@Test
    void testInvalidSortFunction() {
        assertQueryError(
                "?query=test&sortspec=-ucca(name,en_US)",
                "Could not set 'ranking.sorting' to '-ucca(name,en_US)': Unknown sort function 'ucca' at [-ucca(][name,en_US)]");
    }
Test that the integer convenience wrapper works as documented,
throwing NumberFormatException when applied to something that
is not a number.
container-search/src/test/java/com/yahoo/prelude/test/QueryTestCase.java