Style.check_style_and_print and Style.check_style_json take **options as T.untyped and forward it blind, so a caller's mistyped keyword reaches check_style_impl as a runtime ArgumentError instead of failing brew typecheck. Give both explicit keyword arguments instead.

display_cop_names goes with the splat: it was threaded through four signatures and never read, since run_rubocop never passes --display-cop-names to RuboCop, which displays cop names by default.

brew style now states outright that --only-cops excludes no cops, rather than leaving that to run_rubocop testing except_cops before only_cops.

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• [ ] For bug fixes, have you given step-by-step brew commands to reproduce the bug?


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• [x] 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.

Claude Code with Opus 5, with local review and testing.