Yup schema validation: Exclude a certain pattern in the method '.matches()'

Question

I want to make sure users don't fill in their username (pattern is a upercase or lowercase u, followed by 7-10 digits: U0000000)

In the following example, the regex itself does work. However in conjunction with the .matches() method it does not validate the field.

const schema = Yup.object()
  .shape({
    myField: Yup.string()
      .matches(/.*\d/, 'Should contain a digit') // <- this works
      .matches(/(?!.*[uU]\d{7,10})/, 'Should not contain a user ID') // <- this does not
  });

@WiktorStribiżew It's more a Yup schema question. The regex pattern works fine outside of the schema. — Remi, Dec 10 '19 at 13:57
Doesn't `/^(?!.*[uU]\d{7,10})/` or `/^(?!.*[uU]\d{7,10}).*/` work? — Wiktor Stribiżew, Dec 10 '19 at 14:00
Yes and no. Yes, that would filter out the user id. No: It doesn't work in conjunction with the .matches() method. But I've found the answer after some time. I can add it if you'd reopen this question again. — Remi, Dec 11 '19 at 07:32
I've also editted the question to make it more clear since it seems that it wasn't clear. — Remi, Dec 11 '19 at 07:34

Remi · Accepted Answer · 2019-12-12T14:01:23.130

Turns out that matches will only validate an invalid error if the Regex you provide returns positive.

If you want to validate on a negative 'match', you can use the .test() method.

In the documentation it's not mentioned under string, but under mixed (source):

mixed.test(name: string, message: string | function, test: function): Schema

So in my example I ended up with:

const containsDeviceId = (string) => /d\d{7,10}/.test(string);
const schema = Yup.object()
  .shape({
    myField: Yup.string()
      .matches(/.*\d/, 'Should contain a digit')
      .test(
        'Should not contain a user ID',
        'Should not contain a user ID',
        (value) => !containsDeviceId(value)
      ),

Hope this helps someone.

`/(?=.*[dD]\d{7,10})/` can be simplified to `/d\d{7,10}/i` – Wiktor Stribiżew Dec 12 '19 at 09:53 — Wiktor Stribiżew, Dec 12 '19 at 09:53

Yup schema validation: Exclude a certain pattern in the method '.matches()'

1 Answers1