get current value on yup when condition

Question

I have two date fields, start date, and end date. I would like to know how to set up a validation not to accept the start date to be higher than the end date and vice-versa.

Reading the yup documentation I saw the when condition, but it just gets values from other fields!

import { date, object } from 'yup';

export const yupSchema = object({
  startAt: date().typeError('Invalid date').nullable(),
  endAt: date().typeError('Invalid date').nullable(),
});

Answer 1

You can utilize ref's - no when required.

Example code:

const validationSchema = Yup.object().shape({
    arrivalDate: Yup.date().required(),
    departureDate: Yup.date().required().min(Yup.ref('arrivalDate'), 'Departure date must be after arrival date')})

Last time I checked when does not receive the current value, only the value of the sibling field you're checking. See this issue on Github where someone asked this exact question.