Halo, Habr! Saya mempersembahkan kepada Anda terjemahan artikel "Menguji Kode RxSwift Anda" oleh Shai Mishali dari raywenderlich.com .

Menulis aplikasi reaktif dengan RxSwift secara konseptual berbeda dari menulis aplikasi dengan cara "biasa". Ini berbeda dalam arti bahwa objek dalam aplikasi Anda biasanya tidak memiliki makna yang jelas, sebaliknya mereka akan diwakili oleh aliran nilai pada sumbu waktu, yang dikenal sebagai RxSwift Observable. Artikel ini akan memberi Anda kunci untuk menguji kode RxSwift.

Observable- Mekanisme kuat yang memungkinkan Anda, sebagai pengembang, untuk merespons perubahan dan memastikan bahwa keadaan aplikasi Anda selalu terkini. Bersama dengan semua manfaat yang diberikan ini, pengujian Observablebukanlah tugas sepele seperti hanya menggunakan XCTAssert untuk nilai-nilai biasa. Tapi jangan khawatir - artikel ini akan memandu Anda menjadi ahli dalam menguji RxSwift!

Artikel ini akan mengajarkan Anda cara membuat unit test untuk Observableutas. Anda akan mempelajari beberapa teknik yang tersedia untuk menguji kode RxSwift, serta beberapa tips. Ayo mulai.

Catatan: Artikel ini mengasumsikan bahwa Anda sudah terbiasa dengan RxSwift dan cara menulis tes sederhana menggunakan XCTest.

Mulai

Aplikasi reaktif berfungsi dengan baik ketika Anda perlu bekerja dengan mengubah konten, jadi kami akan bekerja dengan aplikasi seperti itu.

Unduh proyek pemula . Anda akan menemukan proyek awal untuk tutorial ini: Raytronome adalah aplikasi metronom yang dapat Anda gunakan untuk berlatih musik. Seperti yang dapat Anda pahami, karena fakta bahwa metronom bekerja seiring waktu, Anda harus melihat banyak logika yang dapat diuji.

Raytronome.xcworkspace. Main.storyboard. , .

. Play . (Signature) (Tempo).

UIViewController — MetronomeViewController.swift, MetronomeViewModel.swift -, .

Observable

RxSwift Observable .

, .

; . Observable , , () .

, :

,
. ""

, . , MetronomeViewModel, ViewModel - .

MetronomeViewModel.swift. ViewModel , : , ( ), , , , ,

UI. :

4
4/4
120
Play/Pause isPlaying
, , .
"" .
.even .odd —

RxSwift, RxBlocking RxTest. .

RxBlocking

RaytronomeTests.swift.

; RxSwift, RxCocoa, RxTest RxBlocking, viewModel setUp() MetronomeViewModel

, 4. , , . RxBlocking!

RxBlocking — RxSwift, : Observable BlockingObservable, Observable , .

, — , completed error —

RxBlocking , :

toArray(): .
first(): .
last(): .

, first().

RaytronomeTests:

func testNumeratorStartsAt4() throws {
  XCTAssertEqual(try viewModel.numeratorText.toBlocking().first(), "4")
  XCTAssertEqual(try viewModel.numeratorValue.toBlocking().first(), 4)
}

func testDenominatorStartsAt4() throws {
  XCTAssertEqual(try viewModel.denominatorText.toBlocking().first(), "4")
}

toBlocking() BlockingObservable, first() . XCTAssert .

, throws, RxBlocking . throws try! .

Command-U

signatureText 4/4, tempoText 120 BPM.

func testSignatureStartsAt4By4() throws {
  XCTAssertEqual(try viewModel.signatureText.toBlocking().first(), "4/4")
}

func testTempoStartsAt120() throws {
  XCTAssertEqual(try viewModel.tempoText.toBlocking().first(), "120 BPM")
}

RxBlocking

, RxBlocking , "" . , :

, , , , RxBlocking . , — — RxBlocking
RxBlocking . Observable , BlockingObservable .
, , RxBlocking , .
RxBlocking , .

. : Play/Pause isPlaying, (tappedPlayPause ). .

RxTest

, RxBlocking , , , .

RxTest!

RxTest RxBlocking, , , . - , — TestScheduler.

— RxSwift, , ,

RxSwift , .

: " ?"

RxTest — TestScheduler — . , Observable Observer, "" .

