handleSubmit/trigger resets fieldState of unmounted field

[joeldotsh]

Description

I'm seeing odd behavior that doesn't seem right.. I have a form (with shouldUnregister: false) with fields that are dynamically shown/hidden (unmounted) based on a radio button.

When toggling the radio button, I see the fields render as expected - they hold their previous values and state. But when I submit (and there are errors so it doesn't proceed), their values are retained but their state is reset (in particular the error state).

I would expect their state to be retained - which, again, does happen when toggling the fields on and off before submission.

This happens when manually invoking trigger as well.

CSB

https://codesandbox.io/s/flamboyant-lederberg-cx9ve8?file=/src/App.js

Steps to reproduce

1. Click Toggle Last Name
2. Click Submit
3. Observe error on both First Name and Last Name fields
4. Click Toggle Last Name
5. Observe error on First Name field
6. Click Submit
7. Click Toggle Last Name
8. Observe no error on Last Name field

Expected: After step 7, there should still be an error on Last Name field

Env

• Desktop macOS Monterey 12.3
• Chrome/FF (113/113)

Am I doing something wrong? Am I thinking about this wrong? Any insight is appreciated.

Thank you