def METHOD_NAME(self):
    """Test that form id is marshalled correctly inside of a form."""
    with st.form("form"):
        st.text_area("foo")
    # 2 elements will be created: form block, widget
    self.assertEqual(len(self.get_all_deltas_from_queue()), 2)
    form_proto = self.get_delta_from_queue(0).add_block
    text_area_proto = self.get_delta_from_queue(1).new_element.text_area
    self.assertEqual(text_area_proto.form_id, form_proto.form.form_id)