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import { sort } from './sort.js'
const fn = (a, b) => a > b ? 1 : -1
test('sort', () => {  expect(sort((a, b) => a - b)([ 2, 3, 1 ])).toEqual([ 1, 2, 3 ])})
test('it doesn\'t mutate', () => {  const list = [ 'foo', 'bar', 'baz' ]
  expect(sort(fn, list)).toEqual([ 'bar', 'baz', 'foo' ])
  expect(list[ 0 ]).toBe('foo')  expect(list[ 1 ]).toBe('bar')  expect(list[ 2 ]).toBe('baz')})