def METHOD_NAME(self):
    """Test that it can be called with only data set to None."""
    st._legacy_vega_lite_chart(None, {"mark": "rect"})
    c = self.get_delta_from_queue().new_element.vega_lite_chart
    self.assertEqual(c.HasField("data"), False)
    self.assertDictEqual(
        json.loads(c.spec), merge_dicts(autosize_spec, {"mark": "rect"})
    )