user-system/docs/evidence/ops/2026-03-28/quality/COVERAGE_REMEDIATION_20260328-102456.md

2026-03-28 Q-004 Coverage Remediation Pass 12

Scope

• Continue strict Q-004 closure work after Pass 11.
• Fully close the remaining low-coverage frontend/admin/src/lib/http/client.ts module before moving to the next task.
• Re-verify closure through targeted tests plus full frontend validation.

Changes

Frontend

• Extended module coverage in:
  • frontend/admin/src/lib/http/client.test.ts
• Newly covered behavior includes:
  • business-error refresh rejection and session cleanup
  • request retry during an already in-flight refresh
  • failed shared-refresh retry when no access token remains
  • caller-provided AbortSignal propagation
  • download retry path that still ends in 401
• Hardened refresh hygiene in:
  • frontend/admin/src/lib/http/client.ts
• Production code change:
  • the cached shared refresh promise is now stored as a non-rejecting waiter promise
  • this keeps concurrent waiters working while avoiding an unhandled rejected promise when refresh fails

Backend

• No backend code changes were required in this pass.

Verified Commands

cd D:\project\frontend\admin
npm.cmd run test:run -- src/lib/http/client.test.ts
npm.cmd run lint
npm.cmd run build
npm.cmd run test:coverage

Results

Frontend coverage

• Overall:
  • statements 83.86%
  • branches 72.68%
  • functions 79.87%
  • lines 84.72%
• Target areas:
  • src/lib/http/client.ts: statements 100%, branches 92.30%, functions 100%, lines 100%
  • src/lib/http/csrf.ts: statements 100%, branches 88.46%, functions 100%, lines 100%
  • src/pages/admin/ProfileSecurityPage/ProfileSecurityPage.tsx: statements 70.17%, branches 48.97%, functions 67.92%, lines 70.40%

Validation Notes

• Frontend full coverage now completes with 42 passing test files and 193 passing tests.
• The required sequential frontend validation path passed:
  • test:run -- src/lib/http/client.test.ts
  • lint
  • build
  • test:coverage
• The successful frontend coverage run still emits one post-summary jsdom AggregateError network-noise line.
  • It does not fail the command.
  • It remains a real validation-hygiene issue and should continue to be tracked honestly.

Real Conclusion

• src/lib/http/client.ts is no longer an open Q-004 gap.
• The lib/http hotspot is now closure-grade for the targeted modules covered in this pass.
• Q-004 still cannot be honestly declared closed.
• The remaining highest-value frontend gap is now more concentrated in:
  • deeper remaining ProfileSecurityPage branches
  • the post-summary jsdom AggregateError coverage-noise hygiene issue