Moving fields with different shapes, some fields' functions gone

[ArnoZx]

Are you submitting a bug report or a feature request?

Bug report

What is the current behavior?

After moving fields with different shapes, some fields' change, blur and focus functions were gone.

What is the expected behavior?

Maybe these functions should be restored or recreated.

test case below would fail with TypeError: state.fields.foo[1].cat.change is not a function

it('should preserve functions in field state when fields with different shapes', () => {
  // implementation of changeValue taken directly from Final Form
  const changeValue = (state, name, mutate) => {
    const before = getIn(state.formState.values, name)
    const after = mutate(before)
    state.formState.values = setIn(state.formState.values, name, after) || {}
  }
  const state = {
    formState: {
      values: {
        foo: [{ dog: 'apple dog', cat: 'apple cat' }, { dog: 'banana dog' }]
      }
    },
    fields: {
      'foo[0].dog': {
        name: 'foo[0].dog',
        touched: true,
        error: 'Error A Dog',
        change: () => 'A Dog'
      },
      'foo[0].cat': {
        name: 'foo[0].cat',
        touched: false,
        error: 'Error A Cat',
        change: () => 'A Cat'
      },
      'foo[1].dog': {
        name: 'foo[1].dog',
        touched: true,
        error: 'Error B Dog',
        change: () => 'B Dog',
      }
    }
  }
  move(['foo', 0, 1], state, { changeValue })
  expect(state.formState).toMatchObject({values: {
    foo: [{ dog: 'banana dog' }, { dog: 'apple dog', cat: 'apple cat' }]
  }})
  expect(state.fields['foo[0].dog'].change()).toBe('A Dog')
  expect(state.fields['foo[1].dog'].change()).toBe('B Dog')
  
  // this expect would fail with `TypeError: state.fields.foo[1].cat.change is not a function`
  expect(state.fields['foo[1].cat'].change()).toBe('A Cat')
})

What's your environment?

"final-form-arrays": "3.0.2",

Other information

[SeqviriouM]

I have the same bug with unshift method.