test(pr-to-video): pin the code-vocabulary section of the frame packet

[jrusso1020]

What

Three test cases in skills/pr-to-video/scripts/workflow-guardrails.test.mjs covering the code-vocabulary half of this skill's frame-packet delta, plus the skills-manifest.json regeneration that goes with a changed skill.

Why

skills/pr-to-video/scripts/frame-packets.mjs is a thin wrapper over the shared packet builder, and its header names the two reasons it exists:

this file pins this workflow's paths plus its two behavioral differences: a code frame must carry an upstream-selected ### Source excerpt, and code frames get a code-vocabulary excerpt appended to their packet.

The first difference is pinned — "code frames without an upstream-selected excerpt fail before dispatch" covers it. The second had no test anywhere in the repo. I confirmed that rather than assuming it: replacing the body of codeVocabularySection with return "", which deletes the feature outright, left all 455 skills tests green.

That matters because the appended section is what tells a frame worker which registry block to install and what its inputs are. The worker never opens code-vocabulary.md itself, so if the section silently stopped being emitted, the symptom would be workers hand-building code motion instead of installing the purpose-built block — a quality regression with no red check anywhere.

One existing assertion touches this code path (assert.doesNotMatch(codePacket, /code-scroll/) on the #1092 packet test), but it pins the narrowing only. It passes trivially when the section is empty, so it cannot detect deletion.

How

The cases live beside the existing frame-packets tests in workflow-guardrails.test.mjs rather than in a new frame-packets.test.mjs, so this skill keeps one test home per module. (Both sibling skills use the frame-packets.test.mjs name, but their wrappers carry no delta — this skill put its packet tests in the guardrails file first, and splitting them across two files now would be worse than the naming asymmetry.)

• a code frame carries the vocabulary excerpt for the block it names — a focal: code-diff frame's packet gets the ## Code block excerpt (code-diff) section and the block's own vocabulary line.
• a code block the vocabulary does not describe still names itself for install — an unrecognized code-* id falls back to Use registry block \`.` rather than emitting nothing, so the worker still learns what to install.
• a mechanism frame gets no code-block section at all — a non-code focal appends nothing.

Assertions are on the section's structure and the block id, not on the vocabulary's prose, so rewording code-vocabulary.md will not break them.

The code-vocabulary.md-missing branch inside codeVocabularySection is deliberately not covered: SKILL_DIR is resolved from import.meta.url, so that branch is only reachable by deleting a checked-in file.

Test plan

• node --test on the full CI-discovered skills set: 458 pass, 0 fail (455 before, +3 here).

• Sensitivity checked, not just presence: with codeVocabularySection neutered to return "", the two positive cases fail and the seven pre-existing tests in the file stay green. Reverted before committing.

• bun scripts/lint-skills.ts clean (31 skill files), node scripts/check-skill-mirror.mjs clean (24 files byte-identical).

• bun packages/cli/scripts/gen-skills-manifest.ts --check reported pr-to-video out of date, regenerated, re-checked in sync (19 skills).

• oxfmt --check clean on the edited file.

• Unit tests added/updated

• Manual testing performed

• Documentation updated (if applicable)

— Rames Jusso

[miguel-heygen]

Substantive notes for the approval above:

Focused review of both changed files and the owning codeVocabularySection production path.

Strengths

• skills/pr-to-video/scripts/workflow-guardrails.test.mjs:148 pins the named-block excerpt boundary and block identity without coupling to mutable vocabulary prose.
• skills/pr-to-video/scripts/workflow-guardrails.test.mjs:163 separately pins the unknown-code-* fallback instruction, while :179 proves non-code mechanism frames receive no code-block section.
• skills-manifest.json:61 is the only generated delta, and the manifest, skill lint, and mirror checks all reproduce cleanly.

Independent verification

• Focused file: 11/11 pass; full discovered skill suite: 168 pass, 0 fail.
• Mutation check: replacing the complete helper body with return "" makes exactly the two positive pins fail while the mechanism negative remains green.
• The untested missing-code-vocabulary.md precondition is acceptable: its observable output is the same fallback pinned by the unknown-block case, and the checked-in reference is protected by manifest/package validation.
• Exact head 56c24ba543686ab254799e48a2dd9d3a0b227c17 is terminal green; BLOCKED was reviewer-gate only.

Verdict: APPROVE
Reasoning: The tests close a measured regression gap, are mutation-sensitive, avoid brittle prose assertions, and introduce no production behavior change.

— Magi