assertEquals("", getAsQuery(Collections.singletonMap(k, new String[] { "invalid" })));
    }

    @Test
    public void test_escape_method() {
        // Test escape functionality through quote escaping in epq conditions
        final String k = "epq";
        assertEquals("\"a\\\"aa\"", getAsQuery(Collections.singletonMap(k, new String[] { "a\"aa" })));