Creating union types from prismaObjects

[DerTimonius]

I'm working on a project that uses pothos in conjunction with Prisma. Currently, I need to implement a mutation that can return varying types depending on the input - in my case AnswerText or AnswerDate which are both prismaObjects.
Following the guide on unions I tried to implement a AnswerUnion type like this:

const AnswerUnion = builder.unionType('AnswerUnion', {
  types: [AnswerDate, AnswerText],
});

This is not showing any TypeScript errors at this level, but when I'm trying to use the type I'm getting errors stating that properties like modelName are missing, even if I add a resolveTypes function to the unionType.

Is it possible to create unionTypes out of prismaObjects or is it obligatory to use objectTypes in this case?

[hayes]

It's possible to create union types with prisma objects, but the query optimization won't work quite as well through unions. There is an undocumented trick you need to use with unions (documenting this better has been on my todo list for a while):

answers t.field({
  type: [AnswerUnion],
  resolve: async () => {
    const dates = getDateAnswers();
    const texts = getTextAnswers();
    return [...AnswerDate.addBrand(dates), ...AnswerText.addBrand(texts)];
  },
}),