Dependency injection test implementation

[mallexxx]

Macros are an experimental feature, so you will need a custom Swift toolchain and some extra compiler flags. The Xcode project in this repository is a good starting point. To use it:

1. Download a development snapshot of the compiler from Swift.org from May 10, 2023 or later. At present, we only have these working on macOS, but are working to get other platforms working with other build systems.
2. Clone the repo:

   git clone -b dependency-injection github.com:mallexxx/swift-macro-dependency-injection.git
   

3. Build the example project in Xcode:
   a. Open MacroExamples.xcodeproj in Xcode
   b. Go to the Xcode -> Toolchains menu and select the development toolchain you downloaded.
   c. Make sure the DependencyInjection scheme is selected, then build and run!

• !!! The first build will fail! Build again. Then build again!

• Head to the DependencyInjection/main.swift for the sources

• uncomment DependencyInjection/main.swift:150 to see how compile-time dependency graph checking works