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<html>
<!--
https://bugzilla.mozilla.org/show_bug.cgi?id=1604340
-->
<head>
  <meta charset="utf-8">
  <title>Test for Bug 1604340</title>
  <script src="/tests/SimpleTest/SimpleTest.js"></script>
  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
  <script type="application/javascript">
  /* global WrapperCachedNonISupportsTestInterface */
  SimpleTest.waitForExplicitFinish();
  SpecialPowers.pushPrefEnv({set: [["dom.expose_test_interfaces", true]]}, go);

  async function go() {
    await SpecialPowers.pushPrefEnv({set: [["dom.webidl.test1", false]]});
    let result = null;
    let constructorThrew = false;

    try {
      result = new WrapperCachedNonISupportsTestInterface();
    } catch {
      constructorThrew = true;
    }

    is(result, null, "The result value should remain null if the constructor threw an exception as intended.");
    ok(constructorThrew, "The constructor should throw an exception if its pref is not set to true.");

    await SpecialPowers.pushPrefEnv({set: [["dom.webidl.test1", true]]});
    result = null;
    constructorThrew = false;

    try {
      result = new WrapperCachedNonISupportsTestInterface();
    } catch {
      constructorThrew = true;
    }

    isnot(result, null, "Constructor should have executed successfully.");
    ok(!constructorThrew, "The constructor should not throw an exception if its pref is set.");

    SimpleTest.finish();
  }

  </script>
</head>
<body>
<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1604340">Mozilla Bug 1604340</a>
<p id="display"></p>
<div id="content" style="display: none">

</div>
<pre id="test">
</pre>
</body>
</html>
