I have a form with 2 checkboxes - the constraint is that a max of 1 of the checkboxes can be checked. In other words, both checkboxes can't be checked.

I have added logic to the form to disable the other checkbox when 1 is checked. But I'd also like to validate this.

My attempt was this:

yup.object().shape({
  textInput: yup.string().trim().required('Text input is required.'),
  checkbox1: yup.boolean()
    .when('checkbox2', {
      is: true,
      then: yup.boolean().isFalse()
    }),
  checkbox2: yup.boolean()
    .when('checkbox1', {
      is: true,
      then: yup.boolean().isFalse()
    }),
}, [[ 'checkbox1', 'checkbox2' ]])

But this causes strange behavior - it seems to return a false validation when the first is checked, and then the second is checked. But doesn't return a false validation if the second is checked, and then the first is checked.

Is it possible to do a validation like this?