iOS Test Night #3: ViewController ⇄ State by RxSwift

https://testnight.connpass.com/event/49561/

Transcript

1. ViewController ⁶ Presenter
   by RxSwift
   iOS Test Night #3
   

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2. ࣗݾ঺հ
   • Takeshi Ihara / @nonchalant0303
   • Recruit Marketing Partners
   • iOS Engineer
   

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3. RxSwift
   Rx is a generic abstraction of computation
   expressed through Observable
   interface.
   This is a Swift version of Rx.
   

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4. ViewController ⁶ Presenter
   

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5. ViewController
   • ը໘දࣔ΍ϢʔβͷλονΠϕϯτͳͲͷ
   EventΛPresenterʹ௨஌͢Δ
   • Presenter͔Βड͚औͬͨStateʹΑΓView
   ͷදࣔΛ੾Γସ͑Δ
   

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6. Presenter
   • View͔ΒEventΛड͚औΓɺඞཁ͕͋Ε͹
   EventʹԠͨ͡UseCaseΛ࣮ߦ͢Δ
   • UseCase͔Βड͚औͬͨσʔλΛStateͱ͠
   ͯView΁౉͢
   

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7. ViewController (VC)
   Presenter
   State Event
   

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8. prepare
   VC
   viewWillAppear
   Presenter
   → Event
   State ←
   prepared
   "1*$BMM
   Refresh View
   touch
   touched
   %POPUIJOH
   Refresh View
   touchEvent
   

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9. class Presenter {
   enum State {
   case initial
   case prepared(value: Int)
   case touched
   }
   enum Event {
   case prepare
   case touch
   }
   let eventReciever = PublishSubject()
   private let innerViewRefrector = BehaviorSubject(value: .initial)
   private let disposeBag = DisposeBag()
   var viewRefrector: Observable {
   return innerViewRefrector.asObservable()
   }
   init() {
   eventReciever
   .flatMap { event -> Observable in
   switch event {
   case .prepare:
   return [API Call]
   .map {
   .prepared(value: $0)
   }
   case .touch:
   return Observable.just(.touched)
   }
   }
   .bindTo(innerViewRefrector)
   .addDisposableTo(disposeBag)
   }
   }
   

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10. class Presenter {
    enum State { // VCʹฦ͢ঢ়ଶ
    case initial
    case prepared(value: Int)
    case touched
    }
    enum Event { // VC͔Βड͚औΔΠϕϯτ
    case prepare
    case touch
    }
    

    …
    }
    

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11. class Presenter {
    …
    let eventReciever = PublishSubject()
    private let innerViewRefrector =
    BehaviorSubject(value: .initial)
    private let disposeBag = DisposeBag()
    var viewRefrector: Observable {
    return innerViewRefrector.asObservable()
    }
    …
    }
    ௨஌ɾड৴ܥͷαϒδΣΫτ
    

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12. class Presenter {
    …
    init() {
    eventReciever
    .flatMap { event -> Observable in
    switch event {
    case .prepare:
    return [API Call]
    .map {
    .prepared(value: $0)
    }
    case .touch:
    return Observable.just(.touched)
    }
    }
    .bindTo(innerViewRefrector)
    .addDisposableTo(disposeBag)
    }
    }
    

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13. class Presenter {
    enum State {
    case initial
    case prepared(value: Int)
    case touched
    }
    enum Event {
    case prepare
    case touch
    }
    let eventReciever = PublishSubject()
    private let innerViewRefrector = BehaviorSubject(value: .initial)
    private let disposeBag = DisposeBag()
    var viewRefrector: Observable {
    return innerViewRefrector.asObservable()
    }
    init() {
    eventReciever
    .flatMap { event -> Observable in
    switch event {
    case .prepare:
    return [API Call]
    .map {
    .prepared(value: $0)
    }
    case .touch:
    return Observable.just(.touched)
    }
    }
    .bindTo(innerViewRefrector)
    .addDisposableTo(disposeBag)
    }
    }
    VCʹฦ͢ঢ়ଶ
    VC͔Βड͚औΔΠϕϯτ
    ௨஌ɾड৴ܥͷαϒδΣΫτ
    ΠϕϯτΛड͚औͬͯ
    ঢ়ଶΛฦ͢
    

