test(responses): mint the surviving blob as a valid Fernet token

[lidge-jun]

Summary

• dev is red at 12cb129d42: sanitizeEncryptedContentInPlace > plaintext parked in encrypted slots becomes input_text; real blobs survive fails on Linux shard 2/4 and macOS shard 2/2 with Expected: 2, Received: 3.
• fix(responses): reject Fernet-shaped agent plaintext #5239 replaced looksLikeBackendCiphertext with isStructurallyValidFernetToken, which requires canonical base64url, length >= 100, a 0x80 version byte and a 16-byte-aligned ciphertext. The case's stand-in blob "gAAAAAB".padEnd(120, "Qw1_-=") embeds = mid-token, so it is no longer a valid token and is now lowered to input_text as a third rewrite.
• The case asserts that real backend blobs survive untouched. This restores that meaning by minting the blob with the fernetFixture() helper already defined in the same describe, which is the shape the sibling cases added by fix(responses): reject Fernet-shaped agent plaintext #5239 use. The rewrite count returns to 2 and outParts[0] stays byte-identical.
• No production behavior changes; the stricter classifier from fix(responses): reject Fernet-shaped agent plaintext #5239 is kept exactly as merged.

Verification

• Static source analysis against src/server/responses/encrypted-payload.ts: fernetFixture() produces a 73-byte payload with raw[0] = 0x80, encoding to a 100-character canonical base64url token, so isStructurallyValidFernetToken accepts it (decoded.length - 57 === 16).
• Local suites, typecheck and builds were not run in this lane; exact-head hosted CI on this pull request is the execution evidence.

Checklist

• Scope stays focused and avoids unrelated cleanup.
• Docs or release notes were updated when needed.
• Security-sensitive changes were reviewed for secrets, auth, and unsafe defaults.

Summary by CodeRabbit

• Tests
  • Updated encrypted-content sanitization testing to use a valid generated encryption fixture, improving test reliability.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-20T03:30:52.561746Z	3f051a7	PR opened

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ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Repository: lidge-jun/opencodex/.coderabbit.yaml

Review profile: ASSERTIVE

Plan: Advanced

Run ID: 4e850551-03df-4834-94e0-42d108eef3f1

📥 Commits

Reviewing files that changed from the base of the PR and between 12cb129 and 3f051a7.

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• tests/codex-integration/multi-agent-compat.test.ts

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📝 Walkthrough

Walkthrough

The encrypted-content sanitization test now uses a valid encrypted blob from fernetFixture() instead of a hardcoded padded string.

Changes

Encrypted fixture validation

Layer / File(s)	Summary
Use generated Fernet fixture tests/codex-integration/multi-agent-compat.test.ts:1380	The test replaces the hardcoded encrypted blob with the Fernet value returned by fernetFixture(). This keeps the test input tied to the fixture generator.

Priority: ⬇️ Low

Estimated code review effort: 1 (Trivial) | ~3 minutes

Change: Other

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: replacing the invalid surviving encrypted blob with a valid Fernet token in the response test fixture.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 1…
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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