return 2.5f;
            }
        };
        indexUpdater.addDocBoostMatcher(matcher);

        indexUpdater.updateDocument(doc);

        assertEquals(2.5f, doc.get("boost"));
        assertNotNull(doc.get("doc_id"));
    }

    // Test updateDocument without boost
    @Test
    public void test_updateDocument_withoutBoost() {
        final Map<String, Object> doc = new HashMap<>();

        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);

        assertEquals("ja", doc.get("lang"));
        assertEquals("タイトル", doc.get("title_ja"));
        assertEquals("コンテンツ", doc.get("content_ja"));
    }

    @Test