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14. class ViewController: UIViewController {
    typealias Event = Presenter.Event
    var presenter: Presenter!
    private let disposeBag = DisposeBag()
    override func viewDidLoad() {
    setupUIBindings()
    setupEventBindings()
    }
    private func setupUIBindings() {
    presenter.viewRefrector
    .asDriver(onErrorDriveWith: .empty())
    .drive(
    onNext: { state in
    switch state {
    case .initial:
    break
    case .prepared(let value):
    // API͔Βͷ݁ՌΛ༻͍ͯViewʹ൓ө͢Δ
    case .touched:
    // Touchͷ݁ՌΛViewʹ൓ө͢Δ
    }
    }
    )
    .addDisposableTo(disposeBag)
    }
    private func setupEventBindings() {
    rx.sentMessage(#selector(UIViewController.viewWillAppear(_:)))
    .map { _ in () }
    .shareReplay(1)
    .map {
    return Event.prepare
    }
    .bindTo(presenter.eventReciever)
    .addDisposableTo(disposeBag)
    btn.rx.tap
    .map {
    return Event.touch
    }
    .bindTo(presenter.eventReciever)
    .addDisposableTo(disposeBag)
    }
    }
    

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15. class ViewController: UIViewController {
    typealias Event = Presenter.Event
    var presenter: Presenter!
    private let disposeBag = DisposeBag()
    override func viewDidLoad() {
    setupUIBindings()
    setupEventBindings()
    }
    …
    }
    

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16. class ViewController: UIViewController {
    …
    private func setupUIBindings() {
    presenter.viewRefrector
    .asDriver(onErrorDriveWith: .empty())
    .drive(
    onNext: { state in
    switch state {
    case .initial:
    break
    case .prepared(let value):
    // API͔Βͷ݁ՌΛ༻͍ͯViewʹ൓ө͢Δ
    case .touched:
    // Touchͷ݁ՌΛViewʹ൓ө͢Δ
    }
    }
    )
    .addDisposableTo(disposeBag)
    }
    …
    }
    

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17. class ViewController: UIViewController {
    …
    private func setupEventBindings() {
    rx.sentMessage(#selector(UIViewController.viewWillAppear(_:)))
    // viewWillAppearΛPresenterʹྲྀͯ͠Δ
    .map { _ in () }
    .shareReplay(1)
    .map {
    return Event.prepare
    }
    .bindTo(presenter.eventReciever)
    .addDisposableTo(disposeBag)
    btn.rx.tap // ϘλϯͷλονΠϕϯτΛPresenterʹྲྀͯ͠Δ
    .map {
    return Event.touch
    }
    .bindTo(presenter.eventReciever)
    .addDisposableTo(disposeBag)
    }
    }
    

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18. class ViewController: UIViewController {
    typealias Event = Presenter.Event
    var presenter: Presenter!
    private let disposeBag = DisposeBag()
    override func viewDidLoad() {
    setupUIBindings()
    setupEventBindings()
    }
    private func setupUIBindings() {
    presenter.viewRefrector
    .asDriver(onErrorDriveWith: .empty())
    .drive(
    onNext: { state in
    switch state {
    case .initial:
    break
    case .prepared(let value):
    // API͔Βͷ݁ՌΛ༻͍ͯViewʹ൓ө͢Δ
    case .touched:
    // Touchͷ݁ՌΛViewʹ൓ө͢Δ
    }
    }
    )
    .addDisposableTo(disposeBag)
    }
    private func setupEventBindings() {
    rx.sentMessage(#selector(UIViewController.viewWillAppear(_:)))
    .map { _ in () }
    .shareReplay(1)
    .map {
    return Event.prepare
    }
    .bindTo(presenter.eventReciever)
    .addDisposableTo(disposeBag)
    btn.rx.tap
    .map {
    return Event.touch
    }
    .bindTo(presenter.eventReciever)
    .addDisposableTo(disposeBag)
    }
    }
    StateΛड͚औͬͯ
    ViewΛ൓ө͢Δ
    EventΛૹΔ
    

