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import { isFunction } from './isFunction'
test('when function', () => {  const fn = () => {}
  expect(isFunction(fn)).toEqual(true)})
test('when promise', () => {  const fn = Promise.resolve(2)
  expect(isFunction(fn)).toBeFalse()})
test('when async', () => {  const fn = async x => x
  expect(isFunction(fn)).toEqual(true)})
test('when false', () => {  expect(isFunction(null)).toEqual(false)})