Medium : Drupal 8, Typescript, React and i18n - locale.module

locale.module

/**
 * Implements hook_js_alter().
 */
function locale_js_alter(&$javascript, AttachedAssetsInterface $assets) {

  // ...
  
  // Replace the placeholder file with the actual JS translation file.
  $placeholder_file = 'core/modules/locale/locale.translation.js';
  if (isset($javascript[$placeholder_file])) {
    if ($translation_file = locale_js_translate($files)) {
      $js_translation_asset = &$javascript[$placeholder_file];
      $js_translation_asset['data'] = $translation_file;
      // @todo Remove this when https://www.drupal.org/node/1945262 lands.
      // Decrease the weight so that the translation file is loaded first.
      $js_translation_asset['weight'] = $javascript['core/misc/drupal.js']['weight'] - 0.001;
    }
    
    // ...
    
  }
}