— .

TestScheduler. DisposeBag Disposable . viewModel :

var scheduler: TestScheduler!
var disposeBag: DisposeBag!

, setUp(), TestScheduler DisposeBag :

scheduler = TestScheduler(initialClock: 0)
disposeBag = DisposeBag()

TestScheduler initialClock, " " . DisposeBag . .

"" Play/Pause , isPlaying .

Observable "" tappedPlayPause.
Observer' isPlaying.
.

, !

. RxTest-:

func testTappedPlayPauseChangesIsPlaying() {
  // 1
  let isPlaying = scheduler.createObserver(Bool.self)

  // 2
  viewModel.isPlaying
    .drive(isPlaying)
    .disposed(by: disposeBag)

  // 3
  scheduler.createColdObservable([.next(10, ()),
                                  .next(20, ()),
                                  .next(30, ())])
           .bind(to: viewModel.tappedPlayPause)
           .disposed(by: disposeBag)

  // 4
  scheduler.start()

  // 5
  XCTAssertEqual(isPlaying.events, [
    .next(0, false),
    .next(10, true),
    .next(20, false),
    .next(30, true)
  ])
}

, . :

TestScheduler TestableObserver , Observable — Bool. Observaer — events, .
drive() "" viewModel.isPlaying TestableObserver. "" .
Observable, "" tappedPlayPause. , Observable, TestableObservable, TestScheduler "" .
start() .
XCTAssertEqual RxTest, , isPlaying , . 10, 20 30 , , 0 — isPlaying.

? : viewModel . , .

Command-u. 5 .

, 0, 10, 20 30 , .

RxTest (Date) , VirtualTimeUnit ( Int).

RxSwift — TestScheduler .

, — , , , 10 10 , . .

, TestScheduler, ?

func testModifyingNumeratorUpdatesNumeratorText() {
  let numerator = scheduler.createObserver(String.self)

  viewModel.numeratorText
           .drive(numerator)
           .disposed(by: disposeBag)

  scheduler.createColdObservable([.next(10, 3),
                                  .next(15, 1)])
           .bind(to: viewModel.steppedNumerator)
           .disposed(by: disposeBag)

  scheduler.start()

  XCTAssertEqual(numerator.events, [
    .next(0, "4"),
    .next(10, "3"),
    .next(15, "1")
  ])
}

func testModifyingDenominatorUpdatesNumeratorText() {
  let denominator = scheduler.createObserver(String.self)

  viewModel.denominatorText
           .drive(denominator)
           .disposed(by: disposeBag)

  // Denominator () -  2   `steppedDenominator + 1`.
  // f(1, 2, 3, 4) = 4, 8, 16, 32
  scheduler.createColdObservable([.next(10, 2),
                                  .next(15, 4),
                                  .next(20, 3),
                                  .next(25, 1)])
          .bind(to: viewModel.steppedDenominator)
          .disposed(by: disposeBag)

  scheduler.start()

  XCTAssertEqual(denominator.events, [
    .next(0, "4"),
    .next(10, "8"),
    .next(15, "32"),
    .next(20, "16"),
    .next(25, "4")
  ])
}

func testModifyingTempoUpdatesTempoText() {
  let tempo = scheduler.createObserver(String.self)

  viewModel.tempoText
           .drive(tempo)
           .disposed(by: disposeBag)

  scheduler.createColdObservable([.next(10, 75),
                                  .next(15, 90),
                                  .next(20, 180),
                                  .next(25, 60)])
           .bind(to: viewModel.tempo)
           .disposed(by: disposeBag)

  scheduler.start()

  XCTAssertEqual(tempo.events, [
    .next(0, "120 BPM"),
    .next(10, "75 BPM"),
    .next(15, "90 BPM"),
    .next(20, "180 BPM"),
    .next(25, "60 BPM")
  ])
}

testModifyingNumeratorUpdatesNumeratorText: , .
testModifyingDenominatorUpdatesNumeratorText: , .
testModifyingTempoUpdatesTempoText: ,

, , . , 3, 1. , numeratorText "4" ( ), "3", , , "1".

, denominatorText

, BPM

Command-U, 8 . !

, !

