describe('amb', function()
  it('returns nil if it is passed nil', function()
    expect(Rx.Observable.amb()).to.equal(nil)
  end)

  it('returns the Observable unchanged if it is the only one supplied', function()
    expect(Rx.Observable.amb(Rx.Observable.fromRange(3))).to.produce(1, 2, 3)
  end)

  it('produces values from the first Observable to produce a value', function()
    local a = Rx.Subject.create()
    local b = Rx.Subject.create()
    local onNext = spy()
    local observer = Rx.Observer.create(onNext)
    local amb = a:amb(b):subscribe(observer)

    b:onNext(4)
    a:onNext(1)
    b:onNext(5)
    b:onNext(6)
    b:onCompleted()
    a:onNext(2)
    a:onNext(3)
    a:onCompleted()

    expect(onNext).to.equal({{4}, {5}, {6}})
  end)
end)