public function update( &$order ) {
    $order->save_meta_data();
    $order->set_version( Constants::get_constant( 'WC_VERSION' ) );

    if ( null === $order->get_date_created( 'edit' ) ) {
      $order->set_date_created( time() );
    }

    $changes = $order->get_changes();

    // Only update the post when the post data changes.
    if ( array_intersect( array( 'date_created', 'date_modified', 'status', 'parent_id', 'post_excerpt' ), array_keys( $changes ) ) ) {
      $post_data = array(
        'post_date'         => gmdate( 'Y-m-d H:i:s', $order->get_date_created( 'edit' )->getOffsetTimestamp() ),
        'post_date_gmt'     => gmdate( 'Y-m-d H:i:s', $order->get_date_created( 'edit' )->getTimestamp() ),
        'post_status'       => $this->get_post_status( $order ),
        'post_parent'       => $order->get_parent_id(),
        'post_excerpt'      => $this->get_post_excerpt( $order ),
        'post_modified'     => isset( $changes['date_modified'] ) ? gmdate( 'Y-m-d H:i:s', $order->get_date_modified( 'edit' )->getOffsetTimestamp() ) : current_time( 'mysql' ),
        'post_modified_gmt' => isset( $changes['date_modified'] ) ? gmdate( 'Y-m-d H:i:s', $order->get_date_modified( 'edit' )->getTimestamp() ) : current_time( 'mysql', 1 ),
      );

      
/**
 * When updating this object, to prevent infinite loops, use $wpdb
 * to update data, since wp_update_post spawns more calls to the
 * save_post action.
 *
 * This ensures hooks are fired by either WP itself (admin screen save),
 * or an update purely from CRUD.
 */
      if ( doing_action( 'save_post' ) ) {
        $GLOBALS['wpdb']->update( $GLOBALS['wpdb']->posts, $post_data, array( 'ID' => $order->get_id() ) );
        clean_post_cache( $order->get_id() );
      } else {
        wp_update_post( array_merge( array( 'ID' => $order->get_id() ), $post_data ) );
      }
      $order->read_meta_data( true ); // Refresh internal meta data, in case things were hooked into `save_post` or another WP hook.
    }
    $this->update_post_meta( $order );
    $order->apply_changes();
    $this->clear_caches( $order );
  }