bug: allOf when an element is a oneOf union generates an invalid zod schema

[mnahkies]

Given a schema like:

components:
  schemas:
    Example:
      allOf:
        - oneOf:
            - type: object
              properties:
                foo:
                  type: string
            - type: object
              properties:
                bar:
                  type: string
        - type: object
          properties:
            id:
              type: string

Which produces the type:

export type t_Example = (
  | {
      foo?: string
    }
  | {
      bar?: string
    }
) & {
  id?: string
}

We get an invalid zod schema, as .merge isn't supported by ZodUnion

[mnahkies]

Note: this is also an issue with the joi schema builder.

[mnahkies]

Fixed for zod by #283, still an issue for joi (hapijs/joi#3057) but going to leave this as a known issue / todo in the code for now.