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Issue 56
Jul 01, 2025

WWDC announcement? Hello? Where are you? We miss you! 🥺

Festivals start to announce their line-ups, friends are planning holidays, and we engineers are starting to hope for in-person conferences later this year.

It's hard to tell whether this is actually going to happen, but there's one thing interesting: WWDC is still not announced.

Mischa had a perfect point: we don't need time to book flights and hotels as it's likely not in-person either way. It makes sense, but it also brings sadness! What if WWDC is delayed and happens in August? In-person? Is that even an option?

Either way, WWDC will happen this year, and whether or not it's in person, I really hope they'll deliver the same format of short videos, which allowed us all to watch way more sessions last year than at other WWDC editions.

Enjoy this week's SwiftLee Weekly!

THIS WEEK'S BLOG POST
You can test optionals in Swift in several ways, but they don't always end up in a readable unit test. I always try to write convenience methods to make this a little bit nicer, for which I'm sharing with you a few today.

TWEET OF THE WEEK
I really liked both this video with animation and the actual code implementation by Jérôme Alves. It’s showing how you can extend the Result enum and make it chainable handling failures in your code.

SPONSORED
ViRE is a Visual Regular Expressions tool: Readable Regex • Code Complete / Cheat Sheet • Unit Tests • Powerful Replace System • Step-by-Step Search & Replace • Regex Visual Scheme • Regex History / Playground. ViRE is available on Mac & iPad.

CURATED FROM THE COMMUNITY

CODE
Futures and Promises in Combine can be a great solution to performing asynchronous work. John Sundell explains how they work together with covering how you can use subjects to send values for specific events. I really liked his example of an image processor which sends specific processing progress events.
I enjoyed reading this article by Tom "Tom" Harrington, and I concluded (once again) two things out of it. Some APIs seriously leak documentation (ánd example code), and we are really ready for an update of the Core Data library. How about SwiftData? WWDC 2021, maybe? Let’s see!
An interesting Property Wrapper that comes by default within the SwiftUI framework. I wasn’t aware of this one, and Keith Harrison explains what you can do with it.
I really liked this post by Wattmaller, explaining how he created the Aurora background animation in his app Pearl. The post is detailed with videos, images and even covers accessibility.
SwiftOnTap aims to deliver complete SwiftUI Docs with examples! It’s currently based on a single SwiftUI.swift file, and you can help to add documentation too. The site works by searching for any struct, enum, function, or any other SwiftUI symbol and sometimes comes with even animating previews of code examples.

WORKFLOW
It’s not often that I find a blog post and realize it covers things that are ‘normal’ and ‘known’ to me, just because of experience. It made me realize that some things aren’t easy to understand when you’re new to app development. Understanding and managing the Xcode spaces like Derived data is one of them, and Keegan Rush got you covered.
An interesting article by Leo G Dion covers upgrading old apps. Backed by several podcasts that add to the story. If you’re about to migrate or refactor an old app, this post is for you.
I wasn’t aware this was possible on macOS, and I’ve always been using DevCleaner. However, this tip by Paris Xavier Pinkney seems pretty nice and is built-in by default on macOS!

ACCESSIBILITY
An interesting new approach to testing accessibility. Mobile A11Y explains how Evinced works and how it helps to test for accessibility. The tool is commonly used on the web and can add more valuable features in the future.

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