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19. prepare
    VC
    viewWillAppear
    Presenter
    → Event
    State ←
    prepared
    "1*$BMM
    Refresh View
    touch
    touched
    %POPUIJOH
    Refresh View
    touchEvent
    

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20. ViewController (VC)
    Presenter
    State Event
    

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21. Test
    

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22. ViewController (VC)
    Presenter
    State Event
    

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23. ViewController (VC)
    Presenter
    State Event
    Testର৅
    

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24. Test Case
    • Input: VC͔Βड͚औΔEvent
    • Output: Presenter͕VCʹૹΔState
    

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25. prepare
    VC
    viewWillAppear
    Presenter
    → Event
    State ←
    prepared
    "1*$BMM
    Refresh View
    touch
    touched
    %POPUIJOH
    Refresh View
    touchEvent
    

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26. %POPUIJOH
    "1*$BMM
    VC
    viewWillAppear
    Presenter
    → Event
    State ←
    prepare
    prepared
    Refresh View
    touch
    touched
    Refresh View
    touchEvent
    Test Case
    Test Case
    

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27. Test with Rx
    • Rx͸σʔλ͕࣍ݩͱ͍͏୯ҐΛ͍࣋ͬͯΔ
    ͷͰɺ࣌ࠁʹΑͬͯҧ͏ঢ়ଶΛ͍࣋ͬͯΔ
    • ࣌ࠁʹґଘ͢Δςετ͸؀ڥґଘ͕େ͖͘
    ෆ҆ఆͳςετʹͳΓ΍͍͢
    

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28. RxTest
    • RxSwiftͷςετ༻ϑϨʔϜϫʔΫ
    • ࣮࣌ؒͱ͸ҟͳΔԾ૝࣌ؒʹج͖ͮΠϕϯ
    τΛൃੜͤ͞Δ࢓૊Έ
    

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29. // 5FTUBCMF0CTFSWBCMF1SFTFOUFS4UBUFΛੜ੒
    let observer = scheduler.createObserver(Presenter.State.self)
    let xs = scheduler.createColdObservable([
    // Ծ૝࣌ࠁ100ޙʹprepareΠϕϯτΛૹΔ
    next(100, Presenter.UserEvent.prepare)
    ])
    // Ծ૝࣌ࠁ100ʹxsΛeventReceiverʹbinding͢Δ
    // ஗ԆධՁ͕૸Δ
    scheduler.scheduleAt(100) {
    xs
    .bindTo(presenter.eventReceiver)
    .addDisposableTo(disposeBag)
    }
    // WJFX3FGMFDUFSΛobserverʹSubscribeͤ͞Δ
    scheduler.scheduleAt(200) {
    presenter.viewReflecter
    .subscribe(observer)
    .addDisposableTo(disposeBag)
    }
    

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30. Test Case
    

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31. class PresenterSpec: QuickSpec {
    override func spec() {
    describe("Presenter") {
    var presenter: Presenter!
    var scheduler: TestScheduler!
    var disposeBag: DisposeBag!
    beforeEach {
    scheduler = TestScheduler(initialClock: 0)
    presenter = Presenter()
    disposeBag = DisposeBag()
    }
    context("when prepare") {
    it("prepared") {
    let observer = scheduler.createObserver(Presenter.State.self)
    let xs = scheduler.createColdObservable([
    next(100, Presenter.UserEvent.prepare)
    ])
    scheduler.scheduleAt(100) {
    xs
    .bindTo(presenter.eventReceiver)
    .addDisposableTo(disposeBag)
    }
    scheduler.scheduleAt(200) {
    presenter.viewReflecter
    .subscribe(observer)
    .addDisposableTo(disposeBag)
    }
    scheduler.start()
    expect(observer.events.count).to(equal(2))
    expect(observer.events[0].time).to(equal(200))
    expect(observer.events[1].time).to(equal(300))
    let initial = observer.events[0].value.element
    expect(initial).toNot(beNil())
    expect(initial!).to(equal(Presenter.State.initial))
    let subject = observer.events[1].value.element
    expect(subject).toNot(beNil())
    expect(subject!).to(equal(Presenter.State.prepared(value: 1)))
    }
    }
    }
    }
    }
    

