date field validation bug

Describe the bug When yup.date() field gets empty string for validation, it throws error even if field is nullable or not required.

ValidationError: required must be a date type, got: “Invalid Date” instead

To Reproduce https://runkit.com/michal-de/yup-date-bug

Expected behavior Empty string case should be considered as null or undefined.

Platform (please complete the following information):

• Browser: chrome
• Version: 79.0.3945.130 (Official Build) (64-bit)]

Additional context Empty string is default html input value for type date or datetime-local.

[lucasconstantino]

Fixed with nullable and transform, to avoid polluting the input/html code:

const schema = Yup.date()
  .nullable()
  .transform((curr, orig) => orig === '' ? null : curr)
  .required('Mandatory field message')

[rexebin]

@4ortytwo you can customize the error message via typeError.

yearEndDate: date().nullable().typeError('Invalid Date') works like dream.