[Demo] C416 false positive with sequences as comprehension elements

[tkim602]

Fixes #12

Demo provenance

This live replay reproduces a historical open-source issue and candidate patch, then runs it through the deployed frozen PatchCheck verifier.

• Original issue: C416 false positive with sequences as comprehension elements adamchainz/flake8-comprehensions#198
• Upstream reference fix: Fix false positives in C416 for list comprehensions returning tuples adamchainz/flake8-comprehensions#200
• Original repository: https://github.com/adamchainz/flake8-comprehensions
• Base commit: adamchainz/flake8-comprehensions@16a6405
• Model exposure: FT06 ID evaluation example
• Frozen reference outcome: SAFE
• Candidate patch SHA-256: 1352f9be1aef608917258115d92eeb8856df5b8a938b26c57b0bad9742037501

GitHub canonicalizes unchanged hunk context when rendering the pull request diff; the base file and candidate code edit are reproduced exactly.

Selection was fixed in docs/demo-cases.json before inference. PatchCheck is advisory and does not merge or approve this patch.

[github-actions]

PatchCheck review

Model signal: LOWER
Model risk percentile: 28.2

Code-change findings

• medium: production Python changed without test-file changes (src/flake8_comprehensions.py)

Fingerprints

• base_sha: 766ec5ea4637a3d56d9fc1dd7c9bbfbe4c61b7d7
• head_sha: 5b40126225eb6324c202b3238727362529825637

Review-priority signal only; not a safety approval.