SwiftTests

SwiftTests is a new testing framework introduced by Apple, designed specifically for Swift. Here are some key points about SwiftTests from the WWDC sessions:

1. Introduction and Features:

   • SwiftTests is built from the ground up for Swift, featuring expressive APIs that make it simple to write tests. It is cross-platform and open-source, hosted on GitHub (Platforms State of the Union).
   • It supports traits for specifying information either per test or per suite and takes a different approach to parallelization by running in-process using Swift concurrency (Meet Swift Testing).

2. Comparison with XCTest:

   • SwiftTests uses the @test attribute to denote test functions explicitly, unlike XCTest which uses method names starting with test.
   • It supports more kinds of functions, including instance methods, static methods, and global functions.
   • SwiftTests uses two basic macros, expect and require, for assertions, which are more flexible compared to the many specialized functions in XCTest (Meet Swift Testing).

3. Concurrency and Initialization:

   • Test functions integrate seamlessly with Swift concurrency, supporting async/await and actor isolation.
   • SwiftTests uses the type's initializer for setup logic, which can be async or throw, and a deinitializer for cleanup (Meet Swift Testing).

4. Organizing Tests:

   • Tests can be grouped into subgroups via nested types, and SwiftTests encourages the use of structs to isolate state and avoid unintentional state sharing (Meet Swift Testing).
   • It includes a flexible tagging system to help organize tests and test plans with tags, allowing selective test runs (Platforms State of the Union).

5. Common Workflows:

   • SwiftTests supports parameterized testing, allowing tests to be repeated with different arguments.
   • It also supports conditions for running tests only in certain circumstances, such as on specific devices or environments (Meet Swift Testing).

6. Integration and Migration:

   • SwiftTests can coexist with XCTest in a single target, allowing incremental migration.
   • It is integrated into major Apple platforms and supports Linux and Windows, providing a consistent testing experience across different environments (Meet Swift Testing).

For more detailed information, you can refer to the sessions:

• Meet Swift Testing
• Go further with Swift Testing
• Platforms State of the Union
• What’s new in Xcode 16