Metro_Sitemap::check_year_has_posts PHP Method

    public static function check_year_has_posts()
    {
        $all_years = self::get_post_year_range();
        $years_with_posts = array();
        foreach ($all_years as $year) {
            if (self::date_range_has_posts(self::get_date_stamp($year, 1, 1), self::get_date_stamp($year, 12, 31))) {
                $years_with_posts[] = $year;
            }
        }
        return $years_with_posts;
    }

 /**
  * Generate full sitemap for site
  *
  * @subcommand generate-sitemap
  */
 function generate_sitemap($args, $assoc_args)
 {
     $this->command = 'all';
     $all_years_with_posts = Metro_Sitemap::check_year_has_posts();
     $sitemap_args = array();
     foreach ($all_years_with_posts as $year) {
         if ($this->halt_execution()) {
             delete_option('msm_stop_processing');
             break;
         }
         $sitemap_args['year'] = $year;
         $this->generate_sitemap_for_year(array(), $sitemap_args);
     }
 }