Inserted / pushed ArrayField is not pristine

[maciejmyslinski]

Are you submitting a bug report or a feature request?

bug report

What is the current behavior?

We have an array of fruits.
Initial values are: []

Steps to reproduce:

1. click insert(0, '') or push('') button.

When an Array Field mounts for the first time with insert or push, it's NOT pristine.

What is the expected behavior?

When a normal Field mounts for the first time, it's pristine. I would expect every inserted or pushed input to be pristine as well.

Sandbox Link

What's your environment?

package	version
final-form	4.11
react-final-form	4.0.2
final-form-arrays	1.1.1
react-final-form-arrays	2.0.1

Other information

[erikras]

This is not really a bug. If you insert(0, undefined) or push(undefined), they are pristine. That's how non-array fields appear pristine on first render. The way final-form handles '' and undefined is complex and intentional.