Why are yup errors not being reported by trigger on an array field.

[chandu]

The trigger method is not reporting that form is invalid when we are binding a model with an array property and if the property is not populated.
e.g:

interface Person {
  name: string;
}

interface Persons {
  persons: Person[];
}

const personsValidator = yup.object<Persons>({
  persons: yup
    .array<Person>()
    .required()
    .min(1)
});

When I am binding the model mentioned above to RHF and am using useFieldArray hook to render the persons property.
When I call trigger without adding any person to the fields, RHF is validating the model successfully.
But the yup validator I have defined above marks persons field as required.

When I validate the model calling the yup validator directly, it is performing the validation correctly.

Steps to reproduce the behavior:

1. Click on Validate Directly button, Direct Validation Message: ValidationError: persons is a required field is shown
2. Click on 'Validate via RHF', RHF Trigger Message: Is Valid: true is shown. But I expect RHF's trigger to actually return an error saying ValidationError: persons is a required field
   Why is RHF not repoting the error?

I expect the validation result either via yup or the rhf trigger (which is using the yupResolver) to be the same but here they are incosistent.

Codesandbox
https://codesandbox.io/s/dynamic-fields-validation-iiiso

**Browser ; Chrome

• Version: 6.1.2/6.2.0

[chandu]

I guess the issue stems from this line:
https://github.com/react-hook-form/react-hook-form/blob/master/src/useForm.ts#L351 here we are only validating the fields that are in fieldRef.

[bluebill1049]

hey @chandu no worries, what do you mean by not include errors object?

[chandu]

In the example at: https://codesandbox.io/s/dynamic-fields-validation-iiiso I don't get the error: 'Atleast one entry by name BATMAN should be present' in the errors object.

How can I get the errors object populate this message and also avoid calling yup.validate explicitly?

[bluebill1049]

any chance you can add a rule for empty object check at yup? otherwise, you will have to use shouldUnregister: false

[chandu]

@bluebill1049 Thanks. I applied the changes you have suggested and can see that the persons object is now populated with the error message. However trigger method is still passing the test. Anyway to make it report the validation failed?
CSB: https://codesandbox.io/s/dynamic-fields-validation-forked-usx8b

[bluebill1049]

can you inspect why there are no errors? you can console log at the resolver against the schema. trigger is basically run through the resolver