Aos QA

/aos-qa

Select test files or name the feature to audit, then run /aos-qa.

For targeted reviews: /aos-qa unit · /aos-qa integration · /aos-qa e2e · /aos-qa coverage · /aos-qa contracts

What gets checked

Test pyramid

• Unit tests are the majority (≥ 60% of test count) — fast and isolated
• Integration tests verify service + real database interaction
• E2E tests cover critical user journeys only — not implementation details
• No inverted pyramid (few units, many e2e — slow, brittle, expensive)

Test naming and structure

• Names describe behaviour: should throw when email is taken — not test 1 or works correctly
• Arrange–Act–Assert structure with blank lines separating each phase
• One logical assertion per test (multiple expect calls allowed when testing one outcome)
• Test file lives alongside the module it tests (user.service.spec.ts next to user.service.ts)

Test isolation

• Tests pass in any order — no shared mutable state between tests
• Each test sets up and tears down its own data
• beforeEach used for fixture setup — not shared mutation across tests
• No setTimeout or sleep — use fake timers (vi.useFakeTimers) or waitFor

Mocking strategy

• Mocks only at system boundaries: HTTP clients, database, external APIs, file system
• No mocking of internal module methods — that tests implementation, not behaviour
• Mock implementations match the real interface (typed mocks with satisfies)
• Spy assertions check arguments or return values — not just that a function was called

Coverage and completeness

• Happy path covered
• Validation error paths covered (missing fields, wrong types, out-of-range values)
• Authorization error paths covered (unauthenticated, forbidden, wrong owner)
• Not-found cases covered
• Concurrency edge cases covered where relevant (duplicate submission, race conditions)
• Service / business logic layer at ≥ 80% line coverage

Test data

• No hardcoded IDs — use factories or crypto.randomUUID()
• Factories produce valid, complete objects with overridable defaults
• Database tests rolled back or truncated after each test — no leaking data

Snapshot tests

• Snapshot tests used sparingly — only for stable, presentational output
• Snapshots reviewed before committing (not auto-approved)
• Failing snapshots investigated — not blindly updated with --updateSnapshot
• Large inline snapshots extracted to .snap files

Contract tests (API consumers and producers)

• If this service is consumed by other services: consumer-driven contract tests exist (Pact or similar)
• If the API schema changed: contract tests run before deploying to catch consumer breakage
• OpenAPI / GraphQL schema kept in sync with implementation

Performance baselines

• Critical endpoints have response-time assertions or load test baselines
• Database-heavy tests run against realistic data volumes — not 3 rows

Output format

[FAIL] Isolation — shared mutable users array modified across tests
File: src/users/user.service.spec.ts:15
Fix: move users array into beforeEach so each test gets a fresh copy

[FAIL] Snapshot — large inline snapshot auto-approved without review
File: src/components/__tests__/ProductCard.spec.ts:44
Fix: review the snapshot diff; if the change is intentional, commit the .snap file after inspection

[WARN] Coverage — no test for duplicate email case in UserService.create()
File: src/users/user.service.ts:34
Fix: add: it('should throw ConflictError when email is already registered')

[WARN] Mocking — UserService.sendWelcomeEmail() mocked internally
File: src/users/user.service.spec.ts:22
Fix: inject EmailService as a dependency and mock at the boundary instead

Summary: 2 FAIL · 2 WARN · 13 PASS

Full reference

See REFERENCE.md for the test pyramid diagram, factory patterns, and contract testing setup.