---
name: cyclone-tests
description: "Cyclone pytest + vitest fixture patterns, prodfiles layout, backend/tests/fixtures/ conventions, .test.tsx sibling rule. Use when: adding a backend pytest case, adding a frontend vitest test, or wiring in a real-EDI prodfiles sample."
---

# cyclone-tests

The Cyclone test suite is split two ways: **backend pytest** (89 test files under `backend/tests/`, 13 flat fixtures in `backend/tests/fixtures/`, one autouse `conftest.py` that resets the DB per-test) and **frontend vitest** (59 `*.test.ts(x)` siblings across `src/`, two rendering styles — `@testing-library/react` and a custom `createRoot`+`Probe` shim). This skill codifies the conventions so additions stay consistent with what's already there.

As of this writing: **89 backend test files**, **13 flat backend fixtures**, **59 frontend `*.test.ts(x)` siblings**, and **23 prodfiles samples** across `docs/prodfiles/{837p-from-axiscare,835fromco,FromHPE,claims}/`. The next increment is **SP22**.

## When to use

- **Adding a backend pytest case.** You're about to add a new `test_*.py` under `backend/tests/` and need the autouse DB-fixture rules, the fixture-path convention, and the right naming flavor (`test_api_*.py` vs `test_<module>_*.py`).
- **Adding a frontend vitest test.** You're about to add a `*.test.ts(x)` sibling and need the `// @vitest-environment happy-dom` setup, the act-environment flag, and the right rendering helper (`@testing-library/react` vs the `createRoot`+`Probe` shim).
- **Dropping in a prodfiles fixture.** You have a real EDI sample under `docs/prodfiles/<source>/` and need the copy step that makes it test-runnable without coupling the test to the prodfiles archive.
- **Debugging a flaky test.** A test passes locally but flakes in CI — load this skill to check the determinism + no-network rules before chasing the symptom.

## Conventions

1. **Frontend sibling rule.** Every new file in `src/` that contains testable logic gets a `*.test.ts(x)` next to it. `useFoo.ts` → `useFoo.test.ts`. `ClaimDrawer.tsx` → `ClaimDrawer.test.tsx`. The 59 existing siblings follow this; CI implicitly enforces it via the default `src/**/*.test.ts(x)` glob in `vitest.config.ts`.
2. **Backend test location.** Tests live under `backend/tests/test_*.py`. Two flavors, two naming patterns:
   - **Integration tests** (FastAPI surface) → `test_api_<topic>_<verb>.py` — e.g. `test_api_parse_persists.py`, `test_api_999.py`.
   - **Pure-unit tests** (parsers, validators, store internals) → `test_<module>_<behavior>.py` — e.g. `test_cas_codes.py`, `test_pubsub.py`.
3. **Prodfiles drop-in.** Real EDI samples live under `docs/prodfiles/<source>/<file>.txt` (sources seen so far: `837p-from-axiscare/`, `835fromco/`, `FromHPE/`, `claims/`). To use one in a test: copy the file to `backend/tests/fixtures/<descriptive-name>.txt` (flat — no per-test subdirectories; the existing 13 fixtures all sit at the top level) and reference it from the test as a module-level `Path` constant. See `## Patterns` for the exact line.
4. **Determinism.** Time-sensitive tests must not depend on wall-clock time.
   - **Frontend** uses `vi.useFakeTimers()` + `vi.setSystemTime(new Date("YYYY-MM-DDTHH:MM:SSZ"))` (see `src/components/TailStatusPill.test.tsx:54-58`) and `vi.advanceTimersByTime(ms)` to drive interval / backoff code deterministically.
   - **Backend** dates are passed explicitly as fixture values — e.g. `datetime.now(timezone.utc)` is fine for "now-ish" anchors, but for fixed dates pass `datetime(2026, 6, 20, tzinfo=timezone.utc)`. The project does **not** currently use `freezegun` or `mock.patch(datetime)`; if you need deterministic date mocking, propose adding `freezegun` to `backend/pyproject.toml` rather than rolling your own.
5. **No network.** Tests must not hit the network.
   - **Backend:** `fastapi.testclient.TestClient(app)` runs in-process; no uvicorn. The autouse `conftest.py` fixture (`backend/tests/conftest.py:20`) points `CYCLONE_DB_URL` at `tmp_path/test.db`, calls `db._reset_for_tests()` + `db.init_db()`, and wires a fresh `EventBus` onto `app.state`.
   - **Frontend:** `vi.stubGlobal("fetch", vi.fn().mockResolvedValue(...))` for hooks; `vitest.config.ts` sets `VITE_API_BASE_URL=http://test.local` so the `api` module doesn't throw `notConfiguredError` before the mock fires.
6. **pytest collection.** Run `cd backend && python -m pytest tests/<file>::<name> -v` for the fastest single-test feedback loop. Run `cd backend && python -m pytest tests/<file> -v` for one file. Run `cd backend && python -m pytest` for the full suite — this is the merge gate. Frontend: `npm test` (alias for `vitest run`) for the full suite; `npx vitest run src/hooks/useFoo.test.ts` for one file.

