XCTest vs Swift Testing: what changed and how to migrate?
The gist
Swift Testing is Apple's framework built on macros and Swift Concurrency (Xcode 16, Swift 6). A test is any function marked @Test, a group is a type marked @Suite (usually a struct), checks are #expect and #require. It does not replace XCTest entirely: both frameworks live in the same test target, so migration happens gradually, file by file.
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