How can I migrate from XCTest to the new swift test package

To migrate from XCTest to the new Swift Testing package, you can follow these steps:

1. Add a Test Bundle Target: If you haven't already, add a test bundle target to your project. In Xcode, choose File > New > Target, then search for Unit Testing Bundle in the test section. Swift Testing is now the default choice for this template in Xcode 16.

2. Understand the Differences: Swift Testing has some similarities to XCTest but also important differences. For example, tests in XCTest are any method whose name begins with test, while Swift Testing uses the @test attribute to denote them explicitly. Swift Testing supports more kinds of functions, including instance methods, static methods, and global functions.

3. Translate Assertions: Avoid calling XCTest assertion functions from Swift Testing tests, or the opposite. Check out the documentation on migrating a test from XCTest for details on how to translate assertions and handle asynchronous waiting conditions.

4. Parameterize Tests: When migrating multiple XCTest methods with a similar structure, you can consolidate them into one parameterized test. Swift Testing allows you to use tags to organize and filter your tests and to use arguments to avoid duplicating the same test for multiple inputs.

5. Setup and Teardown: In Swift Testing, use the type's initializer for setup logic, which can be async or throw. For teardown logic, include a deinitializer, which can only be used when the suite type is an actor or class.

6. Coexistence: XCTest and Swift Testing tests can coexist in a single target, so you can migrate incrementally without needing to create a new target first.

For more detailed guidance, you can refer to the session Meet Swift Testing (17:35).

Relevant Sessions

• Meet Swift Testing
• Platforms State of the Union
• What’s new in Swift