Skip untrusted cleanup formulae

[MikeMcQuaid]

Fixes #22551

• Avoid aborting brew cleanup when cache checks cannot load an installed formula from an untrusted tap.
• Warn that the tap formula is not trusted so users know why cleanup skipped that formula's cache eligibility check.

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[Copilot]

Pull request overview

This pull request adjusts brew cleanup cache staleness checks to avoid aborting when an installed formula can’t be loaded due to tap trust restrictions, and adds test coverage for that scenario.

Changes:

• Rescue Homebrew::UntrustedTapError during cache staleness checks so brew cleanup can continue.
• Emit a warning when an untrusted tap formula prevents determining cache eligibility.
• Add an RSpec example asserting untrusted-formula cache entries are skipped and not removed.

Reviewed changes

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

File	Description
Library/Homebrew/cleanup.rb	Skip cache staleness evaluation when loading an installed formula raises UntrustedTapError, warning instead of aborting.
Library/Homebrew/test/cleanup_spec.rb	Adds a regression test ensuring untrusted formula loading doesn’t remove the cache entry and warns to stderr.

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[github-code-quality]

Code Coverage Overview

Languages: Ruby

Ruby / code-coverage/simplecov

The overall coverage in the trust-fixes branch remains at 78%, unchanged from the main branch.

Show a code coverage summary of the most impacted files.

File	main c6a08de	trust-fixes 08c9669	+/-
services/system/systemctl.rb	93%	87%	-6%
utils/tty.rb	92%	91%	-1%
download_queue.rb	74%	73%	-1%
cleanup.rb	83%	83%	0%
dev-cmd/formula-analytics.rb	17%	18%	+1%
bundle/subcommand.rb	94%	96%	+2%
manpages.rb	50%	54%	+4%
services/system.rb	81%	85%	+4%
services/cli.rb	62%	69%	+7%
extend/pathname.rb	75%	82%	+7%

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_{Updated June 05, 2026 17:12 UTC
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