  assert_equals(source, location.href, 'second arg');
        assert_equals(typeof lineno, 'number', 'third arg');
    });
    t_col.step(function(){
        assert_equals(typeof colno, 'number', 'fourth arg');
    });
    ">
  <div id=log></div>
  <script>
    undefined_variable;
  </script>
  <script>
    t.step(function(){
        assert_true(ran, 'ran');
        t.done();
    });
    t_col.step(function(){
        t_col.done();
    });
  </script>
 </body>
</html>
