generate-cask-ci-matrix: respect maximum_macos requirement

[p-linnane]

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[Copilot]

Pull request overview

This PR updates the generate-cask-ci-matrix dev command to respect cask depends_on maximum_macos constraints when selecting GitHub Actions macOS runners, ensuring CI jobs aren’t generated for macOS versions the cask declares unsupported.

Changes:

• Update runner filtering to apply both minimum (depends_on macos:) and maximum (depends_on maximum_macos:) macOS requirements when selecting macOS runners.
• Add specs covering minimum macOS, maximum macOS, and the “no runners satisfy maximum” case (macOS is skipped rather than testing all macOS runners).

Reviewed changes

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

File	Description
Library/Homebrew/dev-cmd/generate-cask-ci-matrix.rb	Applies maximum_macos (and minimum macOS) constraints when filtering macOS CI runners.
Library/Homebrew/test/dev-cmd/generate-cask-ci-matrix_spec.rb	Adds unit tests asserting runner selection respects min/max macOS requirements and skips macOS when none match.

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[github-code-quality]

Code Coverage Overview

Languages: Ruby

Ruby / code-coverage/simplecov

The overall coverage in the cask-ci-matrix-maxim... branch is 74%. The coverage in the main branch is 78%.

Show a code coverage summary of the most impacted files.

File	main c6a08de	cask-ci-matrix-maxim... b854d5f	+/-
cask/info.rb	96%	0%	-96%
cask/installer.rb	91%	28%	-63%
cask/artifact/a...ct_uninstall.rb	89%	32%	-57%
cask/audit.rb	63%	25%	-38%
cask/cask_loader.rb	96%	65%	-31%
bundle/extensions/flatpak.rb	37%	94%	+57%
extend/os/linux/diagnostic.rb	0%	67%	+67%
os/linux/elf.rb	0%	84%	+84%
extend/os/linux/sandbox.rb	0%	95%	+95%
extend/os/linux...ystem_config.rb	0%	99%	+99%

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_{Updated June 06, 2026 01:09 UTC
Code Coverage is in Public Preview. Learn more and provide us with your feedback.}

[MikeMcQuaid]

Thanks!