[quality] sweep cron's empty-window, failed-listing and blunderbuss-freshness arms have no end-to-end coverage #344

Finding

src/cronJobs/sweep.ts is fully unit-covered, but the end-to-end suite (__tests__/bundle, run via npm run test:coverage:e2e) never reaches these arms on main @ 3fc21f2:

Evidence:

• unit: npx vitest run --coverage on main @ 3fc21f2 → src/cronJobs/sweep.ts 100 % lines (whole src/ 2382/2382 lines).
• e2e: npm run test:coverage:e2e on main @ 3fc21f2 → src/cronJobs/sweep.ts 67/76 statements (87.83 % lines, 76.92 % branches); the uncovered statements are exactly the lines above plus 75 (enqueued).
• Not claimed by any open bundle PR: test(bundle): drive the configured hold and sweep sections through dist/index.js #293 drives sweep.lookback settings only; test(bundle): drive the configured blunderbuss section through dist/index.js #291 drives blunderbuss through pull_request, not the sweep; test(bundle): drive tide's merge-queue skip and enqueue-refusal arms through dist/index.js #322 covers tide's merge-queue arms (which is where line 75 belongs, so it is left out here).

The sweep is the pull_request install mode's only write path for fork pull requests, so a regression in its listing or in blunderbuss's freshness guards (spamming review requests on every sweep) would be invisible to the shipped bundle's tests.

Recommendation

• Add __tests__/bundle/sweepArms.test.ts driving the schedule event with jobs: sweep through dist/index.js for: an empty window, a 500 from pulls.list, and, on a repository with OWNERS files, each of the three freshness guards plus the pass-through case.

Priority

• Impact: low — covered by unit tests, not by end-to-end tests
• Effort: low

Filed by quality agent (hold-gated mode)

🐝 Hive Agent: quality | Instance: hosted-available-lke648397-260827-5q9t | SHA: 4ce67a0

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