code: function addTextLocale(locale, body, options = {}) {
    const gt = new Gettext();
    const domain = 'messages';
    const {
      filter,
      gettextDefaultCharset = 'UTF-8',
    } = options;
  
    if (body.length > 0) {
      gt.addTranslations(locale, domain, po.parse(body, gettextDefaultCharset));
    }
  
    if (filter) {
      const filterAsync = Promise.promisify(filter);
      return filterAsync(gt, locale);
    }
  
    return Promise.resolve(gt.catalogs[locale] && gt.catalogs[locale][domain].translations);
  }
docs: /*
  gettext --> barebone json