wp-includes/class-wp-tax-query.php:596Transforms a single query, from one field to another.
$queryarray$resulting_fieldstring public function transform_query( &$query, $resulting_field ) { if ( empty( $query['terms'] ) ) { return; } if ( $query['field'] === $resulting_field ) { return; } $resulting_field = sanitize_key( $resulting_field ); // Empty 'terms' always results in a null transformation. $terms = array_filter( $query['terms'] ); if ( empty( $terms ) ) { $query['terms'] = array(); $query['field'] = $resulting_field; return; } $args = array( 'get' => 'all', 'number' => 0, 'taxonomy' => $query['taxonomy'], 'update_term_meta_cache' => false, 'orderby' => 'none', ); // Term query parameter name depends on the 'field' being searched on. switch ( $query['field'] ) { case 'slug': $args['slug'] = $terms; break; case 'name': $args['name'] = $terms; break; case 'term_taxonomy_id': $args['term_taxonomy_id'] = $terms; break; default: $args['include'] = wp_parse_id_list( $terms ); break; } if ( ! is_taxonomy_hierarchical( $query['taxonomy'] ) ) { $args['number'] = count( $terms ); } $term_query = new WP_Term_Query(); $term_list = $term_query->query( $args ); if ( is_wp_error( $term_list ) ) { $query = $term_list; return; } if ( 'AND' === $query['operator'] && count( $term_list ) < count( $query['terms'] ) ) { $query = new WP_Error( 'inexistent_terms', __( 'Inexistent terms.' ) ); return; } $query['terms'] = wp_list_pluck( $term_list, $resulting_field ); $query['field'] = $resulting_field; }Introduced in 3.2.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/class-wp-tax-query.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.