The work of Wordpress Function update_post

Question

I use wp_update_post() in a Frontend Page. The first part of the function works as expected. post_content and/or post_title will be changed in wp_posts. But the function does not create a revision copy from the old table item as described in the WP Function Reference.

Here is my code

$upd_post = array();
$upd_post['ID'] = $post->ID;
$upd_post['post_title'] = $wp_query->query_vars['4tn_title'];
$upd_post['post_content'] = $wp_query->query_vars['4tn_content'];
$update_result = wp_update_post( $upd_post );

Perhaps it doesn't work because the post_type is a cutom-type 'portfolio' instead 'post'.

If this is the reason what is to do for getting a 'revisioncopy' for portfolio-items

Answer 1

The supports parameter for the post type has to ask for revisions.

Example:

register_post_type( 
    'portfolio', 
    array( 
        'supports' => array ( 'revisions' ) 
    ) 
);