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32. class PresenterSpec: QuickSpec {
    override func spec() {
    describe("Presenter") {
    var presenter: Presenter!
    var scheduler: TestScheduler!
    var disposeBag: DisposeBag!
    beforeEach {
    scheduler = TestScheduler(initialClock: 0)
    presenter = Presenter()
    disposeBag = DisposeBag()
    }
    …
    }
    }
    }
    

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33. class PresenterSpec: QuickSpec {
    override func spec() {
    describe("Presenter") {
    …
    context("when prepare") {
    it("prepared") {
    let observer = scheduler.createObserver(Presenter.State.self)
    let xs = scheduler.createColdObservable([
    next(100, Presenter.UserEvent.prepare)
    ])
    scheduler.scheduleAt(100) {
    xs
    .bindTo(presenter.eventReceiver)
    .addDisposableTo(disposeBag)
    }
    scheduler.scheduleAt(200) {
    presenter.viewReflecter
    .subscribe(observer)
    .addDisposableTo(disposeBag)
    }
    scheduler.start()
    …
    }
    }
    }
    }
    }
    

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34. class PresenterSpec: QuickSpec {
    override func spec() {
    describe("Presenter") {
    …
    context("when prepare") {
    it("prepared") {
    …
    expect(observer.events.count).to(equal(2))
    expect(observer.events[0].time).to(equal(200))
    expect(observer.events[1].time).to(equal(200))
    let initial = observer.events[0].value.element
    expect(initial).toNot(beNil())
    expect(initial!).to(equal(Presenter.State.initial))
    let subject = observer.events[1].value.element
    expect(subject).toNot(beNil())
    expect(subject!).to(equal(Presenter.State.prepared(value: 1)))
    }
    }
    }
    }
    }
    ड͚ͱͬͨঢ়ଶͷ
    ൃੜͨ࣌͠ࠁɾछྨΛݕূ
    

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35. class PresenterSpec: QuickSpec {
    override func spec() {
    describe("Presenter") {
    var presenter: Presenter!
    var scheduler: TestScheduler!
    var disposeBag: DisposeBag!
    beforeEach {
    scheduler = TestScheduler(initialClock: 0)
    presenter = Presenter()
    disposeBag = DisposeBag()
    }
    context("when prepare") {
    it("prepared") {
    let observer = scheduler.createObserver(Presenter.State.self)
    let xs = scheduler.createColdObservable([
    next(100, Presenter.UserEvent.prepare)
    ])
    scheduler.scheduleAt(100) {
    xs
    .bindTo(presenter.eventReceiver)
    .addDisposableTo(disposeBag)
    }
    scheduler.scheduleAt(200) {
    presenter.viewReflecter
    .subscribe(observer)
    .addDisposableTo(disposeBag)
    }
    scheduler.start()
    expect(observer.events.count).to(equal(2))
    expect(observer.events[0].time).to(equal(200))
    expect(observer.events[1].time).to(equal(200))
    let initial = observer.events[0].value.element
    expect(initial).toNot(beNil())
    expect(initial!).to(equal(Presenter.State.initial))
    let subject = observer.events[1].value.element
    expect(subject).toNot(beNil())
    expect(subject!).to(equal(Presenter.State.prepared(value: 1)))
    }
    }
    }
    }
    }
    ड͚ͱͬͨঢ়ଶͷ
    ൃੜͨ࣌͠ࠁɾछྨΛݕূ
    Ծ૝࣌ࠁ্Ͱͷ
    ΠϕϯτϋϯυϦϯάΛઃఆ
    

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36. ViewController (VC)
    Presenter
    State Event
    

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37. ·ͱΊ
    • ViewͷඳըͳͲʹґଘ͠ͳ͍γϯϓϧͳ

    ΠϕϯτϕʔεͷςετΛॻ͚ͨ
    • ·ͨɺෳ਺ͷΠϕϯτΛϋϯυϦϯά͢Δ
    ͜ͱͰෳࡶͳςετΛλΠϛϯάʹґଘ͞
    ͤΔ͜ͱͳ͘ॻ͘͜ͱ͕ग़དྷΔ
    

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