Add support for Swift Macros

[keith]

No description provided.

[chiragramani]

Thanks for putting this up! 🙏🏼
I was trying to build the example but it failed with the following error:

bazel build :main

Compiling Swift module //:lib failed: (Exit 1): worker failed: error executing command (from target //:lib) bazel-out/darwin_arm64-opt-exec-2B5CBBC6/bin/external/build_bazel_rules_swift/tools/worker/worker swiftc @bazel-out/darwin_arm64-fastbuild/bin/lib.swiftmodule-0.params
error: emit-module command failed with exit code 1 (use -v to see invocation)
<unknown>:0: error: error opening input file 'bazel-out/darwin_arm64-opt-exec-2B5CBBC6/bin/macrosplugin#macros' (No such file or directory)
<unknown>:0: error: error opening input file 'bazel-out/darwin_arm64-opt-exec-2B5CBBC6/bin/macrosplugin#macros' (No such file or directory)
Target //:main failed to build
Use --verbose_failures to see the command lines of failed build steps.
INFO: Elapsed time: 0.305s, Critical Path: 0.16s
INFO: 2 processes: 2 internal.
FAILED: Build did NOT complete successfully

The file bazel-out/darwin_arm64-opt-exec-2B5CBBC6/bin/macrosplugin is present but from the params file - it's looking for bazel-out/darwin_arm64-opt-exec-2B5CBBC6/bin/macrosplugin#macros which is not present.

[keith]

hrm what's your build command? can you make sure you're on the latest commit here too?

[chiragramani]

hrm what's your build command? can you make sure you're on the latest commit here too?

Yes, on the latest commit.

commit 3674f6fc27877af848cf55e10045587c6ac950ce (HEAD -> macro_test, origin/ks/add-support-for-swift-macros)
Author: Keith Smiley <keithbsmiley@gmail.com>
Date:   Wed Jun 14 16:41:11 2023 -0700

    Add test target example

Build command: building the main binary. //examples/macros:main

bazel build :main

[keith]

Could you be using an old version of Xcode / Swift?

[keith]

(that's the same error CI has for an old version)

[chiragramani]

Could you be using an old version of Xcode / Swift?

Oh yes, you are right, Xcode was switched, sorry for the wrong call. Works all great now!

[jafara]

whats the status of landing this?

[keith]

I think we'll likely wait a bit longer, maybe 1 more beta? to make sure things still work

[tinder-tannerbennett]

@keith Everything still working with the latest betas? 😄

[brentleyjones]

I believe an updated version of #1061 is what will eventually land.

[keith]

#1061