How can I restore posts from 'trash' with their previous post_status? - Wordpress

Question

I have a Custom post type in wordpress in which when creating a new post 3 child subposts are created automatically. For example, I create the post and assign it some status 'Publish', 'pending', 'draft' or another:

Post Company 1

-Subpost 1 (it is created automatically)  
-Subpost 2 (it is created automatically)  
-Subpost 3 (it is created automatically)

Removing the parent (moves to 'trash' ) will also remove the subposts. But when you restore them, they should be in the state they were saved in before ('pending', 'draft', 'auto-draft' or something else).

How could I do that to restore the posts (parent and children) with their 'post-status' that they had defined before being moved to 'trash'?

This is my code that I am using to create the 3 child subposts automatically:

function add_children_custom_post_type( $post_id ) {
if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE )
    return;

if ( !wp_is_post_revision( $post_id ) && 'companies' == get_post_type( $post_id ) && 'publish' == get_post_status( $post_id ) ) {
    $show = get_post( $post_id );
    if( 0 == $show->post_parent ){
        $children =& get_children(
            array(
                'post_parent' => $post_id,
                'post_type' => 'companies'
            )
        );
        if( empty( $children ) ){
            //Children pages
            $titles = ['Subpost1', 'Subpost2', 'Subpost3'];
            foreach ($titles as $key=>$title) {
                $child = array(
                    'post_type' => 'companies',
                    'post_title' => $title,
                    'post_content' => '',
                    'post_status' => 'publish',
                    'post_parent' => $post_id,
                    'post_author' => get_post_field('post_author', $post_id),
                    'menu_order' => $key
                );
                wp_insert_post( $child );
            }
        }
     }
  }
}
add_action( 'save_post', 'add_children_custom_post_type' );

And this is the one I use to move the child posts of a parent post when the parent is deleted:

// Move to Trash
function trash_post_children($post_id) {
$parent_ID = $post_id;

$args = array(
    'post_type' => 'companies',
    'post_parent' => $parent_ID,
    'posts_per_page' => -1,
    'post_status' => array('publish', 'pending', 'draft', 'auto-draft', 'future', 'private', 'inherit', 'trash')
);
  $children = get_posts($args);
  if($children) {
      foreach($children as $p){
        wp_trash_post($p->ID, true);
      }
   }
}
add_action('trashed_post', 'trash_post_children');

And this other one is to restore the posts but they are always restored in 'draft' state:

// RestorePost
function restore_post_children($post_id) {
   $parent_ID = $post_id;
    $args = array(
       'post_type' => 'companies',
       'post_parent' => $parent_ID,
       'posts_per_page' => -1,
       'post_status' => 'trash'
   );
   $children = get_posts($args);
   if($children) {
    foreach($children as $p) {
        wp_untrash_post($p->ID);
    }
  }
}
add_action('untrash_post', 'restore_post_children');

Answer 1

The reason it is a draft, and what you need to do to get what you wanted is spelt out in the source code for wp_untrash_post and in the documentation for wp_untrash_post_status:

https://github.com/WordPress/WordPress/blob/bbf017e550b02f5d11e409b07e689d45c984054d/wp-includes/post.php#L3668-L3685

    $new_status = ( 'attachment' === $post->post_type ) ? 'inherit' : 'draft';

    /**
     * Filters the status that a post gets assigned when it is restored from the trash (untrashed).
     *
     * By default posts that are restored will be assigned a status of 'draft'. Return the value of `$previous_status`
     * in order to assign the status that the post had before it was trashed. The `wp_untrash_post_set_previous_status()`
     * function is available for this.
     *
     * Prior to WordPress 5.6.0, restored posts were always assigned their original status.
     *
     * @since 5.6.0
     *
     * @param string $new_status      The new status of the post being restored.
     * @param int    $post_id         The ID of the post being restored.
     * @param string $previous_status The status of the post at the point where it was trashed.
     */
    $post_status = apply_filters( 'wp_untrash_post_status', $new_status, $post_id, $previous_status );

https://developer.wordpress.org/reference/hooks/wp_untrash_post_status/

By default posts that are restored will be assigned a status of ‘draft’. Return the value of $previous_status in order to assign the status that the post had before it was trashed. The wp_untrash_post_set_previous_status() function is available for this.

Prior to WordPress 5.6.0, restored posts were always assigned their original status.

So use that filter and add wp_untrash_post_set_previous_status to it which was built specifically for this problem: https://developer.wordpress.org/reference/functions/wp_untrash_post_set_previous_status/

Notice its source code is super simple