Homebrew formula for the CLI should use libexec

[Lublanski]

Fixes #46866

Summary
This PR updates the spring-boot Homebrew formula to install JARs under libexec instead of lib.
This change follows Homebrew best practices to avoid conflicts between packages when HOMEBREW_DEVELOPER=true is enabled.

Changes

• Updated the formula to install all JARs into libexec.
• Wrapped the spring binary with write_env_script to ensure correct runtime paths.
• Verified shell completion installation for Bash and Zsh.

Verification
Tested locally with:
HOMEBREW_DEVELOPER=true brew install --build-from-source spring-boot

Result: No warnings when running with HOMEBREW_DEVELOPER=true, and the CLI works as expected.

Before change

After change

[snicoll]

Please don't paste screenshots, they aren't very helpful. What did you do locally for the command to succeed? It can't work as version and hash aren't provided. I want to make sure I am running the same as you.

[Lublanski]

Please don't paste screenshots, they aren't very helpful. What did you do locally for the command to succeed? It can't work as version and hash aren't provided. I want to make sure I am running the same as you.

@snicoll
Sorry for screenshots.
In the fix branch, i used:

class SpringBoot < Formula
  homepage 'https://spring.io/projects/spring-boot'
  url 'https://repo.maven.apache.org/maven2/org/springframework/boot/spring-boot-cli/3.5.6/spring-boot-cli-3.5.6-bin.tar.gz'
  version '3.5.6'
  sha256 '3ac9314100c474ddad1c4ae04a85404383817d6f748820980e26ccbe55393bbe'
  head 'https://github.com/spring-projects/spring-boot.git', :branch => "main"

And running the command HOMEBREW_DEVELOPER=true brew install --build-from-source spring-boot

what values ​​for $repo, $version and $hash did you use to make it not work?

[snicoll]

what values ​​for $repo, $version and $hash did you use to make it not work?

I didn't do anything. I wanted to know what you did. With the value above, this is what I get

HOMEBREW_DEVELOPER=true brew install --build-from-source ./spring-boot.rb
Error: Failed to load cask: ./spring-boot.rb
Cask 'spring-boot' is unreadable: wrong constant name #<Class:0x000000013ced28c0>
Warning: Treating ./spring-boot.rb as a formula.
==> Fetching downloads for: spring-boot
✔︎ Formula spring-boot (3.5.6)
🍺  /opt/homebrew/Cellar/spring-boot/3.5.6: 12 files, 8.0MB, built in 1 second
==> Running `brew cleanup spring-boot`...
Disable this behaviour by setting `HOMEBREW_NO_INSTALL_CLEANUP=1`.
Hide these hints with `HOMEBREW_NO_ENV_HINTS=1` (see `man brew`).
==> Caveats
zsh completions have been installed to:
  /opt/homebrew/share/zsh/site-functions

brew --version
Homebrew 4.6.17-67-g00001be

I have no idea what wrong constant name #<Class:0x000000013ced28c0> is and that's why I wanted the instruction to reproduce what works for you.

[Lublanski]

what values ​​for $repo, $version and $hash did you use to make it not work?

I didn't do anything. I wanted to know what you did. With the value above, this is what I get

HOMEBREW_DEVELOPER=true brew install --build-from-source ./spring-boot.rb
Error: Failed to load cask: ./spring-boot.rb
Cask 'spring-boot' is unreadable: wrong constant name #<Class:0x000000013ced28c0>
Warning: Treating ./spring-boot.rb as a formula.
==> Fetching downloads for: spring-boot
✔︎ Formula spring-boot (3.5.6)
🍺  /opt/homebrew/Cellar/spring-boot/3.5.6: 12 files, 8.0MB, built in 1 second
==> Running `brew cleanup spring-boot`...
Disable this behaviour by setting `HOMEBREW_NO_INSTALL_CLEANUP=1`.
Hide these hints with `HOMEBREW_NO_ENV_HINTS=1` (see `man brew`).
==> Caveats
zsh completions have been installed to:
  /opt/homebrew/share/zsh/site-functions

brew --version
Homebrew 4.6.17-67-g00001be

I have no idea what wrong constant name #<Class:0x000000013ced28c0> is and that's why I wanted the instruction to reproduce what works for you.

@snicoll
Thanks for testing this!

Are you using macOS?
The error message:

Error: Failed to load cask: ./spring-boot.rb  
Cask 'spring-boot' is unreadable: wrong constant name #<Class:...>  

can happens on macOS because Homebrew first tries to interpret any local .rb file as a Cask (used for GUI apps).

On Linux this doesn’t happen, so the formula installs fine.

To fix this on macOS, please run the command with the --formula flag so Homebrew treats it correctly:
HOMEBREW_DEVELOPER=true brew install --formula --build-from-source ./spring-boot.rb

That will force Homebrew to use the Formula loader instead of the Cask loader and should work as expected.

[snicoll]

Are you using macOS?

Yes. Thanks for the hint! I am on the same page as you now.

[Lublanski]

@snicoll
Thank you for accepting the adjustment. I'm glad I was able to contribute. I'll look for new, simple issues to try to contribute more.