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import {reverse} from './reverse.js'
test('happy', () => {  expect(reverse([1, 2, 3])).toEqual([3, 2, 1])})
test('with string', () => {  expect(reverse('baz')).toBe('zab')})
test("it doesn't mutate", () => {  const arr = [1, 2, 3]
  expect(reverse(arr)).toEqual([3, 2, 1])
  expect(arr).toEqual([1, 2, 3])})