# Backend Tests

## Framework

pytest + FastAPI `TestClient` (sync, in-process). No database mocking needed — tests hit real endpoints with real data files.

## Structure

- `conftest.py` — shared fixtures (`client`, `auth_headers`, test data)
- `test_api.py` — endpoint integration tests, organized by router class
- `test_auth.py` — authentication flow tests
- `test_error_handling.py` — edge cases, error responses
- `test_utils.py` — pure utility function tests

## Patterns

- Tests organized in classes: `class TestRiskEndpoints:`
- One test method per scenario: `test_current_risk_map()`, `test_risk_map_with_date()`
- Fixture naming: `client: TestClient`, `auth_headers: dict`
- Assert response status, then JSON structure, then field types/values

```python
class TestSomeRouter:
    def test_something(self, client: TestClient):
        resp = client.get("/api/some/endpoint")
        assert resp.status_code == 200
        data = resp.json()
        assert "key" in data
        assert isinstance(data["key"], list)
```

## Running

```bash
cd backend
source venv/bin/activate
pytest tests/ -v
pytest tests/test_api.py -v -k "test_risk"
```

## Anti-Patterns

- Don't mock endpoints you can test with real data
- Don't hardcode test dates that will go stale
- Don't skip assertions on response structure just because status is 200
- Don't share mutable state between test classes — use fixtures