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import { forEach } from './forEach.js'import { type } from './type.js'
test('happy', () => {  const sideEffect = {}  forEach(x => sideEffect[ `foo${ x }` ] = x + 10)([ 1, 2 ])
  expect(sideEffect).toEqual({    foo1 : 11,    foo2 : 12,  })})
test('iterate over object', () => {  const obj = {    a : 1,    b : [ 1, 2 ],    c : { d : 7 },    f : 'foo',  }  const result = {}  const returned = forEach((    val, prop, inputObj  ) => {    expect(type(inputObj)).toBe('Object')    result[ prop ] = `${ prop }-${ type(val) }`  })(obj)
  const expected = {    a : 'a-Number',    b : 'b-Array',    c : 'c-Object',    f : 'f-String',  }
  expect(result).toEqual(expected)  expect(returned).toEqual(obj)})
test('with empty list', () => {  const list = []  const result = forEach(x => x * x)(list)
  expect(result).toEqual(list)})
test('with wrong input', () => {  const list = undefined  const result = forEach(x => x * x)(list)
  expect(result).toBeUndefined()})
test('returns the input', () => {  const list = [ 1, 2, 3 ]  const result = forEach(x => x * x)(list)
  expect(result).toEqual(list)})