Jan Remeš janremes

The Ultimate Swift Testing Playbook (2024 WWDC Edition, expanded with Apple docs from June 2025)

Updated with info from https://developer.apple.com/documentation/testing fetched via Firecrawl on June 7, 2025.

See also my blog: See also my blog post: https://steipete.me/posts/2025/migrating-700-tests-to-swift-testing

A hands-on, comprehensive guide for migrating from XCTest to Swift Testing and mastering the new framework. This playbook integrates the latest patterns and best practices from WWDC 2024 and official Apple documentation to make your tests more powerful, expressive, and maintainable.

1. Migration & Tooling Baseline

Here's my own list of the interesting stuff announced during this year's WWDC, collected from the keynotes, various Apple docs, blog posts and tweets.

If you're planning to watch the videos, I really recommend this Mac app that helps you download and watch them: https://github.com/insidegui/WWDC.

OS X El Capitan

http://www.apple.com/osx/elcapitan-preview/

split view - two apps side by side on full screen

	//
	// PagingView.swift
	// Wallaroo - https://wallaroo.app
	//
	// Created by Sean Heber (@BigZaphod) on 8/9/22.
	//

	import SwiftUI

	// This exists because SwiftUI's paging setup is kind of broken and/or wrong out of the box right now.

	import ContactTracing

	extension CTExposureDetectionSession {
	func addPositiveDiagnosisKeys(batching keys: [CTDailyTracingKey], completion: CTErrorHandler) {
	if keys.isEmpty {
	completion(nil)
	} else {
	let cursor = keys.index(keys.startIndex, offsetBy: maxKeyCount, limitedBy: keys.endIndex) ?? keys.endIndex
	let batch = Array(keys.prefix(upTo: cursor))
	let remaining = Array(keys.suffix(from: cursor))

	import UIKit
	import Combine

	/*
	# References
	- [ra1028/SwiftUI-Combine: This is an example project of SwiftUI and Combine using GitHub API.](https://github.com/ra1028/SwiftUI-Combine)
	- [marty-suzuki/GitHubSearchWithSwiftUI: SwiftUI and Combine based GitHubSearch example.](https://github.com/marty-suzuki/GitHubSearchWithSwiftUI)
	- [DataTaskPublisherを作ってみた](https://gist.github.com/yamoridon/16c1cc70ac46e50def4ca6695ceff772)
	- [【iOS】Combineフレームワークまとめ(2019/6/9時点) - Qiita](https://qiita.com/shiz/items/5efac86479db77a52ccc)
	*/

	/**
	Writes a set of objects in the database.

	- parameter objects: Array of `Objects` to be stored on the database
	- parameter configuration: Realm `Configuration` in which the write action will be performed
	- parameter update: Enabled the custom update maintaining existing relationships
	*/
	static func write(objects : [Object], configuration: Realm.Configuration, update: Bool = false) {
	if let realm = try? Realm(configuration: configuration) {
	realm.beginWrite()

	#!/bin/sh
	# Create a RAM disk with same perms as mountpoint
	# Script based on http://itux.idev.pro/2012/04/iservice-speed-up-your-xcode-%D0%BD%D0%B5%D0%BA%D0%BE%D1%82%D0%BE%D1%80%D1%8B%D0%B5-%D1%81%D0%BF%D0%BE%D1%81%D0%BE%D0%B1%D1%8B/ with some additions
	# Usage: sudo ./xcode_ramdisk.sh start

	USERNAME=$(logname)

	TMP_DIR="/private/tmp"
	RUN_DIR="/var/run"

	/// Observes a run loop to detect any stalling or blocking that occurs.
	///
	/// This class is thread-safe.
	@interface GHRunLoopWatchdog : NSObject

	/// Initializes the receiver to watch the specified run loop, using a default
	/// stalling threshold.
	- (id)initWithRunLoop:(CFRunLoopRef)runLoop;

	/// Initializes the receiver to detect when the specified run loop blocks for

	//
	// AMScanViewController.h
	//
	//
	// Created by Alexander Mack on 11.10.13.
	// Copyright (c) 2013 ama-dev.com. All rights reserved.
	//

	#import <UIKit/UIKit.h>
	#import <AVFoundation/AVFoundation.h>