Add LessonDetailScreen tests

Author: Mouad

iPhotoSchool.xcodeproj/project.pbxproj

@@ -53,6 +53,8 @@
 		EDB4DAC22976A20100F48EE7 /* RemoteDataSource.swift in Sources */ = {isa = PBXBuildFile; fileRef = EDB4DAC02976A20100F48EE7 /* RemoteDataSource.swift */; };
 		EDB4DAC52976A28300F48EE7 /* Constants.swift in Sources */ = {isa = PBXBuildFile; fileRef = EDB4DAC42976A28300F48EE7 /* Constants.swift */; };
 		EDB4DAC72976A34000F48EE7 /* Authentication.swift in Sources */ = {isa = PBXBuildFile; fileRef = EDB4DAC62976A34000F48EE7 /* Authentication.swift */; };
+		EDD14E2A297D7C34000831EF /* Fake.swift in Sources */ = {isa = PBXBuildFile; fileRef = EDD14E29297D7C34000831EF /* Fake.swift */; };
+		EDD14E30297D82AE000831EF /* LessonDetailScreenTest.swift in Sources */ = {isa = PBXBuildFile; fileRef = EDD14E2F297D82AE000831EF /* LessonDetailScreenTest.swift */; };
 		EDE9FEEB297B336B00E497A9 /* LessonDetailViewModelTest.swift in Sources */ = {isa = PBXBuildFile; fileRef = EDE9FEEA297B336B00E497A9 /* LessonDetailViewModelTest.swift */; };
 		EDE9FEED297B33DB00E497A9 /* MockVideoRepository.swift in Sources */ = {isa = PBXBuildFile; fileRef = EDE9FEEC297B33DB00E497A9 /* MockVideoRepository.swift */; };
 		EDE9FEF8297C69AF00E497A9 /* LessonListScreenTest.swift in Sources */ = {isa = PBXBuildFile; fileRef = EDE9FEF7297C69AF00E497A9 /* LessonListScreenTest.swift */; };
@@ -119,6 +121,8 @@
 		EDB4DAC02976A20100F48EE7 /* RemoteDataSource.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = RemoteDataSource.swift; sourceTree = "<group>"; };
 		EDB4DAC42976A28300F48EE7 /* Constants.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Constants.swift; sourceTree = "<group>"; };
 		EDB4DAC62976A34000F48EE7 /* Authentication.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Authentication.swift; sourceTree = "<group>"; };
+		EDD14E29297D7C34000831EF /* Fake.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Fake.swift; sourceTree = "<group>"; };
+		EDD14E2F297D82AE000831EF /* LessonDetailScreenTest.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LessonDetailScreenTest.swift; sourceTree = "<group>"; };
 		EDE9FEEA297B336B00E497A9 /* LessonDetailViewModelTest.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LessonDetailViewModelTest.swift; sourceTree = "<group>"; };
 		EDE9FEEC297B33DB00E497A9 /* MockVideoRepository.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MockVideoRepository.swift; sourceTree = "<group>"; };
 		EDE9FEF7297C69AF00E497A9 /* LessonListScreenTest.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LessonListScreenTest.swift; sourceTree = "<group>"; };
@@ -314,6 +318,7 @@
 			children = (
 				ED63BB292976D8EF008351E4 /* lessons.json */,
 				ED63BB272976D8AB008351E4 /* Stub.swift */,
+				EDD14E29297D7C34000831EF /* Fake.swift */,
 			);
 			path = Stub;
 			sourceTree = "<group>";
@@ -446,6 +451,7 @@
 			isa = PBXGroup;
 			children = (
 				EDE9FEEA297B336B00E497A9 /* LessonDetailViewModelTest.swift */,
+				EDD14E2F297D82AE000831EF /* LessonDetailScreenTest.swift */,
 			);
 			path = LessonDetails;
 			sourceTree = "<group>";
@@ -592,6 +598,7 @@
 				ED77DD742979B19B00A3B242 /* RemoteVideoSource.swift in Sources */,
 				ED5C80692976FD64007CBF22 /* Composer.swift in Sources */,
 				ED5C808129781C22007CBF22 /* RemoteImageSource.swift in Sources */,
+				EDD14E2A297D7C34000831EF /* Fake.swift in Sources */,
 				EDB4DA8B29769E1C00F48EE7 /* iPhotoSchoolApp.swift in Sources */,
 				EDB4DAC52976A28300F48EE7 /* Constants.swift in Sources */,
 				ED77DD7C297AA55900A3B242 /* LessonDetailViewModel.swift in Sources */,
@@ -620,6 +627,7 @@
 				EDE9FEEB297B336B00E497A9 /* LessonDetailViewModelTest.swift in Sources */,
 				ED63BB252976D868008351E4 /* TestHelpers.swift in Sources */,
 				ED14604D2978511B00A061C1 /* MockRemoteDataSource.swift in Sources */,
+				EDD14E30297D82AE000831EF /* LessonDetailScreenTest.swift in Sources */,
 				EDE9FEFC297C6B4400E497A9 /* MockLessonRepository.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;

