indexUpdater.addClickCountField(doc);

        assertNull(doc.get("click_count"));
    }

    // Test addClickCountField with blank URL
    public void test_addClickCountField_blankUrl() {
        final Map<String, Object> doc = new HashMap<>();
        doc.put("url", "   ");

        indexUpdater.addClickCountField(doc);

        assertNull(doc.get("click_count"));
    }