def test_fill_form_missing_values(browser, app_url):
    """Missing values should raise an error."""
    browser.visit(app_url)
    with pytest.raises(ElementDoesNotExist) as e:
        browser.fill_form(
            {"query": "new query", "missing_form": "doesn't exist"},
        )

    assert "missing_form" in str(e.value)
Missing values should raise an error.
tests/test_all_drivers/test_form_elements.py