How to have typescript correctly infer the type for a custom type schema?

I have the following:

import * as yup from 'yup'
import Daet from 'daet'

class daetSchema extends yup.date {
	constructor() {
		super()
		this.withMutation(() => {
			this.transform(function(value, originalvalue) {
				if (this.isType(value)) return value
				return new Daet(value)
			})
		})
	}

	_typeCheck(value: any) {
		// @ts-ignore
		return super._typeCheck(value) || value instanceof Daet
	}
}

export const mySchema = yup.object({
	start: new daetSchema()
		.label('Start Time')
		.max(yup.ref('finish'))
		.required()
})
export type MySchema = yup.InferType<typeof mySchema>

However the types are coming back with Date:

const mySchema: yup.ObjectSchema<{
    start: Date;
}>
type MySchema = {
    start: Date;
}

How do I correct their types so they come back with Daet:

const mySchema: yup.ObjectSchema<{
    start: Daet;
}>
type MySchema = {
    start: Daet;
}

[rizkimcitra]

same issue here, is there any update?

[balupton]

does that help?

Not sure what foo, bar, baz, subschema, and o are meant to represent here…

Essentially, all I need is for Yup to work with https://github.com/bevry/daet instances