. :

func testModifyingSignatureUpdatesSignatureText() {
  // 1
  let signature = scheduler.createObserver(String.self)

  viewModel.signatureText
           .drive(signature)
           .disposed(by: disposeBag)

  // 2
  scheduler.createColdObservable([.next(5, 3),
                                  .next(10, 1),

                                  .next(20, 5),
                                  .next(25, 7),

                                  .next(35, 12),

                                  .next(45, 24),
                                  .next(50, 32)
                                ])
           .bind(to: viewModel.steppedNumerator)
           .disposed(by: disposeBag)

  // Denominator () -  2   `steppedDenominator + 1`.
  // f(1, 2, 3, 4) = 4, 8, 16, 32
  scheduler.createColdObservable([.next(15, 2), // switch to 8ths
                                  .next(30, 3), // switch to 16ths
                                  .next(40, 4)  // switch to 32nds
                                ])
           .bind(to: viewModel.steppedDenominator)
           .disposed(by: disposeBag)

  // 3
  scheduler.start()

  // 4
  XCTAssertEqual(signature.events, [
    .next(0, "4/4"),
    .next(5, "3/4"),
    .next(10, "1/4"),

    .next(15, "1/8"),
    .next(20, "5/8"),
    .next(25, "7/8"),

    .next(30, "7/16"),
    .next(35, "12/16"),

    .next(40, "12/32"),
    .next(45, "24/32"),
    .next(50, "32/32")
  ])
}

! , , . steppedNumerator steppedDenominator , signatureText .

. 9 !

, .

4/4
24/32.
"-" ; 16/16, 8/8, , , 4/4, 24/16, 24/8 24/4 — .

: , ,

func testModifyingDenominatorUpdatesNumeratorValueIfExceedsMaximum() {
  // 1
  let numerator = scheduler.createObserver(Double.self)

  viewModel.numeratorValue
           .drive(numerator)
           .disposed(by: disposeBag)

  // 2

  // Denominator () -  2   `steppedDenominator + 1`.
  // f(1, 2, 3, 4) = 4, 8, 16, 32
  scheduler.createColdObservable([
      .next(5, 4), // switch to 32nds
      .next(15, 3), // switch to 16ths
      .next(20, 2), // switch to 8ths
      .next(25, 1)  // switch to 4ths
      ])
      .bind(to: viewModel.steppedDenominator)
      .disposed(by: disposeBag)

  scheduler.createColdObservable([.next(10, 24)])
           .bind(to: viewModel.steppedNumerator)
           .disposed(by: disposeBag)

  // 3
  scheduler.start()

  // 4
  XCTAssertEqual(numerator.events, [
    .next(0, 4), //  4/4
    .next(10, 24), //  24/32
    .next(15, 16), //  16/16
    .next(20, 8), //  8/8
    .next(25, 4) //  4/4
  ])
}

, , ! :

, TestableObserver "" numeratorValue
, . 32, 24 ( ). 24/32. , numeratorValue.
schelduer
numeratorValue

! Command-U:

XCTAssertEqual failed: ("[next(4.0) @ 0, next(24.0) @ 10]") is not equal to ("[next(4.0) @ 0, next(24.0) @ 10, next(16.0) @ 15, next(8.0) @ 20, next(4.0) @ 25]") -

! .

, numeratorValue 24, , 24/16 24/4. :

, 4/8.
, 7/8.
. 4/4, 7/4 — !

, . :]

MetronomeViewModel.swift , numeratorValue:

numeratorValue = steppedNumerator
  .distinctUntilChanged()
  .asDriver(onErrorJustReturn: 0)

numeratorValue = steppedNumerator
  .distinctUntilChanged()
  .asDriver(onErrorJustReturn: 0)

steppedNumerator , steppedNumerator maxNumerator .

Command-U, 10 . !

viewModel. , 78%. !

: , Edit Scheme... - , , Tests, Options Code Coverage. Gather coverage for some targets Raytronome . Report Navigator

, . — .

, /, , ( )

— 32. RaytronomeTests.swift :

func testBeatBy32() {
  // 1
  viewModel = MetronomeViewModel(initialMeter: Meter(signature: "4/32"),
                                 autoplay: true,
                                 beatScheduler: scheduler)

  // 2
  let beat = scheduler.createObserver(Beat.self)
  viewModel.beat.asObservable()
    .take(8)
    .bind(to: beat)
    .disposed(by: disposeBag)

  // 3
  scheduler.start()

  XCTAssertEqual(beat.events, [])
}

. - :

viewModel . 4/32, , tappedPlayPause .
. , viewModel SerialDispatchQueueScheduler , TestScheduler, , .
TestableObserver Beat 8 beat. 8 — , , .
scheduler. , , , — .

