[hyuraku]

MacOS.undeletable? only matches exact paths in UNDELETABLE_PATHS. So ~/Library/Keychains itself is protected, but a file inside it such as ~/Library/Keychains/login.keychain-db is not. A zap trash: or uninstall delete: stanza, or a pkg uninstall, could still remove it. There was a TODO asking for a way to protect everything under a directory.

This change adds UNDELETABLE_CONTAINERS. undeletable? now also returns true for these directories and any path under them. The list has three directories that are already in UNDELETABLE_PATHS and hold private user data: ~/Library/Keychains (passwords and keys), ~/Library/Messages (message history) and ~/Library/Application Support/com.apple.TCC (privacy permissions).

No official cask is affected as of 2026-10-26. None of the 7,814 casks in homebrew/cask (at Homebrew/homebrew-cask@1d6a12f) point to a path under these directories. The new tests check a path inside ~/Library/Keychains and a sibling path (~/Library/Keychains2/...) to make sure the prefix match does not catch the sibling.

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• I did not use AI/LLM to create this PR, or I disclosed the tool/model below and reviewed its output; I did not attribute commits to AI and will answer maintainer questions and review comments myself without AI/LLM.

AI (Claude Code) assisted in writing the code and tests, and searched homebrew/cask for affected casks. I reviewed the change and ran brew lgtm locally.

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[coderabbitai]

No actionable comments were generated in the recent review.

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• Library/Homebrew/cask/macos.rb

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📝 Summary

Summary by CodeRabbit

• Bug Fixes
  • Deletion protection now covers files and folders within keychain, Messages, and privacy-related application data locations, as well as the locations themselves.
  • Paths that resolve through a symlink into a protected location are also covered by deletion protection.
  • Similarly named folders outside those protected locations remain unaffected, so protection applies only to the designated locations and their contents.

The undeletable-path check now tests expanded paths and, when the parent exists, resolved paths. It protects paths within three Library containers and retains checks for explicitly undeletable paths. Specs cover keychain paths and a path reached through a symlink.

Changes: Undeletable paths

Layer / File(s)	Summary
Container checks and coverage Library/Homebrew/cask/macos.rb, Library/Homebrew/test/cask/macos_spec.rb	A private set defines three protected Library containers. undeletable? checks expanded and resolved path candidates for exact matches or containment. Specs check a login keychain path, a similarly named path under Keychains2, and an Applications child reached through a symlink.

Priority: Normal

Merge Risk: Minimal · up to d5b65

The protected directories are checked before uninstall deletion. No merge-blocking risk remains identified.

Pre-merge checks: 4

Check name	Status	Explanation
Title check		The title clearly identifies the main change: adding undeletable container directories for cask macOS handling.
Description check		The description accurately explains the existing limitation, the new container behaviour, the protected directories, test coverage, and validation performed.
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

• Autofix · Keep fixing CodeRabbit findings and required CI, and resolving merge conflicts

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[coderabbitai]

Actionable comments posted: 1

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[MikeMcQuaid]

Thanks, looks good except Code Rabbit comment needs addressed!

[coderabbitai]

Actionable comments posted: 1

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[MikeMcQuaid]

@hyuraku will review again when all coderabbit comments addressed!

[MikeMcQuaid]

Thanks!