public static YamlMapAccessor empty() {
        return new YamlMapAccessor(new LinkedHashMap<>());
    }
@Test
    public void testEmpty() {
        YamlMapAccessor yamlMapAccessor = YamlMapAccessor.empty();
        Optional<Object> optional = yamlMapAccessor.get("/");
        assertNotNull(optional);
        assertTrue(optional.isPresent());
        assertTrue(optional.get() instanceof Map);
        Map<Object, Object> map = (Map<Object, Object>) optional.get();
        assertTrue(map.isEmpty());

        optional = yamlMapAccessor.getOrCreate("/foo", () -> new LinkedHashMap<>());
        assertNotNull(optional);
        assertTrue(optional.isPresent());
        assertTrue(optional.get() instanceof Map);
        map = (Map<Object, Object>) optional.get();
        map.put("value", 1);

        optional = yamlMapAccessor.get("/foo/value");
        assertNotNull(optional);
        assertTrue(optional.isPresent());
        assertNotNull(optional.get());
        assertTrue(optional.get() instanceof Integer);
        assertEquals(1, ((Integer) optional.get()).intValue());

        optional = yamlMapAccessor.get("/foo");
        assertNotNull(optional);
        assertTrue(optional.isPresent());
        assertTrue(optional.get() instanceof Map);
        map = (Map<Object, Object>) optional.get();
        assertTrue(map.get("value") instanceof Integer);
        assertTrue(((Integer) map.get("value")) == 1);
    }