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")));
  }

    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")));
  }

    }
  }

  /**
   * Returns a new {@link TypeVariable} that belongs to {@code declaration} with {@code name} and
   * {@code bounds}.
   */
  static <D extends GenericDeclaration> TypeVariable<D> newArtificialTypeVariable(
      D declaration, String name, Type... bounds) {
    return newTypeVariableImpl(
        declaration, name, (bounds.length == 0) ? new Type[] {Object.class} : bounds);
  }