Remove portable ruby bin from PATH

[cho-m]

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Fixes #21109

This PR removes portable Ruby from PATH as parts of brew are written expecting only system paths like

brew/Library/Homebrew/extend/os/linux/cleanup.rb

Line 15 in 07a983c

rubies = [which("ruby"), which("ruby", ORIGINAL_PATHS)].compact

I am not entirely sure on setup_gem_environment! change, but it restores original behavior before 60fa368#diff-a1a5395d198aee1fb8c45c74bf9dd49ef5734887a17ee84000badc7d58b82e98L43 (called via install_bundler!)

This mainly is used to avoid a failing test (utils/ruby_check_version_script_spec.rb).

Though maybe the test shouldn't be using Ruby from PATH as that is not how we interact with the script. We usually call the script like <path/to/ruby> ruby_check_version_script_spec.rb ... so it doesn't matter whether or not portable Ruby is on the PATH.

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EDIT: After thinking over above, will just adjust test rather than adding setup_gem_environment!. Also in line with the Copilot review that setup_gem_environment! has side effects that we may not have intended.

May need to keep an eye out for unexpected failures though if any code is expecting portable Ruby on PATH.

[Copilot]

Pull Request Overview

This PR removes the portable Ruby bin directory from PATH in the shell script (ruby.sh) and adds a call to setup_gem_environment! in the valid_gem_groups method to restore gem environment setup through Ruby code instead. The main motivation is to fix a failing test (ruby_check_version_script_spec.rb) that was picking up the portable Ruby from PATH.

Key Changes

• Removed PATH modification in shell script that added portable Ruby bin directory
• Added setup_gem_environment! call at the start of valid_gem_groups method
• Shifts PATH setup responsibility from shell to Ruby code

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
Library/Homebrew/utils/ruby.sh	Removes the line that adds portable Ruby bin directory to PATH after installing bundler
Library/Homebrew/utils/gems.rb	Adds setup_gem_environment! call to valid_gem_groups to ensure gem environment is set up before querying bundler groups

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[Copilot]

Pull Request Overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

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[MikeMcQuaid]

Looks good, thanks @cho-m!