content/base/test/chrome/test_bug429785.xul

<?xml version="1.0"?>
<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css" type="text/css"?>
<!--
https://bugzilla.mozilla.org/show_bug.cgi?id=429785
-->
<window title="Mozilla Bug 429785"
  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
  <script type="application/javascript" src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>

  <!-- test results are displayed in the html:body -->
  <body xmlns="http://www.w3.org/1999/xhtml">
  <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=429785"
     target="_blank">Mozilla Bug 429785</a>
  </body>

  <!-- test code goes here -->
  <script type="application/javascript"><![CDATA[
    /** Test for Bug 429785 **/
    SimpleTest.waitForExplicitFinish();
    var errorLogged = false;
    const serv = Components.classes["@mozilla.org/consoleservice;1"]
                           .getService(Components.interfaces.nsIConsoleService);
    var listener = {
      QueryInteface : function(iid) {
        if (!iid.equals(Components.interfaces.nsISupports) &&
            !iid.equals(Components.interfaces.nsIConsoleListener)) {
	  throw Components.results.NS_NOINTERFACE;
	}
	return this;
      },
      observe : function (msg) { errorLogged = true; }
    };

    function step2() {
      is(errorLogged, false, "Should be no errors");

      serv.registerListener(listener);    
      try {
        serv.logStringMessage("This is a test");
      } finally {
        serv.unregisterListener(listener);
      }

      setTimeout(step3, 0);

    }

    function step3() {
      is(errorLogged, true, "Should see errors when they happen");
      SimpleTest.finish();
    }
        
    serv.registerListener(listener);    
    try {
      var p = new DOMParser();
      p.parseFromString("<root/>", "application/xml");

      // nsConsoleService notifies its listeners via async proxies, so we need
      // to wait to see whether there was an error reported.
      setTimeout(step2, 0);
    } finally {
      serv.unregisterListener(listener);
    }

  ]]></script>
</window>