assertThrows(
        IllegalArgumentException.class,
        () -> Types.newArtificialTypeVariable(List.class, "E", int.class));
  }

  public void testNewTypeVariable_serializable() throws Exception {
    assertThrows(
        RuntimeException.class,
        () -> SerializableTester.reserialize(Types.newArtificialTypeVariable(List.class, "E")));
  }