field with Types.ObjectId has typescript error in Schema

Prerequisites

• I have written a descriptive issue title

Mongoose version

6.5.4

Node.js version

16.14.2

MongoDB version

doesn’t matter

Operating system

macOS

Operating system version (i.e. 20.04, 11.3, 10)

12.5.1

Issue

import { Schema, Types } from 'mongoose';

interface Foo {
  _id: Types.ObjectId,
  bar: Types.ObjectId,
}

const FooSchema = new Schema<Foo>({
  _id: { type: Types.ObjectId },
  bar: { type: Types.ObjectId },
});

property _id and bar has typescript error:

Type '{ type: typeof Types.ObjectId; }' is not assignable to type 'SchemaDefinitionProperty<ObjectId> | undefined'.
  Types of property 'type' are incompatible.
    Type 'typeof ObjectId' is not assignable to type 'typeof Mixed | ObjectIdSchemaDefinition | undefined'.ts(2322)

But I cannot figure out why, and don’t know how to solve it.

[hasezoey]

sorry that i didnt see that before, but yes it seems like mongoose currently does not translate mongoose.Schema.Types.* to mongoose.Types.* in types and you have to use the latter for the types, but the former for the Schema itself (in new Schema(here))

[hasezoey]

I tried few things with HydratedDocument and LeanDocument but they don’t change the Schema.Types.ObjectId into Types.ObjectId. smiling_face_with_tear

the proper type should be type YourDocument = mongoose.Document<IdType> & YourSchema, also see Mongoose Documentation: Typescript

see typegoose’s implementation for a full (generic) example: https://github.com/typegoose/typegoose/blob/06f710df2d47a7501a496dc877dce955e047fe2b/src/types.ts#L14-L18

// the following is from typegoose, modified without typegoose-specific things
export type DocumentType<T, QueryHelpers = BeAnObject> = (T extends { _id: unknown }
  ? mongoose.Document<T['_id'], QueryHelpers, T>
  : mongoose.Document<any, QueryHelpers, T>) &
  T;