Swift Testing documentation

March 18, 2026 ยท View on GitHub

API and usage guides

The detailed documentation for Swift Testing can be found on the Swift Package Index. There, you can delve into comprehensive guides, tutorials, and API references to make the most out of this package.

This documentation is generated using DocC and is derived from symbol documentation in this project's source code as well as supplemental content located in the Sources/Testing/Testing.docc/ directory.

Obtaining Swift Testing discusses the various ways Swift Testing is distributed and offers recommended usage workflows.

Vision document and API proposals

The Vision document for Swift Testing offers a comprehensive discussion of the project's design principles and goals.

Feature and API proposals for Swift Testing are stored in the swift-evolution repository in the proposals/testing/ subdirectory, and new proposals should use the testing template there.

Development and contribution

  • The top-level README gives a high-level overview of the project, shows current CI status, lists the support status of various platforms, and more.
  • Contributing provides guidance for developing and making project contributions.
  • Porting includes advice and instructions for developers who are porting Swift Testing to a new platform.
  • Style Guide describes this project's guidelines for code and documentation style.
  • SPI groups in Swift Testing describes when and how the testing library uses Swift SPI.

Experimental platform support

Testing library ABI

The ABI directory contains documents related to Swift Testing's ABI: that is, parts of its interface that are intended to be stable over time and can be used without needing to write any code in Swift:

  • ABI/EventStreamHandling.md contains information about Swift Testing's SPI that you can use when working with the library's JSON event stream.
  • ABI/JSON.md contains Swift Testing's JSON specification that can be used by tools to interact with Swift Testing either directly or via the swift test command-line tool.
  • ABI/TestContent.md documents the section emitted by the Swift compiler into test products that contains test definitions and other metadata used by Swift Testing (and extensible by third-party testing libraries.)