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import {update} from './update'
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])})