[p-linnane]

Advisory history reconciliation needs every revision of a formula to load on all four simulated platforms. Obsolete DSL made many older revisions unloadable, and on macOS the Linux legs only loaded revisions using MacOS by reading the host.

In advisory walks, MacOS.version and retired on_system releases now answer from the simulated target, with Linux getting the historical NULL answers. Other callers keep the host MacOS API. Undated deprecate!/disable!, build.include?, bottle prefix, cxxstdlib_check, ScriptFileFormula and StrictSubversionDownloadStrategy also load. Anything else still fails closed.

107 of 112 previously unloadable core revisions now load on all four platforms, on macOS and Linux.

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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.

Claude Code (Opus 5.5) drafted the implementation and tests; I reviewed the diff, verified the new tests fail without the change and pass with it, and ran brew lgtm --online plus targeted specs on macOS and Linux.

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[Copilot]

Copilot review overview

🔵 Needs a closer look

The changes require final human review because they are too complex or risky for automated approval.

Review effort: Lite
Findings: None

What changed in this PR

Updates advisory history loading so legacy formula DSL evaluates against simulated platforms while preserving host behaviour elsewhere.

Changes:

• Adds simulated macOS/Linux historical API handling.
• Supports additional obsolete DSL constructs.
• Updates history and formula-version tests.

File	Description
Library/​Homebrew/​vulns/​history.rb	Updated as part of this pull request.
Library/​Homebrew/​test/​vulns/​history_spec.rb	Updated as part of this pull request.
Library/​Homebrew/​test/​formula_versions_spec.rb	Updated as part of this pull request.
Library/​Homebrew/​test/​dev-cmd/​generate-vulns-advisories_spec.rb	Updated as part of this pull request.
Library/​Homebrew/​formula_versions.rb	Updated as part of this pull request.

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