[quality] handlePullReq's jobs-input error arms are never exercised end-to-end through dist/index.js #309

Finding

src/pullReq/handlePullReq.ts runs the jobs input after the registered pull-request handlers. Three of its arms are reached by no __tests__/bundle suite, so the shipped bundle's behaviour on them is unmeasured:

• lines 62-66: the lgtm job's catch (an onPrLgtm failure is returned as a value) and the default arm (could not execute <job>. May not be supported)
• lines 75-80: the TypeError: error handling pull request: … rethrow and the core.setFailed that ends the run
• src/pullReq/onPrLgtm.ts line 30: could not get labels from issue when the labels read fails

Evidence

• Unit: npx vitest run --coverage on main @ 3fc21f2 — handlePullReq.ts 100 / 100 / 100 / 100, onPrLgtm.ts 100 / 100 / 100 / 100 (__tests__/pullReqTest/handlePullReq.test.ts, onPrLgtm.test.ts).
• End-to-end: npm run test:coverage:e2e on main @ 3fc21f2 (Node v26.10.0, vitest 5.0.3, local run 2026-10-04) — handlePullReq.ts 80.76 % lines, uncovered 46,62-66,75-80; onPrLgtm.ts 83.33 % lines, uncovered 19,30.

Covered by unit tests but not end-to-end → medium.

Line 46 (jobs empty and no registered handlers) and onPrLgtm.ts line 19 (a pull_request payload without pull_request.number) are not reachable from a real pull_request event and are out of scope.

Recommendation

• __tests__/bundle/pullReqJobsArms.test.ts: a pull_request synchronize run with an unsupported jobs entry fails naming the job after the handlers have run; one whose lgtm job's GET /issues/1 answers 500 fails with could not get labels from issue and deletes nothing; jobs: lgtm <unsupported> removes the label and still fails the run

Measured with that file: handlePullReq.ts 80.76 → 96.15 % e2e lines (only 46 left), onPrLgtm.ts 83.33 → 91.66 % (only 19 left).

Priority

• Impact: medium
• Effort: low

Filed by quality agent (hold-gated mode)

🐝 Hive Agent: quality | Instance: hosted-available-lke648397-260827-5q9t | SHA: 709cb6c

— hive: agent=quality backend=copilot model=claude-fable-5.1 copilot=1.0.88