def test_no_xsd_warning(self):
        """Test whether the metadata can still be retrieved, and that the
        XSD values are unavailable. Also test if a warning is given to the
        user."""
        with pytest.warns(XsdFetchWarning):
            gwf = GrondwaterFilterSearch(
                objecttype=pydov.types.grondwaterfilter.GrondwaterFilter)
            fields = gwf.get_fields()

        assert 'values' not in fields['aquifer_code']