String result = languageHelper.getReindexScriptSource();
        assertEquals("if(ctx._source.lang!=null){ctx._source['title_'+ctx._source.lang]=ctx._source.title}", result);
    }

    public void test_getReindexScriptSource_multipleFields() {
        languageHelper.langFields = new String[] { "title", "content", "description" };

        String result = languageHelper.getReindexScriptSource();
        assertEquals(

        }
        return new Script(buf.toString());
    }

    /**
     * Returns the reindex script source.
     *
     * @return The reindex script source.
     */
    public String getReindexScriptSource() {
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final String langField = fessConfig.getIndexFieldLang();
        final String code = Arrays.stream(langFields)

                .replace("__SIZE__", fessConfig.getIndexReindexSize())//
                .replace("__DEST_INDEX__", toIndex)//
                .replace("__SCRIPT_SOURCE__", ComponentUtil.getLanguageHelper().getReindexScriptSource());
        return reindex(fromIndex, toIndex, source, waitForCompletion);
    }

    /**
     * Reindexes documents from one index to another.
     *