def METHOD_NAME():
    df = pd.DataFrame([])
    widget = AutoVizWidget(
        df,
        encoding,
        renderer,
        ipywidget_factory,
        encoding_widget,
        ipython_display,
        spark_events=spark_events,
        testing=True,
    )
    ipywidget_factory.get_button.assert_not_called()
    ipywidget_factory.get_html.assert_called_once_with("No results.")
    ipython_display.display.assert_called_with(ipywidget_factory.get_html.return_value)
    spark_events.emit_graph_render_event.assert_called_once_with(encoding.chart_type)