code: public function get_source_to_enqueue( $relative_path, $filename, $filename_debug = null ) {
  
          $source_file = $filename;
  
          if ( defined( 'SCRIPT_DEBUG' ) && true === SCRIPT_DEBUG && !empty( $filename_debug ) ) {
  
              $source_file = $filename_debug;
  
          }
  
          $path = realpath( trailingslashit( $relative_path ) . $source_file );
  
          return WP_Url_Util::get_instance()->convert_absolute_path_to_url( $path );
  
      }
docs: Gets the source to enqueue based upon whether or not debugging is enabled.
  
  @param $relative_path string Relative path to the potential files to enqueue.
  @param $filename string Filename of the production file to enqueue.
  @param $filename_debug string Filename of the file to enqueue when debugging.
  @return string A url to the source to enqueue.