A bite of bits

// @todo Merge with wp_delete_user() ?

Like they suggest in their comment the wpmu_delete_user function is not ready yet. When deleting a user, WordPress does not allow you to reassign the user’s content to another user. My rewrite below is a merge with the wp_delete_user that lets you do so.

function wpmu_delete_user($id, $reassign) {
    global $wpdb;

    $id = (int) $id;

    do_action( 'wpmu_delete_user', $id );

    $blogs = get_blogs_of_user( $id );

    if ( ! empty( $blogs ) ) {
        foreach ( $blogs as $blog ) {
            switch_to_blog( $blog->userblog_id );
            remove_user_from_blog( $id, $blog->userblog_id );

            if ( 'novalue' === $reassign || null === $reassign ) {
                $post_ids = $wpdb->get_col( $wpdb->prepare("SELECT ID FROM $wpdb->posts WHERE post_author = %d", $id) );

                if ( $post_ids ) {
                    foreach ( $post_ids as $post_id )
                        wp_delete_post($post_id);
                }

                // Clean links
                $link_ids = $wpdb->get_col( $wpdb->prepare("SELECT link_id FROM $wpdb->links WHERE link_owner = %d", $id) );

                if ( $link_ids ) {
                    foreach ( $link_ids as $link_id )
                        wp_delete_link($link_id);
                }
            } else {
                $reassign = (int) $reassign;
                $wpdb->update( $wpdb->posts, array('post_author' => $reassign), array('post_author' => $id) );
                $wpdb->update( $wpdb->links, array('link_owner' => $reassign), array('link_owner' => $id) );
            }

            restore_current_blog();
        }
    }

    // FINALLY, delete user
    $wpdb->query( $wpdb->prepare("DELETE FROM $wpdb->usermeta WHERE user_id = %d", $id) );
    $wpdb->query( $wpdb->prepare("DELETE FROM $wpdb->users WHERE ID = %d", $id) );

    clean_user_cache( $id );

    // allow for commit transaction
    do_action( 'deleted_user', $id );

    return true;
}

I think it would be even better to use the wp_delete_user function in this function instead of just copying the code, by doing that the hooks would be triggered for each blog which would allow each’s plugins to do their thing.