Menene test fixtures da setup/teardown?

Question

Accepted Answer

**Test fixtures** sune tsarin da aka tsayar (bayanai, abubuwa, yanayin) da gwaje-gwaje ke buƙatar don aiki, kuma **setup/teardown** hanyoyin suna shirya da tsaftace wadannan halin kafin da bayan gwaje-gwaje. Suna rage maimaita da tabbatar da gwaje-gwaje suke aiki a cikin yanayin tsayawa, ware-ware.

## Shirya da tsaftaci

```text
SETUP → runs BEFORE tests to prepare the context (create objects, data, connections)
TEARDOWN → runs AFTER tests to CLEAN UP (close connections, delete data, reset state)
→ frameworks provide hooks:
  beforeEach / afterEach → before/after EACH test (fresh state per test — common)
  beforeAll / afterAll → once before/after ALL tests in a group (shared expensive setup)
```

```js
describe('UserService', () => {
  let service, db;
  beforeEach(() => {                 // fresh setup for EACH test (isolation)
    db = createTestDb();
    service = new UserService(db);
  });
  afterEach(() => db.close());        // clean up after each test

test('creates a user', () => { /* uses the fresh service/db */ });
});
```

## Fixtures — bayanai/yanayin gwaje-gwaje da ake iya amfani da su

```text
FIXTURES → predefined data/objects tests use (a known starting state):
  → e.g. a sample user, a set of records, a configured object
  → FACTORIES → generate test data flexibly (build objects with sensible defaults +
    overrides) — better than hardcoded data for varied scenarios
→ reduce duplication; give tests consistent, known data to work with
```

## Kyakkyawan aiki

```text
✓ Prefer beforeEach (fresh state per test) → ISOLATION (tests don't affect each other)
✓ Clean up in teardown → no leftover state causing flaky/order-dependent tests
✓ Keep setup minimal and clear; use factories for flexible test data
✓ Don't share MUTABLE state across tests (a cause of flakiness/order-dependence)
```

## Me ya sa ya matufi

Ganewa game da test fixtures da setup/teardown yana da daraja saboda sune **mahimmanci don rubuta gwaje-gwaje masu tsatsa, ware-ware, masu tsari**, don haka yana da ilimin fahimtar tattalin arziki.

Gwaje-gwaje suna buƙatar yanayin da aka tsayar a ciki (bayanai, abubuwa, yanayin), kuma **setup/teardown** hanyoyi (haƙƙin `beforeEach`/`afterEach` da `beforeAll`/`afterAll` da frameworks ke bayarwa) suna shirya wadannan halin kafin gwaje-gwaje da tsaftace su bayan — rage maimaita (shirya da aka gida a gida shimfiɗa bakwai maimakin a gwaje-gwaje kowane) da tabbatar da gwaje-gwaje suke aiki a cikin yanayin da aka sani.

Ganewa game da waɗannan haƙƙin da yaushe ake amfani da kowannen (beforeEach don saɓon yanayin kowane gwaje-gwaje, beforeAll don shirya mai tsada da aka damje) ya zama dole don tsarawa gwaje-gwaje sosai.

Ganewa game da **fixtures** (bayanai da abubuwan gwaje-gwaje da aka tsara da aka ba da gwaje-gwaje yanayin da aka sani) da **factories** (samar da bayanai gwaje-gwaje da karewa tare da kyakkyawan abubuwa aiki da bincike, mafi kyau fiye da bayanai da aka tsayar ajiya don yanayi daban-daban) yana da daraja don samar da gwaje-gwaje tare da bayanai tsayawa, da ake iya hulɗa da su.

Mafi mahimmanci, ganewa game da **kyakkyawan aiki** yana haɗi wa ingancin gwaje-gwaje: gogewa `beforeEach` don **saɓon yanayin kowane gwaje-gwaje** ya tabbatar da **ware-ware** (gwaje-gwaje ba sa rinjayi juna — mahimmanci untuk gwaje-gwaje da aka iya dogara), **tsaftaci a cikin teardown** ya hana yanayin da ta rage da ya cause flaky, gwaje-gwaje da ya dog jihar (tushe gida na flakiness), da **ba a damje mutable yanayin gida gwaje-gwaje** ya guje order-dependence da flakiness.

Wadannan aiki suna goyan bayan ware-ware da determinism da gwaje-gwaje masu kyau ke buƙatar.

Tun gwaje-gwaje ke buƙatar shirya da tsaftaci tsayawa, da tun fixtures da setup/teardown (amfani sosai, tare da tsayawa ware-ware da tsaftaci) rage maimaita da tabbatar da yanayin ware-ware, deterministic da gwaje-gwaje masu aminci ke dogara, ganewa test fixtures da setup/teardown yana da daraja, ilimin da ya dogara — mahimmanci don rubuta gwaje-gwaje masu tsatsa, ware-ware, masu tsari, goyan jiya ware-ware da determinism da suke bambanta gwaje-gwaje masu aminci daga flaky gida, wata sana'ar da aka amfani a tsarawa nearly kowane gida gwaje-gwaje.