How smart is it?

[dabrahams]

I notice that when I ask for swift 5.9 on GitHub's macos-latest runner, this action installs Swift. Is that because the runner has an earlier version, or is there a missing optimization here?

Thanks!

P.S. Love the very usable interface to installing on any platform. Thanks for making this available.

[soumyamahunt]

Glad to know you find this action useful. I just noticed this discussion so here is the rationale.

Swift 5.9 requires Xcode 15 as mentioned in swift.org. The macos-latest runner is listed to be using macos-12 runner as of now, which doesn't have Xcode 15 installed. Hence the action downloads Swift 5.9.

This action won't download Swift if required Xcode version is installed and will just switch the default Xcode version to that installation. i.e. for macos-13 Swift 5.9 won't be installed, you can also see this in action as part of integration test.

[dabrahams]

Yeah, I eventually found out macos-latest was 12, not 13 (how suprising!) Sorry for not closing this issue.

That said, I don't think

Swift 5.9 requires Xcode 15

is true. You can install a Swift 5.9 release on a machine with no Xcode installed at all. In fact, I'm pretty sure Xcode 15 doesn't run on macOS 12, so when your action downloads Swift 5.9 on macos-latest that Swift runs without Xcode 15 too.

[soumyamahunt]

Agree that "requires" is the wrong word to use here, what I meant was Xcode 15 comes with Swift 5.9 and in presence of Xcode 15 it won't be reinstalled by this action.