Currently the OptionsResolver performs filtering before validating.
Which is kind of weird.

When I set an value that can only be an string or null the filtering is performed before the actual type validating.
So I still need to check in my filtering function whether the input value is accepted and throw an exception (with not to much information as that is not available), second when my filtering function returns something else like an object I get an error because type does not match.

Should it be better to perform type validation before performing filtering or add an different method for adding validations that will be performed bore filtering?