Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the bug has not already been reported

Mongoose version

8.20.1

Node.js version

20.x

MongoDB server version

5.x

Typescript version (if applicable)

5.9.3

Description

Using the Schema.static method to set static model methods requires all methods to be passed. The current type definition is
(

This also causes problems with writing a generic Schema type.

Steps to Reproduce

Test:

interface IDoc {
}

interface DocStatics {
	m1(): void;
	m2(): void;
}

const schema = new Schema<IDoc, Model<IDoc>, {}, {}, {}, DocStatics>({});
schema.static({ m1() {} }); //TS Error. Property m2 missing

For the second observation consider

schema satisfies Schema<any, Model<any>, {}, {}, {}, {}>;

This might fail for other reasons as well, but part of the problem is that {} is missing the properties in DocStatics, making the static function unassignable to it's "generic" counterpart. Even when using an index signature e.g. { [name: string]: () => never } the check will still fail because index signature properties are considered optional. If the

Expected Behavior

No error.

The should allow defining the statics one by one as with Schema.method where the parameter is obj: Partial<TInstanceMethods>.
In this case the type thus should be

static(obj: { [F in keyof TStaticMethods]?: TStaticMethods[F] } & { [name: string]: (this: TModelType, ...args: any[]) => any }): this;

notice the added ? to make the keys optional.