Command-U. :

XCTAssertEqual failed: ("[next(first) @ 1, next(regular) @ 2, next(regular) @ 3, next(regular) @ 4, next(first) @ 5, next(regular) @ 6, next(regular) @ 7, next(regular) @ 8, completed @ 8]") is not equal to ("[]") —

, , ? 1 8.

, - , 4/32 4/4. , .

Meter(signature: "4/32") Meter(signature: "4/4") Command-U. - - .

, ! , - , . , ? -, VirtualTimeUnit, .

120 BPM, 4 ( 4/4), 0.5 . 32, 0.0625 .

, — , TestScheduler , VirtualTimeUnit.

resolution . resolution — TestScheduler 1.

0.0625/1 1, 0.5/1 1, .

, resolution, .

viewModel, , :

scheduler = TestScheduler(initialClock: 0, resolution: 0.01)

resolution

resoulution

4/32 viewModel Command-U.

, .

XCTAssertEqual failed: ("[next(first) @ 6, next(regular) @ 12, next(regular) @ 18, next(regular) @ 24, next(first) @ 30, next(regular) @ 36, next(regular) @ 42, next(regular) @ 48, completed @ 48]") is not equal to ("[]") —

6. XCTAssertEqual :

XCTAssertEqual(beat.events, [
  .next(6, .first),
  .next(12, .regular),
  .next(18, .regular),
  .next(24, .regular),
  .next(30, .first),
  .next(36, .regular),
  .next(42, .regular),
  .next(48, .regular),
  .completed(48)
])

Command-U, , . !

- 4/4 .

func testBeatBy4() {
  scheduler = TestScheduler(initialClock: 0, resolution: 0.1)

  viewModel = MetronomeViewModel(initialMeter: Meter(signature: "4/4"),
                                 autoplay: true,
                                 beatScheduler: scheduler)

  let beat = scheduler.createObserver(Beat.self)
  viewModel.beat.asObservable()
    .take(8)
    .bind(to: beat)
    .disposed(by: disposeBag)

  scheduler.start()

  XCTAssertEqual(beat.events, [
    .next(5, .first),
    .next(10, .regular),
    .next(15, .regular),
    .next(20, .regular),
    .next(25, .first),
    .next(30, .regular),
    .next(35, .regular),
    .next(40, .regular),
    .completed(40)
  ])
}

— , resolution, 0.1, 4.

Command-U, , 12 !

, , 99.25% MetronomeViewModel, . : beatType.

beatType — , , , beatType .even .odd. . , , :

func testBeatTypeAlternates() {
  scheduler = TestScheduler(initialClock: 0, resolution: 0.1)

  viewModel = MetronomeViewModel(initialMeter: Meter(signature: "4/4"),
                                 autoplay: true,
                                 beatScheduler: scheduler)

  let beatType = scheduler.createObserver(BeatType.self)
  viewModel.beatType.asObservable()
    .take(8)
    .bind(to: beatType)
    .disposed(by: disposeBag)

  scheduler.start()

  XCTAssertEqual(beatType.events, [
    .next(5, .even),
    .next(10, .odd),
    .next(15, .even),
    .next(20, .odd),
    .next(25, .even),
    .next(30, .odd),
    .next(35, .even),
    .next(40, .odd),
    .completed(40)
  ])
}

?

, . , RxSwift. RxBlocking , RxTest .

, Scheduler, TestScheduler .

Ada banyak lagi yang dapat dipelajari baik di RxSwift dan di RxBlocking - pekerjaan internal mereka, operator dan sebagainya. Tempat terbaik untuk melanjutkan adalah dokumentasi RxSwift resmi , serta daftar operator RxBlocking .

Jika Anda memiliki pertanyaan, atau komentar pada konten artikel - selamat datang di komentar, atau dalam diskusi artikel asli . Terima kasih sudah membaca! Peringatan , artikel ini adalah terjemahan dari artikel dari raywenderlich.com .

Tes unit untuk kode RxSwift

Mulai

Observable

RxBlocking

RxBlocking

RxTest

?

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