iPhotoSchool/Model/Composer.swift

@@ -5,7 +5,13 @@
 //  Created by MOUAD BENJRINIJA on 17/1/2023.
 //
 
-import Foundation 
+import Foundation
+
+// For test purposes
+struct Env {
+  static let isRunningTests = ProcessInfo.processInfo.environment["isRunningTests"] != nil
+  static let useFake = ProcessInfo.processInfo.environment["useFake"] != nil
+}
 
 protocol Composing {
   @MainActor
@@ -15,8 +21,7 @@ protocol Composing {
 }
 
 class Composer: Composing {
-  static var shared: Composing = Composer()
-  private init() {}
+  static var shared: Composing = Env.useFake ? FakeComposer() : Composer()
 
   func appModel() -> AppModel {
     let lessonsRemoteDataSource = LessonsRemoteDataSourceMain(session: .default)

iPhotoSchool/Repositories/DataModels/Stub/Fake.swift

@@ -0,0 +1,32 @@
+//
+//  Fake.swift
+//  iPhotoSchool
+//
+//  Created by MOUAD BENJRINIJA on 22/1/2023.
+//
+
+import Foundation
+
+class FakeLessonsRepository: LessonsRepository {
+  func fetchLessons() async -> Loadable<[Lesson]> {
+    return .loaded(value: Stub.lessons)
+  }
+}
+
+class FakeComposer: Composing {
+
+  let realComposer = Composer()
+
+  func appModel() -> AppModel {
+    AppModel(lessonRepository: FakeLessonsRepository())
+  }
+
+  func imageRepository() -> ImageRepository {
+    realComposer.imageRepository()
+  }
+
+  func videoRepository() -> VideoRepository {
+    realComposer.videoRepository()
+  }
+
+}

iPhotoSchool/iPhotoSchoolApp.swift

@@ -9,12 +9,12 @@ import SwiftUI
 
 @main
 struct iPhotoSchoolApp: App {
+
   @StateObject var model = Composer.shared.appModel()
-  let isRunningTests = ProcessInfo.processInfo.environment["isRunningTests"] != nil
 
   var body: some Scene {
     WindowGroup {
-      if isRunningTests {
+      if Env.isRunningTests {
         // to avoid inaccurate coverage
         Text("IS TESTING")
       } else {
@@ -23,3 +23,4 @@ struct iPhotoSchoolApp: App {
     }
   }
 }
+

iPhotoSchoolTests/Mock/MockLessonRepository.swift

@@ -13,7 +13,6 @@ class MockLessonsRepository: LessonsRepository {
   var response: Loadable<[Lesson]> = .notLoaded
 
   func fetchLessons() async -> Loadable<[Lesson]> {
-    print("loaded", response.value?.count)
     return response
   }
 }

iPhotoSchoolTests/UI/LessonDetails/LessonDetailScreenTest.swift

@@ -0,0 +1,124 @@
+//
+//  LessonDetailScreenTest.swift
+//  iPhotoSchoolTests
+//
+//  Created by MOUAD BENJRINIJA on 22/1/2023.
+//
+
+import Foundation
+
+import XCTest
+import ViewInspector
+import SwiftUI
+import Combine
+import AVKit
+
+@testable import iPhotoSchool
+
+final class LessonDetailScreenTest: XCTestCase {
+  let lessons = Stub.lessons
+  var view: LessonDetailScreen!
+  var sut: LessonDetailViewController!
+  var viewModel: LessonDetailViewModel!
+
+  override func setUpWithError() throws {
+    view = LessonDetailScreen(lesson: lessons[0], onNext: {})
+    ViewHosting.host(view: view)
+    sut = try view.inspect().view(LessonDetailScreen.self).actualView().viewController()
+    viewModel = sut.viewModel
+  }
+
+  func test_LessonDetails_DisplayedCorrectly() throws {
+    // Given: a lesson
+    let lesson = lessons[1]
+    // When: we pass it to the viewModel
+    viewModel.lesson = lesson
+    // Then: views should be correctly updated
+    XCTAssertEqual(sut.nameLabel.text, lesson.name!)
+    XCTAssertEqual(sut.descriptionLabel.text, lesson.description!)
+    let videoURL = (sut.playerViewController.player?.currentItem?.asset as? AVURLAsset)?.url
+    XCTAssertEqual(videoURL, URL(string: lesson.videoURL!))
+  }
+
+  func test_NextButton_HiddenState() throws {
+    // Given: any lesson passed
+    viewModel.lesson = lessons[0]
+    // When: we pass a nil onNext closure
+    viewModel.onNext = nil
+    // Then: next button should be hidden
+    XCTAssertTrue(sut.nextButton.isHidden)
+    // When: we pass a valid onNext closure
+    viewModel.onNext = { }
+    // Then: next button should be displayed
+    XCTAssertFalse(sut.nextButton.isHidden)
+  }
+
+  func test_DownloadButton_State() throws {
+    // Given: any lesson passed
+    viewModel.lesson = lessons[0]
+
+    // When: the video is not downloaded
+    viewModel.downloadState = .normal
+    // Then: nav bar button should show a download button
+    XCTAssertFalse(sut.downloadButton.downloadButton.isHidden)
+
+    // When: the video is downloading
+    viewModel.downloadState = .downloading(progress: 25)
+    // Then: nav bar button should show the download progress
+    XCTAssertFalse(sut.downloadButton.downloadingButton.isHidden)
+    XCTAssertEqual(sut.downloadButton.downloadingButton.currentProgress, 0.25)
+
+    // When: the video is not downloaded
+    viewModel.downloadState = .downloaded
+    // Then: nav bar button should show a download button
+    XCTAssertFalse(sut.downloadButton.downloadedButton.isHidden)
+  }
+
+  func test_Player_StartPlaying() throws {
+    // Given: any lesson passed
+    viewModel.lesson = lessons[0]
+
+    // When: we view is loaded
+    // Then: start button should be displayed
+    XCTAssertFalse(sut.startButton.isHidden)
+    XCTAssertEqual(viewModel.playerState, .ready)
+
+    // When: we click on the start button
+    sut.startButton.sendActions(for: .touchUpInside)
+    // Then: next button should be hidden and player state updated
+    XCTAssertTrue(sut.startButton.isHidden)
+    XCTAssertEqual(viewModel.playerState, .playing)
+  }
+
+}
+
+struct LessonDetailScreenInspector {
+  let inspector: InspectableView<ViewType.ClassifiedView>
+
+  var loadable: InspectableView<ViewType.View<LoadableView<[Lesson], some View>>> {
+    get throws {
+      try inspector
+        .navigationStack()
+        .find(LoadableView<[Lesson], AnyView>.self)
+    }
+  }
+
+  var list: InspectableView<ViewType.List> {
+    get throws {
+      try loadable
+        .list(0)
+    }
+  }
+
+  var listItems: [InspectableView<ViewType.View<NavigationLink<LessonItemView, Never>>>] {
+    get throws {
+      try list.findAll(NavigationLink<LessonItemView, Never>.self)
+    }
+  }
+
+  var retryButton: InspectableView<ViewType.Button>  {
+    get throws {
+      try inspector.find(button: "Retry")
+    }
+  }
+}

