public function test_transform_query_nonexistent_terms() { $tq = new WP_Tax_Query(array(array('terms' => array('foo'), 'field' => 'slug', 'operator' => 'AND'))); $tq->transform_query($tq->queries[0], 'term_taxonomy_id'); $this->assertTrue(is_wp_error($tq->queries[0])); }