Enable CI builds for aarch64-macos

[yvt]

Closes #1647.

A preview CI run based on this patch and the built artifacts can be found at https://github.com/yvt/helix/actions/runs/2709143241.

[archseer]

Do we need to do anything special to support this in the homebrew tap? https://github.com/helix-editor/homebrew-helix/blob/master/Formula/helix.rb

[archseer]

Looks like we need a conditional: https://github.com/golangci/homebrew-tap/blob/bb0e7c6fa14d7fd771e1a5941f5e3ca85a15624c/Formula/golangci-lint.rb#L11-L40=

[yvt]

I believe switching url and sha256 by CPU architectures is all we need to do.

on_macos do
  if Hardware::CPU.arm?
    url "https://github.com/helix-editor/helix/releases/download/#{version}/helix-#{version}-aarch64-macos.tar.xz"
    sha256 "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
  end
  if Hardware::CPU.intel?
    url "https://github.com/helix-editor/helix/releases/download/#{version}/helix-#{version}-x86_64-macos.tar.xz"
    sha256 "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
  end
end

[the-mikedavis]

When would target be different from BUILD_TARGET? Both come from TARGET environment variables in build scripts, BUILD_TARGET from the helix-loader crate's build script and target from helix-term's

[yvt]

When helix_loader::build_grammars is being used for cross compilation.

BUILD_TARGET represents the target on which the code of helix-loader runs. helix-term's build script (which has helix-loader as build-dependency) needs to use helix-loader to cross-compile for helix-term's target, which may be different from BUILD_TARGET.

E.g., when cross-compiling helix-term to an aarch64 target on an x86_64 host, two binaries of helix-loader are built:

• One binary for aarch64 target for use by helix-term's main crate (normal dependency)

  • helix-loader's build script runs with TARGET = "aarch64"
  • Hence, env!("BUILD_TARGET") = "aarch64"
  • helix-term's main crate code passes target = None because it wants to compile grammars for the current host = helix-loader's build target

• One binary for x86_64 target for use by helix-term's build script (build dependency)

  • helix-loader's build script runs with TARGET = "x86_64"
  • Hence, env!("BUILD_TARGET") = "x86_64"
  • helix-term's build script passes target = "aarch64" because it wants to cross-compile grammars for helix-term's build target, not the host on which the build script runs

[the-mikedavis]

Looks good to me then :)

I tried out your example run artifacts on an aarch64-macos machine and it all works great 🎉

Thanks for working on this

[archseer]

Thanks @yvt!