mixed.test function, this.options.originalValue, should i use it?

[gabor]

i'm trying to validate a number-field, and to make sure it only contains a number (the default validator accepts things like "42haha". i did something like this:

const schema = yup.object().shape({
    num: yum.number().integer.required().test('foo', 'must-be-num', function(value) {
                    const orig = this.options.originalValue;
                    return value.toString() === orig.toString();
              }),
});

the question is, is the this.options.originalValue guaranteed to be there? i could not find anything about it in the documentation.

the this.options field only says:
the options object that validate() or isValid() was called with

validate says:

Options = {
  strict: boolean = false;
  abortEarly: boolean = true;
  stripUnknown: boolean = false;
  recursive: boolean = true;
  context: ?object;
}

so no info about the originalValue thing.

i'd just like to make sure i am using something i am supposed to use, and not some internal detail that can change with the next version.
alternatively, if there is a simpler way to achieve stricter number-validation, or a simpler way to get the originalValue in the test, please tell me.

[shellscape]

@jquense why was this closed without a response? Ran into the same thing today and was searching the issues for an answer.