Both Swift Testing and XCTest allow us to test asynchronous code built with Swift concurrency by marking tests as async. This means we can wait for concurrent code to complete...

Both Swift Testing and XCTest give us three main options for handling errors in tests: we can consider them immediate failures, we can handle them internally and make our own asser...

When you're dealing with older concurrency code that relies on callback functions that get run when some work completes rather than using Swift concurrency's async/await ...

Concurrent Swift code often streams values over time rather than returning them all at once, so it's important to be able to write tests to check an AsyncStream, AsyncSeq...

Both Swift Testing and XCTest have simple mechanisms for controlling how long tests should be allowed to run before being considered a failure. This is critically important for con...

Swift Testing and XCTest behave differently when it comes to running tests in parallel: unless you say otherwise, Swift Testing will run both synchronous and asynchronous tests on ...

Swift Testing's parameterized tests allow us to send multiple values into a single test, and they'll be run in parallel for maximum performance. If you don't want this – if you wa...

Fetching JSON from the network and using Codable to convert it into native Swift objects is probably the most common task for any Swift developer, usually followed by dis...

Sure, all your tests pass, but how can you make sure your app functions properly? Most large projects have a solution called a release checklist, and here I want to share mine wit...

We're going to build a macOS app that lets users write Markdown and see exactly how it looks as they type. More importantly, we're going to do so using test-driven development, so ...