Regression Sweep

Core rule

A bug rarely lives alone when it comes from a shared changed boundary. After the direct regression turns green, search for sibling paths with the same pattern.

Sweep

1. Name the underlying failure class, not only the symptom.
2. Search callers, copies, provider variants, serializers, docs snippets, tests, and generated artifacts for the same construct.
3. Add a regression test that fails when the causal defect returns.
4. Test adjacent inputs: empty, multiple values, spaces/Unicode, old/new versions, absent dependencies, and reruns.
5. Re-run the broad gate after sibling fixes.

Examples: one ANSI-decoding read implies searching every PowerShell read-modify-write; one stale version string implies checking every declared version surface; one bad subprocess argument shape implies checking all sibling child-process calls.

Do not “fix everything similar” blindly—confirm the shared cause before editing.