Supporting Android

[mortenbekditlevsen]

Hi there,
I am trying to build combine-schedulers for Android, but cross-compiling from macOS.

By updating dependencies for swift-concurrency-extras to 1.3.2 and xctest-dynamic-overlay to 1.7.0 I can get the package compiling by adding the OpenCombineSchedulers trait.

Unfortunately traits don't appear to work transitively, so when including combine-schedulers as a dependency to swift-dependencies (which is my goal to get building for Android), then I can't pass the trait.

And as I am building on macOS, the following lines in the Package.swift have no effect:

#if !canImport(Darwin)
  package.traits.insert(
    .default(enabledTraits: ["OpenCombineSchedulers"])
  )
#endif

Would it be sufficient to check for the platform when conditionally depending on OpenCombineShim?

So:

        .product(
          name: "OpenCombineShim",
          package: "OpenCombine",
          condition: .when(platforms: [.linux, .android])
        ),

rather than:

        .product(
          name: "OpenCombineShim",
          package: "OpenCombine",
          condition: .when(platforms: [.linux, .android], traits: ["OpenCombineSchedulers"])
        ),

?