basic generator function

generator function

  it('generator function works', () => {
    function* anotherGenerator(i) {
      yield i + 1
      yield i + 2
      yield i + 3
    }

    function* generator(i){
      yield i
      yield* anotherGenerator(i)
      yield i + 10
    }

    const gen = generator(10)

    expect(gen.next()).to.eql({value: 10, done: false})
    expect(gen.next().value).to.eq(11)
    expect(gen.next().value).to.eq(12)
    expect(gen.next().value).to.eq(13)
    expect(gen.next().value).to.eq(20)
    expect(gen.next()).to.eql({value: undefined, done: true})
  })