Async Unit Testing in Swift
Write robust and maintainable software using modern language features
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Unit testing will inherently nudge you toward writing your code in a maintainable way. You’ll separate concerns, design sensible interfaces, and break your code into small, easy-to-reason-about chunks.
Modern language features like async/await and functional reactive programming bring incredible ergonomics to our code. However, writing tests for code that executes asynchronously is not always straightforward.
I’ve always wanted to write this piece since I rarely see it explained well — frankly, it’s a tough set of concepts, and clearly, I think a lot of myself if I’m writing 12,000 words on the topic.
Introduction
It’s difficult to talk about testing without laying down some core concepts to get started. I would love to jump straight into advanced topics such as unstructured Tasks and Combine interoperation, but I’d rather start slow and ensure we’re all up to the same level of understanding as we go along.
