# Caliber Testing

Writes Vitest tests following project patterns: __tests__/ directories, vi.mock() for...

- Repository: https://github.com/caliber-ai-org/ai-setup (1310 stars)
- Category: Testing
- License: MIT
- Last updated: 2026-09-24
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add caliber-ai-org/ai-setup --skill caliber-testing -g -a claude-code -y`
Codex: `npx skills add caliber-ai-org/ai-setup --skill caliber-testing -g -a codex -y`
Cursor: `npx skills add caliber-ai-org/ai-setup --skill caliber-testing -g -a cursor -y`
Gemini CLI: `npx skills add caliber-ai-org/ai-setup --skill caliber-testing -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add caliber-ai-org/ai-setup`

## Description

Writes Vitest tests following project patterns: __tests__/ directories, vi.mock() for module mocking with vi.hoisted() for test-time factories, global LLM mock from src/test/setup.ts, environment variable save/restore in beforeEach/afterEach, vi.clearAllMocks() lifecycle, and test file organization. Use when user says 'write tests', 'add test coverage', 'test this', creates *.test.ts files, or when test failures appear in CI. Do NOT use for non-test code or for debugging without writing tests.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Caliber Testing

## Critical

- All test files MUST be placed in `__tests__/` directories parallel to source files: `src/[module]/__tests__/[module].test.ts`
- Register any new `__tests__/` directories in `vitest.config.ts`'s `include` glob (already configured: `src/**/*.test.ts`)
- NEVER mock `src/test/setup.ts`, it is the global LLM provider mock already applied to all tests
- Environment variable tests MUST save `process.env` in `beforeEach`, restore in `afterEach`, and explicitly delete env vars to test absence
- Temporary file/directory cleanup MUST happen in `afterEach`, not in individual test cleanup. Use `fs.rmSync(dir, { recursive: true, force: true })`
- When a test requires unmocking modules mocked in global setup, call `vi.unmock('../module.js')` BEFORE the import statement
- Run `pnpm test` locally and `pnpm test:coverage` before committing to verify coverage thresholds (lines: 50, functions: 50, branches: 50, statements: 50)

## Instructions

### Step 1: Create the test file in the correct directory
Create `src/[module]/__tests__/[module].test.ts`. The parent source file is `src/[module]/[module].ts`.

**Verify**: The `__tests__` directory exists at the same level as the source file being tested.

### Step 2: Import test framework
At the top of every test file, import from `vitest`:
```typescript
import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
```

Add additional imports based on what you're testing:
- File system: `import fs from 'fs'; import path from 'path'; import os from 'os';`
- Temporary files: Use `fs.mkdtempSync(path.join(os.tmpdir(), 'caliber-prefix-'))`
- Exec: `import { execSync } from 'child_process';`

**Verify**: All required test utilities are imported before test definitions.

### Step 3: Set up module mocking (if needed)
If testing a module that imports other modules you want to mock:

```typescript
vi.mock('../config.js', () => ({
  loadConfig: vi.fn(),
  writeConfigFile: vi.fn(),
}));
```

The rest: https://github.com/caliber-ai-org/ai-setup/blob/HEAD/.agents/skills/caliber-testing/SKILL.md