cxc-dev-testing

# Testing & QA Balance: ~40% Backend/API, ~40% Frontend/E2E (Playwright), ~20% Cross-cutting (CI, Security, TDD, Coverage) -- directional guidance, not a hard ratio. **Scope**: test harnesses, fixtures, mock policy, runners, Playwright, CI gates, coverage. Root-cause analysis and debugging playbooks → `dev-debugging`. - This skill owns test adequacy; `dev-code-reviewer` owns finding severity and review process. - CI pipeline ownership and deployment verification: see `dev-devops`. - Data pipeline testing and ETL validation: see `dev-data`. - Design direction context for rendered verification: see `dev-uiux-design`. This skill activates by change-surface when work needs verification depth, regression coverage, or a reproducible test harness. Class, fast path, rule authority, proof, and safety: [dev](../dev/SKILL.md). Current/public evidence: [dev routing](../dev/SKILL.md#conditional-routes). ### 1.3 Risk-First Priorities 1. auth / session / permission boundaries 2. money movement, quota, credits 3. data mutation and irreversible actions 4. file upload / parsing / external webhooks 5. shared API contracts used by frontend clients 6. error paths, retries, rollback behavior ### 1.4 Harness Selector | Problem | Primary Harness | Avoid | |---------|-----------------|-------| | pure business rule | unit / service test | browser test | | route + middleware + serialization | API integration test | mocking the route itself | | DB query / migration / transaction | real DB integration test | fake repository for SQL correctness | | frontend consuming backend JSON | contract test | manual-only verification | | rendered critical flow | Playwright smoke | asserting internal React state | Test-oracle rules apply before accepting green: [oracle integrity](references/test-oracle-integrity.md). ## Modular References | Condition | Reference | |---|---| | Choose verification depth or test a CRUD slice | [core/crud-test-matrix.md](references/core/crud-test-matrix.md) | | Choose model, distribution, fixture policy, or general test rules | [test-strategy.md](references/test-strategy.md) | | New feature unit/service/integration tests (not regression/contract) | [edge-first-testing.md](references/edge-first-testing.md) | | Property/invariant-heavy or mutation testing | [property-and-mutation-testing.md](references/property-and-mutation-testing.md) | | Backend/API, database, or contract verification | [api-test-patterns.md](references/api-test-patterns.md); [backend-testing.md](references/backend-testing.md) | | Rendered browser tests or exploratory browser QA | [browser-testing.md](references/browser-testing.md) | | CI test stages, failures, or flakes | [ci-integration.md](references/ci-integration.md); [ci-pipeline.md](references/ci-pipeline.md) | | ENFORCE_TDD, AI regressions, or test-induced production guards | [tdd-and-regressions.md](references/tdd-and-regressions.md) | | Accessibility, trace/log verification, security, coverage, or pre-flight | [acceptance-gates.md](references/acceptance-gates.md) | | Write acceptance criteria | [acceptance-row-reachability.md](references/acceptance-row-reachability.md) | | Test expectations, prose seams, override/default/fallback fixtures | [test-oracle-integrity.md](references/test-oracle-integrity.md) | | Implementation completion with test/config changes | [patch-integrity.md](references/patch-integrity.md) | | Scarce, paid, rate-limited, or opaque evaluators | [limited-oracle-evaluation.md](references/limited-oracle-evaluation.md) | | Performance/load or C3+ production readiness | [load-testing.md](references/load-testing.md) | | ML/LLM evaluation or quality gates | [ml-evaluation.md](references/ml-evaluation.md) | | Desktop suites and CI matrix | [Native desktop acceptance](../dev-devops/references/native-desktop-acceptance.md) |