iPhotoSchoolTests/UI/LessonDetails/LessonDetailViewModelTest.swift

@@ -21,6 +21,10 @@ final class TestLessonDetailViewModel: XCTestCase {
     sut = LessonDetailViewModel(videoRepository: videoRepository)
   }
 
+  override func tearDownWithError() throws {
+    videoRepository = nil
+  }
+
   func test_initialPreLoadingState() throws {
     // Given: No setup
     // Then
@@ -123,7 +127,7 @@ final class TestLessonDetailViewModel: XCTestCase {
       }
     }.store(in: &bag)
 
-    wait(for: [downloadingExpectation, downloadedExpectation], timeout: 1.0)
+    wait(for: [downloadingExpectation, downloadedExpectation], timeout: 5)
     // Then: repository should receive download request
     videoRepository.verify()
   }

iPhotoSchoolTests/UI/LessonsList/LessonListScreenTest.swift

@@ -13,15 +13,19 @@ import Combine
 
 final class LessonListScreenTest: XCTestCase {
   let lessons = Stub.lessons
-  let repository = MockLessonsRepository()
+  var repository: MockLessonsRepository!
   var view: LessonListScreen!
   var sut: LessonListScreenInspector!
 
   @MainActor
   override func setUpWithError() throws {
+    repository = MockLessonsRepository()
     view = LessonListScreen(model: AppModel(lessonRepository: repository))
     sut = LessonListScreenInspector(inspector: try view.inspect())
+  }
 
+  override func tearDownWithError() throws {
+    repository = nil
   }
 
   @MainActor
@@ -46,20 +50,20 @@ final class LessonListScreenTest: XCTestCase {
     // Given: a lesson loading failure response
     repository.response = .failed(error: APIError.unexpectedResponse)
     // When: view finish loading
-    let loadingExpectation = view.inspection.inspect(after: 0.3) { view in
-      let loadableView = try self.sut.loadable
+
+    let loadingExpectation = view.inspection.inspect(after: 5) { view in
       // Then: should display an error view with a retry button
       _ = try self.sut.retryButton
     }
     ViewHosting.host(view: view)
-    wait(for: [loadingExpectation], timeout: 1)
+    wait(for: [loadingExpectation], timeout: 6)
   }
 
   func test_LessonLoading_retryAfterFailure() throws {
     // Given: a lesson loading failure response
     repository.response = .failed(error: APIError.unexpectedResponse)
     let retryingExpectation = expectation(description: "Is retrying after failure")
-    let loadingExpectation = view.inspection.inspect(after: 0.3) { view in
+    let loadingExpectation = view.inspection.inspect(after: 5) { view in
       // When: we tap on retry while simulating a successful response
       self.repository.response = .loaded(value: self.lessons)
       let retryButton = try self.sut.retryButton
@@ -71,7 +75,7 @@ final class LessonListScreenTest: XCTestCase {
       }
     }
     ViewHosting.host(view: view)
-    wait(for: [loadingExpectation, retryingExpectation], timeout: 1)
+    wait(for: [loadingExpectation, retryingExpectation], timeout: 6)
   }
 
 }