How does homebrew customize the installation instructions in GitHub Packages to be brew install <formula>?

[kevinlul]

Output of brew config

N/A

Output of brew doctor

N/A

Description of issue

Normally for the container registry, GitHub would suggest the command docker pull ghcr.io/IMAGE_NAME. However, for bottles, it actually shows brew install FORMULA, though switching to the OS / Arch tab shows the docker pull commands again.

e.g. https://github.com/Homebrew/homebrew-core/pkgs/container/core%2Fsqlite/221454310?tag=3.46.0

How is this accomplished?

[SMillerDev]

I suspect it's https://github.com/Homebrew/brew/blob/62ebd31942d4fae7fc2b14f765a2e9c41a6b373b/Library/Homebrew/github_packages.rb#L305

[kevinlul]

So it's a custom arrangement with GitHub, setting label com.github.package.type to homebrew_bottle?

[SMillerDev]

I have no idea, but that sounds plausible. You'd really have to ask GitHub how their UI works.