testing

# Testing Skill

**Bonded to:** `testing-security-agent` (Secondary)

---

## Quick Start

```bash
# Invoke testing skill
"Write unit tests for my user service"
"Set up integration tests with database"
"Configure load testing with k6"
```

---

## Testing Pyramid

```
            /\
           /E2E\       Few, slow, expensive
          /────\
         /Integration\  Some, medium speed
        /────────────\
       /  Unit Tests  \ Many, fast, cheap
      /────────────────\
```

| Type | Coverage | Speed | Cost |
|------|----------|-------|------|
| Unit | 80%+ | Fast | Low |
| Integration | 60%+ | Medium | Medium |
| E2E | Critical paths | Slow | High |

---

## Examples

### Unit Test (pytest)
```python
import pytest
from unittest.mock import Mock
from app.services.user_service import UserService

class TestUserService:
    @pytest.fixture
    def service(self):
        return UserService(db=Mock())

    def test_get_user_returns_user(self, service):
        service.db.get_user.return_value = {"id": 1, "name": "John"}

        result = service.get_user(1)

        assert result["name"] == "John"
        service.db.get_user.assert_called_once_with(1)

    def test_get_user_raises_when_not_found(self, service):
        service.db.get_user.return_value = None

        with pytest.raises(UserNotFoundError):
            service.get_user(999)
```

### Integration Test
```python
import pytest
from fastapi.testclient import TestClient
from app.main import app
from app.database import get_db

@pytest.fixture
def client(test_db):
    def override_get_db():
        return test_db
    app.dependency_overrides[get_db] = override_get_db
    with TestClient(app) as c:
        yield c

def test_create_and_get_user(client):
    # Create user
    response = client.post("/users", json={"email": "test@example.com"})
    assert response.status_code == 201
    user_id = response.json()["id"]

    # Get user
    response = client.get(f"/users/{user_id}")
    assert response.status_code =