issue: useFieldArray doesn't retain provided values when appending

[abnerey]

Version Number

^7.30.0

Codesandbox/Expo snack

https://stackblitz.com/edit/vitejs-vite-qcckuk

Steps to reproduce

1. Go to https://stackblitz.com/edit/vitejs-vite-qcckuk
2. See how the first two rows have changed their uniqueId (which is the keyName)
3. Add new rows
4. See how uniqueIds get overwritten by RHF

Expected behaviour

I saw that from version 7.23.0 ids are retained by RHF, but this only works for the default keyName, I consider that it makes sense to retain values on the provided keyName too so overrides can be avoided.

What browsers are you seeing the problem on?

No response

Relevant log output

No response

Code of Conduct

• I agree to follow this project's Code of Conduct

[bluebill1049]

use keyName to change the id

[abnerey]

What I'm looking for is to useFieldArray to preserve the original values of whatever keyName was given, either default or custom, that's how it works currently when you use the default one (refer to the screenshot)

And the thing is that in the project I have we need to control the keyName outside of RHF

If it breaks something it can be a useFieldArray config property to avoid breaking changes or unexpected behaviours for current lib consumers