text: // META: title=EventSource: addEventListener()
        var test = async_test()
        test.step(function() {
          var source = new EventSource("resources/message.py")
          source.addEventListener("message", listener, false)
        })
        function listener(e) {
          test.step(function() {
            assert_equals("data", e.data)
            this.close()
          }, this)
          test.done()
        }
  
  
  