// Should not throw exception
        } catch (Exception e) {
            fail("init() should not throw an exception: " + e.getMessage());
        }
    }

    @Test
    public void test_updateDocument_withExistingLang() {
        Map<String, Object> doc = new HashMap<>();
        doc.put("lang", "ja");
        doc.put("title", "タイトル");
        doc.put("content", "コンテンツ");

        languageHelper.updateDocument(doc);