DocMap docMap = new DocMap(parentMap);

        assertNotNull(docMap);
        assertTrue(docMap.isEmpty());
        assertEquals(0, docMap.size());
    }

    @Test
    public void test_basic_operations() {
        Map<String, Object> parentMap = new HashMap<>();
        DocMap docMap = new DocMap(parentMap);

        docMap.put("key1", "value1");
        docMap.put("key2", 123);
        docMap.put("key3", true);