Xcode essentials

10:26 - Warning and error annotations

#warning("This is a warning annotation")
#error("This is an error annotation")

10:58 - Mark comments

// MARK: This is a section title

14:09 - Placeholder

<#placeholder#>

17:30 - showStarView()

showStarView()

17:51 - Breakpoint #1

let task = URLSession.shared.dataTask(with: cloudURL, completionHandler: handleUpdatesFromCloud)

17:53 - Breakpoint #2

videos = loadVideosFromCloud()

18:17 - Swift error breakpoint

let url = try! getVideoResourceFilePath()

18:34 - Swift error throw

throw URLLoadError.fileNotFound

18:59 - Conditional breakpoint

cloudURL.scheme == "https"

19:18 - Print statement in conditional breakpoint

p "Username is \(cloudURL.user())"

19:44 - guard clause

guard cloudURLs.allSatisfy({ $0. scheme == "https" }),
    session.configuration.networkServiceType == .video else {
    return
}

19:56 - p session

p session

19:58 - p first part of guard clause

cloudURLs.allSatisfy({ $0. scheme == "https" })

20:02 - p second part of guard clause

p session.configuration.networkServiceType == .video

20:11 - Random star rating

var starRating: Int {
  let randomStarRating = Int.random(n: 1..<5)
  return randomStarRating
}

21:16 - Converting starRatingPercentage to Int

var starRating: Int {
  return Int((starRatingPercentage * 5).rounded())
}

21:46 - print statements for debugging

var releaseDate: Date {
    print("🎬 Entering func \(#function) in \(#fileID)...")
    let currentDate = Date()
    let gregorianCal = Calendar(identifier: .gregorian)
    var components = DateComponents()
    components.year = releaseYear
    print("\(#fileID)@\(#line) \(#function): 📅 releaseYear is \(releaseYear)")
    if releaseYear == gregorianCal.component(.year, from: currentDate) {
        components.month = Int(releaseMonth)
        isNewRelease = true
        print("\(#fileID)@\(#line) \(#function): 🆕 this is a new release!")
    }
    if releaseYear < 2000 {
        isClassicMovie = true
        print("\(#fileID)@\(#line) \(#function): 🎻 this one is a classic!")
    }
    let calendar = Calendar(identifier: .gregorian)
    return calendar.date(from: components)!
}

22:09 - os_log statements for debugging

var releaseDate: Date {
    os_log(.debug, "🎬 Entering func \(#function) in \(#file)...")
    let currentDate = Date()
    let gregorianCal = Calendar(identifier: .gregorian)
    var components = DateComponents()
    components.year = releaseYear
    os_log(.info, "📅 releaseYear is \(releaseYear)")
    if releaseYear == gregorianCal.component(.year, from: currentDate) {
        components.month = Int(releaseMonth)
        isNewRelease = true
        os_log(.info, "🆕 this is a new release!")
    }
    if releaseYear < 2000 {
        isClassicMovie = true
        os_log(.info, "🎻 this one is a classic!")
    }
    let calendar = Calendar(identifier: .gregorian)
    return calendar.date(from: components)!
}

23:19 - Sample unit tests

import Testing
@testable import Destination_Video

struct DestinationVideo_UnitTests {
    
    private var library = VideoLibrary()

    // Make sure starRating is returning a percentage
    @Test func testStarRating() async throws {
        for video in library.videos {
            #expect(video.info.starRating > 0)
            #expect(video.info.starRating <= 5)
        }
    }
    
    // Make sure the library loads data from the json file
    @Test func testLibraryLoaded() async throws {
        #expect(library.videos.count > 1)
    }

}

24:15 - Sample UI tests

import XCTest

final class Destination_VideoUITests: XCTestCase {
    
    private var app: XCUIApplication!

    @MainActor override func setUpWithError() throws {
        // UI tests must launch the application that they test.
        app = XCUIApplication()
        app.launch()
        
        // In UI tests it is usually best to stop immediately when a failure occurs.
        continueAfterFailure = false
    }

    @MainActor func testABeach() throws {
        // Tap the button to load the detail view for the "A Beach" video
        let aBeachButton = app.buttons["A Beach"].firstMatch
        aBeachButton.tap()
        
        // Make sure it has a Play Video button after going to that view
        let playButton = app.buttons["Play Video"]
        XCTAssert(playButton.exists)
        
        // Make sure the star rating for this video contains 4 stars to avoid issue we saw previously where it was only a single star because starRating was incorrectly a percentage instead of an Int
        let theRatingView = app.staticTexts["TheRating"]
        XCTAssert(theRatingView.label.contains("⭐️⭐️⭐️⭐️⭐️"))
    }
    
    @MainActor func testMainView() throws {
        // We should have at least 10 buttons for the various videos
        let buttons = app.buttons
        XCTAssert(buttons.count >= 10)
        
        // Check that the most popular videos have buttons for them
        for expectedVideo in ["By the Lake", "Camping in the Woods", "Ocean Breeze"] {
            XCTAssert(app.buttons[expectedVideo].exists)
        }
    }

    @MainActor func testLaunchPerformance() throws {
        if #available(macOS 10.15, iOS 13.0, tvOS 13.0, watchOS 7.0, *) {
            // This measures how long it takes to launch your application.
            measure(metrics: [XCTApplicationLaunchMetric()]) {
                XCUIApplication().launch()
            }
        }
    }
}

24:19 - Swift Testing tags

@Test(.tags(.stars)) func testStarRating() async throws {
    for video in library.videos {
        #expect(video.info.starRating > 0)
        #expect(video.info.starRating <= 5)
    }
}

@Test(.tags(.library)) func testLibraryLoaded() async throws {
  #expect(library.videos.count > 1)
}

extension Tag {
  @Tag static var stars: Tag
  @Tag static var library: Tag
}

26:35 - Running xcodebuild test from the command line

xcodebuild test -scheme DestinationVideo
xcodebuild test -scheme DestinationVideo -testPlan TestAllTheThings
xcodebuild test -scheme DestinationVideo -testPlan TestAllTheThings -only-testing "Destination VideoUITests/testABeach"

29:03 - Missing Code Coverage

func toggleUpNextState(for video: Video) {
    if !upNext.contains(video) {
        // Insert the video at the beginning of the list.
        upNext.insert(video, at: 0)
    } else {
        // Remove the entry with the matching identifier.
        upNext.removeAll(where: { $0.id == video.id })
    }
    // Persist the Up Next state to disk.
    saveUpNext()
}

29:19 - Code Coverage executed 5 times

init() {
    // Load all videos available in the library.
    videos = loadVideos()
    // The first time the app launches, set the last three videos as the default Up Next items.
    upNext = loadUpNextVideos(default: Array(videos.suffix(3)))
}