RxLua/tests/observer.lua

describe('Observer', function()
  describe('create', function()
    it('returns an Observer', function()
      expect(Rx.Observer.create()).to.be.an(Rx.Observer)
    end)

    it('assigns onNext, onError, and onCompleted', function()
      local function onNext() end
      local function onError() end
      local function onCompleted() end

      local observer = Rx.Observer.create(onNext, onError, onCompleted)

      expect(observer._onNext).to.equal(onNext)
      expect(observer._onError).to.equal(onError)
      expect(observer._onCompleted).to.equal(onCompleted)
    end)

    it('initializes stopped to false', function()
      expect(Rx.Observer.create().stopped).to.equal(false)
    end)
  end)

  describe('onNext', function()
    it('calls _onNext', function()
      local observer = Rx.Observer.create()
      local function run() observer:onNext() end
      expect(#spy(observer, '_onNext', run)).to.equal(1)
    end)

    it('passes all arguments to _onNext', function()
      local observer = Rx.Observer.create()
      local function run() observer:onNext(1, '2', 3, nil, 5) end
      expect(spy(observer, '_onNext', run)).to.equal({{1, '2', 3, nil, 5}})
    end)

    it('does not call _onNext if stopped is true', function()
      local observer = Rx.Observer.create()
      observer.stopped = true
      local function run() observer:onNext() end
      expect(#spy(observer, '_onNext', run)).to.equal(0)
    end)
  end)

  describe('onError', function()
    it('calls _onError with the first argument it was passed', function()
      local observer = Rx.Observer.create(_, function() end, _)
      local function run() observer:onError('sheeit', 1) end
      expect(spy(observer, '_onError', run)).to.equal({{'sheeit'}})
    end)

    it('sets stopped to true', function()
      local observer = Rx.Observer.create(_, function() end, _)
      observer:onError()
      expect(observer.stopped).to.equal(true)
    end)

    it('does not call _onError if stopped is already true', function()
      local observer = Rx.Observer.create(_, function() end, _)
      observer.stopped = true
      local function run() observer:onError() end
      expect(#spy(observer, '_onError', run)).to.equal(0)
    end)

    it('causes an error by default', function()
      local observer = Rx.Observer.create()
      expect(observer.onError).to.fail()
    end)
  end)

  describe('onCompleted', function()
    it('calls _onCompleted with no arguments', function()
      local observer = Rx.Observer.create()
      local function run() observer:onCompleted(1, 2, 3) end
      expect(spy(observer, '_onCompleted', run)).to.equal({{}})
    end)

    it('sets stopped to true', function()
      local observer = Rx.Observer.create()
      observer:onCompleted()
      expect(observer.stopped).to.equal(true)
    end)

    it('does not call _onCompleted if stopped is already true', function()
      local observer = Rx.Observer.create()
      observer.stopped = true
      local function run() observer:onCompleted() end
      expect(#spy(observer, '_onCompleted', run)).to.equal(0)
    end)
  end)
end)