Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/recca0120/code-quest/testing-best-practicesnpx skills add recca0120/code-quest --skill testing-best-practicesgit clone --depth 1 https://github.com/recca0120/code-questWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00090 | $0.01061 |
| Opus 5 | $0.00045 | $0.00531 |
| Sonnet 5 | $0.00018 | $0.00212 |
| Haiku 4.5 | $0.00009 | $0.00106 |
Grade A, and why
testing-best-practices scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 94 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Testing Best Practices (Cross-Cutting)
核心原則 / test double 決策 / Fake Component / 測試放置 — 詳見
frontend-testingServer 測試（DB / socket.io server-side）— 詳見vitest-testing (server)TDD 流程 — 詳見tdd-guidelinesSocket + pipeline harness — 詳見fake-summoner-client/fake-summoner-server
Stack
| Package | Version |
|---|---|
| vitest | ^3.2.4 |
| @testing-library/react | ^16.0.0 |
| @testing-library/user-event | ^14.5.2 |
| msw | ^2.x |
| Storybook | ^10.3.5 |
Async Patterns
| Pattern | Use when |
|---|---|
findByRole(...) |
Element appears after async work |
waitFor(() => expect(...)) |
Condition becomes true after re-renders |
waitForElementToBeRemoved(...) |
Loading spinner disappears |
queryByRole(...) |
Assert something is NOT in DOM |
Async 斷言用 findBy* 或 queryBy* + waitFor；getBy* 保留給同步檢查。
Vitest API Cheatsheet
| API | When |
|---|---|
vi.fn() |
Standalone mock function |
vi.spyOn(obj, 'method') |
Watch/override method（.mockRestore() 可用） |
vi.mock('module') |
Hoisted，替換整個 module（最後手段） |
vi.mocked(fn) |
Type-safe 存取 mock methods |
beforeEach(() => vi.clearAllMocks()) |
Reset call counts |
afterEach(() => vi.restoreAllMocks()) |
Restore originals（與 vi.spyOn 搭配） |
Asserting className
專案 cn() 包了 twMerge 自動解決衝突。斷言 className 時：
- ✅ 斷言 semantic token（行為契約）
expect(el.className).toMatch(/\bz-modal\b/); expect(button).toHaveClass('bg-accent'); - ⚠️ 避免斷言精調 utility（易被視覺微調破）
expect(el).toHaveClass('p-4 text-sm w-5'); // 微調 padding 時 fail
Semantic token 作為 behavior assertion 合理；任意 utility 值（p-4、text-sm）是 implementation detail，不斷言。
Vitest vs Storybook Play Function
| Aspect | Vitest + RTL | Storybook Play |
|---|---|---|
| Purpose | Logic / state / integration / errors | Visual states / a11y / interaction demos |
| Environment | jsdom (Node) | Real browser |
| Speed | Fast, CI-first | Slower, visual regression |
Test behavior in Vitest；Storybook 用於 visual snapshot 和 a11y audit。不重複兩邊都寫。
What ships with it
2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 3d ago First seen · 94 lines · 90 tokens per session scan A 37458d5ca93d
testing-best-practices is a skill published in the GitHub repository recca0120/code-quest (11 stars, last pushed 2mo ago), licensed MIT. It adds 90 tokens to every session and 1,061 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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