CMake.md

Building with CMake

Add Swift Testing to your project

Add Swift Testing to your project using the standard FetchContent or find_package mechanism, as appropriate for your project. For example:

include(FetchContent)
FetchContent_Declare(SwiftTesting
  GIT_REPOSITORY https://github.com/swiftlang/swift-testing.git
  GIT_TAG main)
FetchContent_MakeAvailable(SwiftTesting)

Define a test executable

To build a test executable using Swift Testing, define an executable target of the form [YOURPROJECT]PackageTests, set the executable suffix to be .swift-testing, and link to the Testing target as well as any project targets you wish to test.

The following example shows what this might look like for a hypothetical project called Example:

add_executable(ExamplePackageTests
  ExampleTests.swift
  ...)
set_target_properties(ExamplePackageTests PROPERTIES
  SUFFIX .swift-testing)
target_link_libraries(ExamplePackageTests PRIVATE
  Example
  Testing
  ...)

When building the test executable, the code you're testing will need to be built with -enable-testing. This should only be enabled for testing, for example:

include(CTest)
if(BUILD_TESTING)
  add_compile_options($<$<COMPILE_LANGUAGE:Swift>:-enable-testing>)
endif()

Add an entry point

You must include a source file in your test executable target with a @main entry point. The example main below requires the experimental Extern feature. The declaration of swt_abiv0_getEntryPoint could also be written in a C header file with its own module.modulemap.

typealias EntryPoint = @convention(thin) @Sendable (_ configurationJSON: UnsafeRawBufferPointer?, _ recordHandler: @escaping @Sendable (_ recordJSON: UnsafeRawBufferPointer) -> Void) async throws -> Bool

@_extern(c, "swt_abiv0_getEntryPoint")
func swt_abiv0_getEntryPoint() -> UnsafeRawPointer

@main struct Runner {
    static func main() async throws {
        nonisolated(unsafe) let configurationJSON: UnsafeRawBufferPointer? = nil
        let recordHandler: @Sendable (UnsafeRawBufferPointer) -> Void = { _ in }

        let entryPoint = unsafeBitCast(swt_abiv0_getEntryPoint(), to: EntryPoint.self)

        if try await entryPoint(configurationJSON, recordHandler) {
            exit(EXIT_SUCCESS)
        } else {
            exit(EXIT_FAILURE)
        }
    }
}

For more information on the input configuration and output records of the ABI entry point, refer to the ABI documentation

Integrate with CTest

To run your test using CTest, add the test using the appropriate command line.

include(CTest)
add_test(NAME ExamplePackageTests
  COMMAND ExamplePackageTests)