Only use MachOShim/ELFShim when required

[MikeMcQuaid]

Not including this globally in Pathname speeds up the creation of other Pathname objects by ~200x making all of Homebrew faster.

[Copilot]

Pull Request Overview

This PR optimizes Homebrew's performance by removing the global inclusion of MachOShim and ELFShim in the Pathname class. Instead, these modules are now explicitly extended only when needed on individual Pathname instances, resulting in ~200x faster Pathname object creation.

• Removed global MachOShim/ELFShim inclusion from Pathname class
• Updated code to explicitly extend Pathname instances with MachOShim or ELFShim where binary file operations are needed
• Restructured Linux cleaner module to match the Mac cleaner pattern with proper namespacing

Reviewed Changes

Copilot reviewed 11 out of 13 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
Library/Homebrew/utils/linkage.rb	Added explicit extension of Pathname with OS-specific shims before checking dynamic libraries
Library/Homebrew/test/support/helper/fixtures.rb	Added explicit MachOShim extension to test fixture paths
Library/Homebrew/test/os/mac/mach_spec.rb	Added explicit MachOShim extension to test pathnames
Library/Homebrew/extend/pathname.rb	Removed global OS-specific pathname extension require
Library/Homebrew/extend/os/pathname.rb	Deleted file that globally included OS-specific pathname extensions
Library/Homebrew/extend/os/mac/keg_relocate.rb	Added explicit MachOShim extension before checking Mach-O file properties
Library/Homebrew/extend/os/mac/extend/pathname.rbi	Deleted type signature file for global MachOShim inclusion
Library/Homebrew/extend/os/mac/extend/pathname.rb	Deleted file that globally prepended MachOShim to Pathname
Library/Homebrew/extend/os/mac/cleaner.rb	Added explicit MachOShim extension before checking if path is a Mach-O executable
Library/Homebrew/extend/os/linux/keg_relocate.rb	Added explicit ELFShim extension before checking ELF file properties
Library/Homebrew/extend/os/linux/extend/pathname.rbi	Deleted type signature file for global ELFShim inclusion
Library/Homebrew/extend/os/linux/extend/pathname.rb	Deleted file that globally prepended ELFShim to Pathname
Library/Homebrew/extend/os/linux/cleaner.rb	Restructured into OS::Linux::Cleaner module and added explicit ELFShim extension

Files not reviewed (2)

• Library/Homebrew/extend/os/linux/extend/pathname.rbi: Language not supported
• Library/Homebrew/extend/os/mac/extend/pathname.rbi: Language not supported

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[Rylan12]

Nice, makes sense to me once CI/copilot comments are resolved!

[Copilot]

Pull Request Overview

Copilot reviewed 25 out of 27 changed files in this pull request and generated 1 comment.

Files not reviewed (2)

• Library/Homebrew/extend/os/linux/extend/pathname.rbi: Language not supported
• Library/Homebrew/extend/os/mac/extend/pathname.rbi: Language not supported

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[Rylan12]

This is a really nice improvement!

[Copilot]

Pull Request Overview

Copilot reviewed 26 out of 28 changed files in this pull request and generated 4 comments.

Files not reviewed (2)

• Library/Homebrew/extend/os/linux/extend/pathname.rbi: Language not supported
• Library/Homebrew/extend/os/mac/extend/pathname.rbi: Language not supported

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[Copilot]

Pull Request Overview

Copilot reviewed 26 out of 28 changed files in this pull request and generated 1 comment.

Files not reviewed (2)

• Library/Homebrew/extend/os/linux/extend/pathname.rbi: Language not supported
• Library/Homebrew/extend/os/mac/extend/pathname.rbi: Language not supported

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[Copilot]

Pull request overview

Copilot reviewed 54 out of 57 changed files in this pull request and generated 1 comment.

Files not reviewed (3)

• Library/Homebrew/extend/os/linux/extend/pathname.rbi: Language not supported
• Library/Homebrew/extend/os/mac/extend/pathname.rbi: Language not supported
• Library/Homebrew/extend/pathname.rbi: Language not supported

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[Copilot]

Pull request overview

Copilot reviewed 54 out of 57 changed files in this pull request and generated no new comments.

Files not reviewed (3)

• Library/Homebrew/extend/os/linux/extend/pathname.rbi: Language not supported
• Library/Homebrew/extend/os/mac/extend/pathname.rbi: Language not supported
• Library/Homebrew/extend/pathname.rbi: Language not supported

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[Copilot]

Pull request overview

Copilot reviewed 54 out of 57 changed files in this pull request and generated no new comments.

Files not reviewed (3)

• Library/Homebrew/extend/os/linux/extend/pathname.rbi: Language not supported
• Library/Homebrew/extend/os/mac/extend/pathname.rbi: Language not supported
• Library/Homebrew/extend/pathname.rbi: Language not supported

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[Copilot]

Pull request overview

Copilot reviewed 54 out of 57 changed files in this pull request and generated 1 comment.

Files not reviewed (3)

• Library/Homebrew/extend/os/linux/extend/pathname.rbi: Language not supported
• Library/Homebrew/extend/os/mac/extend/pathname.rbi: Language not supported
• Library/Homebrew/extend/pathname.rbi: Language not supported

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[MikeMcQuaid]

Maintainers: this shouldn't break anything but, if it does, it should be fairly simple to use MachOPathname.wrap (for macOS-only code) or ELFPathname.wrap (for Linux-only code) or BinaryPathname.wrap (otherwise).