I have a component and a test which fails. I get the error ReferenceError: act is not defined. Any idea for a fix? I've been trying to read around and fix this myself but I havent yet managed to.

export const useCounter = (initialValue = 0) => {
  const [counter, setCounter] = useState(initialValue)

  const add = useCallback((delta = 1) => setCounter(counter => counter + delta), [setCounter])
  const substract = useCallback((delta = 1) => setCounter(counter => counter - delta), [setCounter])

  return (
    <>
      Count: {counter}
      {add, substract}
    </>
  )
}

import { renderHook } from '@testing-library/react-hooks'
import { useCounter } from '@/hooks/useCounter'

describe('Testing useCounter hook', () => {

  it('should add +1 to counter', () => {
    const { result } = renderHook(useCounter)

    act(() => result.current.add())
    expect(result.current.counter).toBe(1)
  })

  it('should subtract -1 to counter', () => {
    const { result } = renderHook(useCounter)

    act(() => result.current.subtract())
    expect(result.current.counter).toBe(-1)
  })
})