WWDC 2026 - Migrate to Swift Testing: What Actually Means for Your Test Suite

Swift Testing shipped with Xcode 16 back in 2024. Swift Testing was built from the ground up for Swift. That means Swift concurrency is a first-class citizen, test cases run in parallel by default, and the API surface is dramatically smaller than XCTest's forty-plus assertion functions. One macro, #expect , replaces most of them. If you are still on XCTest, you have probably felt the friction: class inheritance for every test suite, function names that must start with test , assertion messages that tell you what the values were but not where the expression came from. Swift Testing fixes all of this. That said, you do not need to migrate everything at once, and WWDC 2026 is emphatic about this. The Migration Strategy: Small Chunks, No Big Bang The session opens with something refreshing: permission to be slow about this. The recommended approach is to leave your existing XCTests where they are and start using Swift Testing only for new tests. Both frameworks can coexist in the same target and even the same file. You do not need a separate test target, and you do not need a migration sprint. The one rule: Swift Testing tests cannot live inside XCTestCase subclasses. Everything else is fair game. Raw Identifiers for Readable Test Names One small quality-of-life improvement worth knowing about from the start: Swift supports raw identifiers using backticks, and Swift Testing takes full advantage of this. import Testing @testable import DemoApp @Test func ` Default climate : tropical ` () async throws { let fruit = Fruit ( name : "Coconut" ) #expect(fruit.climate == .tropical) } No more testDefaultClimateTropical or dealing with camelCase names in test output. The test name is the test name. Interoperability: The Key to Reusing Your Helper Code This is the main new story in WWDC 2026 and the feature that makes incremental migration actually work. The problem: you have test helper functions that wrap XCTFail . You want to call them from new Swift Testing tests. Previously,