}

    @Test
    public void test_jsonFormatter_controlCharacters() {
        final Map<String, Object> source = new LinkedHashMap<>();
        source.put("text", "back\bfeed\freturn\r");

        final String json = new JsonIndexExportFormatter().format(source, Collections.emptySet());

        assertTrue(json.contains("\\b"));
        assertTrue(json.contains("\\f"));