@Test
public void validateFeatureThrowingStringNoUpdateOptionsOk() {

  OptionCollection.Builder existing = OptionCollection.newBuilder()
      .setOption(OptionType.string)
      .addItems(FeatureOption.newBuilder().setValue("red").setKey("opt-red").setWeight(3000).setId("r"))
      .addItems(FeatureOption.newBuilder().setValue("green").setKey("opt-green").setWeight(2000).setId("g"))
      .addItems(FeatureOption.newBuilder().setValue("blue").setKey("opt-blue").setWeight(5000).setId("b"));
  OptionCollection.Builder update = OptionCollection.newBuilder();
  try {
    new FeatureValidator().validateOptionIdsForUpdate(existing.build(), update.build());
  } catch (ServiceException e) {
    fail("an update without options should validate");
  }
}