[hyuraku]

brew ruby -e 'p [Version.new("1.0.0") <=> Version.new("1.0rc1"), Version.new("1.0rc1") <=> Version.new("1.0.0")]'
# before: [0, -1]
# after:  [1, -1]

The loop stops when the left index reaches the end, so after skipping a padding 0 it never compares the right side's rc1. Now it runs until both sides reach the end. Because of this bug, brew outdated does not
treat 1.0.0 as newer than an installed 1.0rc1.

Only pairs that were already asymmetric change, and each one now matches the swapped call. I checked this on all pairs of generated strings and of the formula and cask versions in the API data. I added a test for this case.

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• Have you followed our Contributing guidelines?
• Have you checked for other open Pull Requests for the same change?
• Have you explained what your changes do? Performance claims (e.g. "this is faster") must include brew benchmark results.
• Have you explained why you'd like these changes included, not just what they do?
• For bug fixes, have you given step-by-step brew commands to reproduce the bug?
• Have you written new tests (excluding integration tests)? Here's an example.
• Have you successfully run brew lgtm (style, typechecking and tests) locally?

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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; every commit has a human author or co-author and I will answer maintainer questions and review comments myself without AI/LLM.

AI (Claude Code) found this bug with a script that checks ordering laws on many version strings, and drafted the fix and test. I reviewed the change and ran brew lgtm locally.

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[coderabbitai]

No actionable comments were generated in the recent review.

Summary

Summary by CodeRabbit

• Bug Fixes
  • Corrected version comparisons so that a stable release sorts after its release candidate.

Version#<=> now compares tokens until both versions are exhausted. A test checks that release 1.0.0 sorts after release candidate 1.0rc1.

Changes: Version comparison

Layer / File(s)	Summary
Token comparison and regression test Library/Homebrew/version.rb, Library/Homebrew/test/version_spec.rb	Version#<=> continues comparing tokens until both lists are exhausted. The test asserts that 1.0.0 sorts after 1.0rc1.

Merge Risk: Minimal · up to c5039

This change makes version comparison symmetric, so 1.0.0 is correctly treated as newer than 1.0rc1. No actionable merge risk remains.

Pre-merge checks: 4

Check name	Status	Explanation
Title check		The title clearly identifies the main change: fixing asymmetric version comparison involving trailing zeroes.
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.
Description check		The description clearly explains the version comparison bug, the code change, its effect on brew outdated, and the added test. It directly matches the changeset.

Recent review info

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Commits

Reviewing files that changed from the base of the PR and between 2ea376f and c503942.

Files selected for processing: 2

• Library/Homebrew/test/version_spec.rb
• Library/Homebrew/version.rb

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[MikeMcQuaid]

Thanks!