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import { update } from './update.js'
const list = [ 1, 2, 3 ]
test('happy', () => {  const newValue = 8  const index = 1  const result = update(    index, newValue, list  )  const curriedResult = update(index, newValue)(list)  const tripleCurriedResult = update(index)(newValue)(list)
  const expected = [ 1, 8, 3 ]  expect(result).toEqual(expected)  expect(curriedResult).toEqual(expected)  expect(tripleCurriedResult).toEqual(expected)})
test('list has no such index', () => {  const newValue = 8  const index = 10  const result = update(    index, newValue, list  )
  expect(result).toEqual(list)})
test('with negative index', () => {  expect(update(    -1, 10, [ 1 ]  )).toEqual([ 10 ])  expect(update(    -1, 10, []  )).toEqual([])  expect(update(    -1, 10, list  )).toEqual([ 1, 2, 10 ])  expect(update(    -2, 10, list  )).toEqual([ 1, 10, 3 ])  expect(update(    -3, 10, list  )).toEqual([ 10, 2, 3 ])})