharness.js"></script>
  <script src="/resources/testharnessreport.js"></script>
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test(function() {
  var ev = new Event("foo");
  assert_true(ev.returnValue, "returnValue");
}, "When an event is created, returnValue should be initialized to true.");
test(function() {
  var ev = new Event("foo", {"cancelable": false});
  assert_false(ev.cancelable, "cancelable (before)");
  ev.preventDefault();
  assert_false(ev.cancelable, "cancelable (after)");
  assert_true(ev.returnValue, "returnValue");
}, "preventDefault() should not change returnValue if cancelable is false.");
test(function() {
  var ev = new Event("foo", {"cancelable": false});
  assert_false(ev.cancelable, "cancelable (before)");
  ev.returnValue = false;
  assert_false(ev.cancelable, "cancelable (after)");
  assert_true(ev.returnValue, "returnValue");
}, "returnValue=false should have no effect if cancelable is false.");
test(function() {
  var ev = new Event("foo", {"cancelable": true});
  assert_true(ev.cancelable, "cancelable (before)");
  ev.preventDefault();
  assert_true(ev.cancelable, "cancelable (after)");
  assert_false(ev.returnValue, "returnValue");
}, "preventDefault() should change returnValue if cancelable is true.");
test(function() {
  var ev = new Event("foo", {"cancelable": true});
  assert_true(ev.cancelable, "cancelable (before)");
  ev.returnValue = false;
  assert_true(ev.cancelable, "cancelable (after)");
  assert_false(ev.returnValue, "returnValue");
}, "returnValue should change returnValue if cancelable is true.");
test(function() {
  var ev = document.createEvent("Event");
  ev.returnValue = false;
  ev.initEvent("foo", true, true);
  assert_true(ev.bubbles, "bubbles");
  assert_true(ev.cancelable, "cancelable");
  assert_true(ev.returnValue, "returnValue");
}, "initEvent should unset returnValue.");
test(function() {
  var ev = new Event("foo");
  ev.preventDefault();
  ev.returnValue = true;// no-op
  assert_true(ev.defaultPrevented);
  assert_false(ev.returnValue);
}, "returnValue=true should have no effect once the canceled flag was set.");
  </script>
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