t.Fatalf("Blog should has three tags after Append")
	}

	if count := DB.Model(&blog).Association("Tags").Count(); count != 3 {
		t.Fatalf("Blog should has 3 tags after Append, got %v", count)
	}

	var tags []Tag
	DB.Model(&blog).Association("Tags").Find(&tags)
	if !compareTags(tags, []string{"tag1", "tag2", "tag3"}) {
		t.Fatalf("Should find 3 tags")
	}

	var blog1 Blog
	DB.Preload("Tags").Find(&blog1)

        String[] fields = { "field1", "field2" };
        item.setFields(fields);
        assertArrayEquals(fields, item.getFields());

        // Test tags
        String[] tags = { "tag1", "tag2" };
        item.setTags(tags);
        assertArrayEquals(tags, item.getTags());

        // Test roles
        String[] roles = { "admin", "user" };
        item.setRoles(roles);

        readings[1] = new String[] { "enjin", "fuga" };
        String[] tags = new String[] { "tag1", "tag2" };
        String[] roles = new String[] { SuggestConstants.DEFAULT_ROLE, "role1", "role2", "role3" };
        queryItems[0] = new SuggestItem(new String[] { "検索", "エンジン" }, readings, new String[] { "content" }, 1, 0, -1, tags, roles, null,
                SuggestItem.Kind.DOCUMENT);

 */
internal sealed class Tags {
  /**
   * Returns a tags instance that maps [key] to [value]. If [value] is null, this returns a tags
   * instance that does not have any mapping for [key].
   */
  abstract fun <T : Any> plus(
    key: KClass<T>,
    value: T?,
  ): Tags

  abstract operator fun <T : Any> get(key: KClass<T>): T?
}

/** An empty tags. This is always the tail of a [LinkedTags] chain. */

            "limit": 10,
            "offset": 5,
            "order_by": "updated_at",
            "tags": ["tag1", "tag2"],
        },
    )
    assert response.status_code == 200
    assert response.json() == {
        "limit": 10,
        "offset": 5,
        "order_by": "updated_at",
        "tags": ["tag1", "tag2"],
    }


def test_query_param_model_defaults(client: TestClient):

        "price": 50.2,
        "tax": 10.5,
        "tags": [],
    }


def test_patch_all(client: TestClient):
    response = client.patch(
        "/items/foo",
        json={
            "name": "Fooz",
            "description": "Item description",
            "price": 3,
            "tax": 10.5,
            "tags": ["tag1", "tag2"],
        },
    )
    assert response.json() == {

            "limit": 10,
            "offset": 5,
            "order_by": "updated_at",
            "tags": ["tag1", "tag2"],
        },
    )
    assert response.status_code == 200
    assert response.json() == {
        "limit": 10,
        "offset": 5,
        "order_by": "updated_at",
        "tags": ["tag1", "tag2"],
    }


def test_query_param_model_defaults(client: TestClient):

        List<String> fields = Arrays.asList("field1", "field2");
        List<String> tags = Arrays.asList("tag1", "tag2");
        List<String> roles = Arrays.asList("role1", "role2");

        elevateWord = new ElevateWord(word, boost, readings, fields, tags, roles);

        assertEquals(word, elevateWord.getElevateWord());
        assertEquals(boost, elevateWord.getBoost(), 0.001f);

        assertNotNull(dataMap);
        assertTrue(dataMap.get("tags") instanceof List);
        @SuppressWarnings("unchecked")
        List<String> tags = (List<String>) dataMap.get("tags");
        assertEquals(3, tags.size());
        assertEquals("tag1", tags.get(0));
        assertEquals("tag2", tags.get(1));
        assertEquals("tag3", tags.get(2));
    }

        .plus(Boolean::class, null)
    assertThat(tags).isEqualTo(EmptyTags)
    assertThat(tags.toString()).isEqualTo("{}")
  }

  @Test
  fun removeAbsentFromEmpty() {
    val tags = EmptyTags.plus(String::class, null)
    assertThat(tags).isEqualTo(EmptyTags)
    assertThat(tags.toString()).isEqualTo("{}")
  }

  @Test
  fun removeAbsentFromNonEmpty() {
    val tags =
      EmptyTags