[Solved] wpdumc_user_search_result

/**
 * Filters the list of mentionable users to only include users with the 'diocesan_admin' role.
 *
 * This function hooks into the `wpdumc_user_search_result` filter provided by the
 * wpDiscuz User & Comment Mentioning add-on. It restricts the user search results
 * so that only users with the custom role 'diocesan_admin' are returned based on the search term.
 *
 * @param array  $users       The original list of users returned by wpDiscuz.
 * @param int    $post_id     The ID of the current post where the mention is used.
 * @param string $search_term The term entered after the '@' symbol to search users.
 *
 * @return array $filtered_users Filtered list of users who have the 'diocesan_admin' role.
 */

add_filter('wpdumc_user_search_result', 'filter_diocesan_admin_mentions', 10, 3);

function filter_diocesan_admin_mentions($users, $post_id, $search_term) {
    $filtered_users = [];

    $args = [
       'role'    => 'diocesan_admin',
       'search'  => '*' . esc_attr($search_term) . '*',
       'search_columns' => ['user_login', 'display_name'],
       'fields'  => ['ID', 'display_name', 'user_login', 'user_nicename']
    ];

    $diocesan_users = get_users($args);

    foreach ($diocesan_users as $user) {
       $filtered_users[] = (object)[
          'ID'            => (string)$user->ID,
          'display_name'  => $user->display_name,
          'value'         => $user->user_nicename,
          'user_nicename' => $user->user_nicename,
          'avatar'        => "<div class='ucm-avatar'>" . get_avatar($user->ID, 30) . "</div>"
       ];
    }

    return $filtered_users;
}