## Patterns

### Backend pytest using a fixture + per-test SQLite DB

Canonical shape — see `backend/tests/test_api_999.py:1-50` for the full file. The autouse `conftest.py` already provides the DB init + `EventBus` reset; most tests just add a `client` fixture.

```python
"""Tests for the FastAPI surface in cyclone.api for the 999 endpoint."""
from __future__ import annotations

from pathlib import Path

import pytest
from fastapi.testclient import TestClient

from cyclone.api import app

# Fixture reference — flat, module-level Path constant. NEVER reach into
# docs/prodfiles/ from a test; the fixtures/ dir is the test-consumed surface.
ACCEPTED = Path(__file__).parent / "fixtures" / "minimal_999.txt"
REJECTED = Path(__file__).parent / "fixtures" / "minimal_999_rejected.txt"


@pytest.fixture
def client() -> TestClient:
    return TestClient(app)


def test_parse_999_endpoint_happy_path(client: TestClient):
    text = ACCEPTED.read_text()
    resp = client.post(
        "/api/parse-999",
        files={"file": ("minimal_999.txt", text, "text/plain")},
        headers={"Accept": "application/json"},
    )
    assert resp.status_code == 200, resp.text
    body = resp.json()
    assert body["ack"]["ack_code"] == "A"
```

Override the autouse DB fixture only when you need a custom env (e.g. a per-test backup directory) — see `backend/tests/test_999_rejected_state.py:20-25`:

```python
@pytest.fixture(autouse=True)
def _setup(tmp_path, monkeypatch):
    monkeypatch.setenv("CYCLONE_DB_URL", f"sqlite:///{tmp_path}/inbox.db")
    from cyclone import db
    db._reset_for_tests()
    db.init_db()
    yield
```

### Frontend vitest `*.test.tsx` for a component using fake timers

Pattern taken from `src/components/TailStatusPill.test.tsx:1-62` — uses `vi.useFakeTimers()` + `vi.setSystemTime(...)` to drive interval-based code deterministically.

```ts
// @vitest-environment happy-dom
// React's act warnings need an act-aware environment — mirror the other
// hook tests in this repo.
(globalThis as { IS_REACT_ACT_ENVIRONMENT?: boolean }).IS_REACT_ACT_ENVIRONMENT = true;

import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
import { MyComponent } from "./MyComponent";

describe("MyComponent", () => {
  beforeEach(() => {
    vi.useFakeTimers();
    vi.setSystemTime(new Date("2026-06-20T12:00:30Z"));
  });

  afterEach(() => {
    vi.useRealTimers();
  });

  it("test_renders_after_interval_tick", () => {
    vi.advanceTimersByTime(30_000);  // drive the setInterval
    // …assert…
  });
});
```

### Frontend vitest `*.test.tsx` for a component using `@testing-library/react` + `happy-dom`

Pattern taken from `src/hooks/useInboxLanes.test.ts:1-80`. (A handful of older tests — `useClaimDetail.test.ts`, `useDrawerUrlState.test.ts`, `TailStatusPill.test.tsx` — roll a custom `createRoot`+`Probe` shim instead. Both styles are accepted; `@testing-library/react` is preferred when the hook has async dependencies because `waitFor` is built in.)

```ts
// @vitest-environment happy-dom
(globalThis as { IS_REACT_ACT_ENVIRONMENT?: boolean }).IS_REACT_ACT_ENVIRONMENT = true;

import { afterEach, describe, expect, it, vi } from "vitest";
import { act, cleanup, renderHook, waitFor } from "@testing-library/react";
import { useMyHook } from "./useMyHook";

vi.mock("@/lib/api", () => ({
  api: { fetchFoo: vi.fn() },
}));

afterEach(() => {
  cleanup();
  vi.unstubAllGlobals();
  vi.useRealTimers();
});

describe("useMyHook", () => {
  it("loads data on mount", async () => {
    vi.stubGlobal("fetch", vi.fn().mockResolvedValue({
      ok: true,
      json: async () => ({ items: [] }),
    }));
    const { result } = renderHook(() => useMyHook());
    await waitFor(() => expect(result.current.loading).toBe(false));
    expect(result.current.items).toEqual([]);
  });
});
```

## Anti-patterns

- **Don't put frontend tests in `src/__tests__/`.** No such directory exists in the codebase — `__tests__` only appears in the SP-catalog plan itself. Use the sibling rule (`useFoo.ts` → `useFoo.test.ts`).
- **Don't reach into `docs/prodfiles/` directly from a test.** Always copy to `backend/tests/fixtures/<name>.txt` first. The prodfiles directory is the source-of-truth archive and may be reorganized; the fixtures directory is the test-consumed surface and is stable.
- **Don't use wall-clock sleeps for timing.** A handful of legacy tests use `await new Promise((r) => setTimeout(r, 200))` (see `src/components/SearchBar.test.tsx:281,323,373` and `src/hooks/useSearch.test.ts:174`) — these are known flaky in CI. Use `vi.useFakeTimers()` + `vi.advanceTimersByTime(ms)` instead, or `waitFor(...)` from `@testing-library/react`.

## Related skills

- **`cyclone-spec`** — every SP-N spec lists test impact; load this when drafting or reviewing the spec to confirm fixture / `.test.tsx` implications for the increment.
- **`cyclone-edi`** — most backend tests cover parser + validator behavior; load when the increment touches an EDI parser or adds a validator rule (R200/R210/NPI Luhn/EIN/CAS).
- **`cyclone-tail`** — most frontend tests cover hook behavior (`useTailStream`, `useMergedTail`); load when the increment changes the wire format or adds a streaming hook.
- **`cyclone-store`** — write-path tests live here; load when the increment touches `store.py`, adds a new entity, or wires a new `<entity>_written` event.
- **`cyclone-api-router`** — endpoint tests live in `backend/tests/test_api_*.py`; load when the increment adds or changes an HTTP endpoint.
- **`cyclone-frontend-page`** — page-component tests live next to pages in `src/pages/*.test.tsx`; load when the increment adds or refactors a page.
- **`cyclone-cli`** — CLI smoke tests live in `backend/tests/test_cli_*.py`; load when the increment adds a CLI subcommand.
- **`superpowers:test-driven-development`** (global) — the upstream TDD workflow. Load first when starting any new feature increment; this skill only codifies the Cyclone-specific test layout on top of TDD.