steipete

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.

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1. Migration & Tooling Baseline

TALlama

class Anonymizer
  include ActiveSupport::Benchmarkable

  attr_reader :factory_names, :callbacks

  def initialize(factory_names = nil, callbacks = {})
    raise ArgumentError.new("You must be in development to use the anonymizer") unless Rails.env.development?
    require Rails.root.join("spec/factories") unless FactoryBot.factories.count > 0

    @factory_names = [*factory_names].compact.map(&:to_sym)

chockenberry

//
//  ContentView.swift
//  ObservableTester
//
//  Created by Craig Hockenberry on 4/18/24.
//

import SwiftUI

class BackingStore {

mattmassicotte

import SwiftUI
import AsyncAlgorithms

struct AsyncChanges<V>: ViewModifier where V : Equatable, V: Sendable {
    typealias Element = (oldValue: V, newValue: V)
    typealias Action = (AsyncStream<Element>) async -> Void

    @State private var streamPair = AsyncStream<Element>.makeStream()
    private let action: Action
    private let value: V

insidegui

# Add to your zsh profile

function devicepid() {
    if [ -z "$1" ]; then
        echo "Usage: devicepid <device-name> <search>"
        echo "Example: devicepid 'iPhone 15 Pro Max' SpringBoard"
        return 1
    fi
    
    if [ -z "$2" ]; then

ole

import SwiftUI

extension View {
    /// Proposes a percentage of its received proposed size to `self`.
    ///
    /// This modifier multiplies the proposed size it receives from its parent
    /// with the given factors for width and height.
    ///
    /// If the parent proposes `nil` or `.infinity` to us in any dimension,
    /// we’ll forward these values to our child view unchanged.

justin

#!/usr/bin/env zsh
#
# Convenience wrapper around the simctl command to perform operations related to iOS simulators.
# Author: Justin Williams (@justin)
#
# Usage: sim <options> <subcommand>
#
# This script is designed to work with ZSH. ymmv with other shells.

set -e

UnderscoreDavidSmith

@available(iOS 15.0, *)
struct TwinkleView:View {
    
    private func position(in proxy: GeometryProxy, sparkle:Sparkle) -> CGPoint {
        let radius = min(proxy.size.width, proxy.size.height) / 2.0
        let drawnRadius = (radius - 5) * sparkle.position.x
        let angle = Double.pi * 2.0 * sparkle.position.y

        let x = proxy.size.width * 0.5 + drawnRadius * cos(angle)
        let y = proxy.size.height * 0.5 + drawnRadius * sin(angle)

samsonjs

import Combine
import Foundation

public protocol BetterNotification {}

private extension BetterNotification {
    static var notificationName: Notification.Name {
        Notification.Name(rawValue: "BetterNotification:\(Self.self)")
    }
}

dejager

//
//  RoundedPolygon.swift
//
//  Created by Nate on 2022-10-17.
//

import SwiftUI

struct RoundedPolygon: Shape {