qa-refactoring

📁 vasilyu1983/ai-agents-public 📅 Jan 23, 2026
27
总安装量
27
周安装量
#7577
全站排名
安装命令
npx skills add https://github.com/vasilyu1983/ai-agents-public --skill qa-refactoring

Agent 安装分布

claude-code 19
cursor 16
opencode 15
antigravity 14
codex 13

Skill 文档

QA Refactoring Safety

Use this skill to refactor safely: preserve behavior, reduce risk, and keep CI green while improving maintainability and delivery speed.

Defaults: baseline first, smallest safe step next, and proof via tests/contracts/observability instead of intuition.

Quick Start (10 Minutes)

  • Confirm baseline: main green; reproduce the behavior you must preserve.
  • Choose a boundary: API surface, module boundary, DB boundary, or request handler.
  • Add a safety net: characterization/contract/integration tests at that boundary.
  • Refactor in micro-steps: one behavior-preserving change per commit/PR chunk.
  • Prove: run the smallest relevant suite locally, then full CI; keep failures deterministic.

Core QA (Default)

Safe Refactor Loop (Behavior First)

  • Establish baseline: get main green; reproduce the behavior you must preserve.
  • Define invariants: inputs/outputs, error modes, permissions, data shape, performance budgets.
  • Add a safety net: write characterization/contract/integration tests around the boundary you will touch.
  • Create seams: introduce injection points/adapters to isolate side effects and external dependencies.
  • Refactor in micro-steps: one behavior-preserving change at a time; keep diffs reviewable.
  • Prove: run the smallest relevant suite locally, then full CI; keep failures debuggable and deterministic.
  • Ship safely: use canary/dark launch/feature flags when refactors touch production-critical paths.

Risk Levels (Choose Safety Net)

Risk Examples Minimum required safety net
Low rename, extract method, formatting-only unit tests + lint/type checks
Medium moving logic across modules, dependency inversion unit + integration/contract tests at boundary
High auth/permission paths, concurrency, migrations, money/data-loss paths integration + contract tests, observability checks, canary + rollback plan

Test Strategy for Refactors

  • Prefer contract and integration tests around boundaries to preserve behavior.
  • Use snapshots/golden masters only when outputs are stable and reviewed (avoid “approve everything” loops).
  • For invariants, consider property-based tests or table-driven cases (inputs, edge cases, error modes).
  • Avoid making E2E/UI tests the primary safety net for refactors; keep most safety below the UI.
  • For flaky areas: fix determinism first (seeds, time, ordering, network) before trusting results.

CI Economics and Debugging Ergonomics

  • Keep refactor PRs small and reviewable; avoid refactor + feature in one PR.
  • Require failure artifacts for tests guarding refactors (logs, trace IDs, deterministic seeds, repro steps).
  • Reduce diff noise: isolate formatting-only changes (or apply formatting repo-wide once with buy-in).
  • Keep git bisect viable: avoid mixed “mechanical + semantic” changes unless necessary.

Do / Avoid

Do:

  • Add missing tests before refactoring high-risk areas.
  • Add guardrails (linters, type checks, contract checks, static analysis/security checks) so refactors don’t silently break interfaces.
  • Prefer “branch by abstraction” / adapters when you need to swap implementations safely.

Avoid:

  • Combining large structural refactors with behavior changes.
  • Using flaky E2E as the primary safety net for refactors.

Quick Reference

Task Tool/Pattern Command/Approach When to Use
Long method (>50 lines) Extract Method Split into smaller functions Single method does too much
Large class (>300 lines) Split Class Create focused single-responsibility classes God object doing too much
Duplicated code Extract Function/Class DRY principle Same logic in multiple places
Complex conditionals Replace Conditional with Polymorphism Use inheritance/strategy pattern Switch statements on type
Long parameter list Introduce Parameter Object Create DTO/config object Functions with >3 parameters
Legacy code modernization Characterization Tests + Strangler Fig Write tests first, migrate incrementally No tests, old codebase
Automated quality gates ESLint, SonarQube, Prettier npm run lint, CI/CD pipeline Prevent quality regression
Technical debt tracking SonarQube, CodeClimate Track trends + hotspots Prioritize refactoring work

Decision Tree: Refactoring Strategy

Code issue: [Refactoring Scenario]
    ├─ Code Smells Detected?
    │   ├─ Duplicated code? → Extract method/function
    │   ├─ Long method (>50 lines)? → Extract smaller methods
    │   ├─ Large class (>300 lines)? → Split into focused classes
    │   ├─ Long parameter list? → Parameter object
    │   └─ Feature envy? → Move method closer to data
    │
    ├─ Legacy Code (No Tests)?
    │   ├─ High risk? → Write characterization tests first
    │   ├─ Large rewrite needed? → Strangler Fig (incremental migration)
    │   ├─ Unknown behavior? → Characterization tests + small refactors
    │   └─ Production system? → Canary deployments + monitoring
    │
    ├─ Quality Standards?
    │   ├─ New project? → Setup linter + formatter + quality gates
    │   ├─ Existing project? → Add pre-commit hooks + CI checks
    │   ├─ Complexity issues? → Set cyclomatic complexity limits (<10)
    │   └─ Technical debt? → Track in register, 20% sprint capacity

Related Skills

Operational Deep Dives

Shared Foundation

Skill-Specific

See references/operational-patterns.md for detailed refactoring catalogs, automated quality gates, technical debt playbooks, and legacy modernization steps.

Templates

Use copy-paste templates in assets/ for checklists and quality-gate configs:

Resources

Use deep-dive guides in references/ (load only what you need):

Optional: AI / Automation

Do:

  • Use AI to propose mechanical refactors (rename/extract/move) only when you can prove behavior preservation via tests and contracts.
  • Use AI to summarize diffs and risk hotspots; verify by running targeted characterization tests.
  • Prefer tool-assisted refactors (IDE/compiler-aware, codemods) over freeform text edits when available.

Avoid:

  • Accepting refactors that change behavior without an explicit requirement and regression tests.
  • Letting AI “fix tests” by weakening assertions to make CI green.

See data/sources.json for curated external references.