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import {reduce} from './reduce'
const reducer = (prev, current, i) => {  expect(i).toBeNumber()
  return prev + current}const initialValue = 1const list = [1, 2, 3]const ERROR = 'reduce: list must be array or iterable'
test('happy', () => {  expect(reduce(reducer, initialValue, list)).toEqual(7)})
test('with object as iterable', () => {  expect(() =>    reduce(reducer, initialValue, {      a: 1,      b: 2,    })  ).toThrowWithMessage(TypeError, ERROR)})
test('with undefined as iterable', () => {  expect(() => reduce(reducer, 0, null)).toThrowWithMessage(TypeError, ERROR)})