how can I use .extend or .merge with .lazy(() => z.object({ ... }))

[UNDERCOVERj]

as you can see，ZodType does not have extend，so how can I write the type for FormData

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[Profesor08]

Any news?

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[WesSouza]

Wow, closed as stale but this is a real scenario when you have complex lazy objects that might need extending.

I'm playing with ActivityPub and it is extremely nested. Zod seemed like a perfect fit because ActivityPub implementations are all over the place, and I want some sane validation, but the nesting makes things weird.

The crux of the problem here seems to be any object that extends a lazy object must be also lazy, and I'm not sure there's a nice way of enforcing this through zod's syntax.

I ended up exposing the lazy callback as part of the object:

// Object.ts
export type ObjectType = { ... }

export function lazyObjectSchema = () => {
  ...
  return { ... }
}

export const ObjectSchema: z.ZodType<ObjectType> = z.lazy(lazyObjectSchema);


// Document.ts
import { lazyObjectSchema, ObjectType } from "./object.js";

export type Document = ObjectType & {
  ...
};

export const DocumentSchema: z.ZodType<Document> = z.lazy(() =>
  lazyObjectSchema()
    .extend({
      ...
    }),
);

Hope this is helpful to anyone else landing here with nowhere else to go.