close
Rslint

    require-hook

    Configuration

    rslint.config.ts
    import { defineConfig, jestPlugin } from '@rslint/core';

export default defineConfig([
  jestPlugin.configs.recommended,
  {
    rules: {
      'jest/require-hook': 'error',
    },
  },
]);

    Rule Details

    Require setup and teardown code to be within a Jest lifecycle hook (beforeEach, afterEach, beforeAll, afterAll).

    It's common when writing tests to need setup work before tests run and cleanup afterward. Because Jest executes all describe handlers in a test file before any of the actual tests, setup and teardown done directly in a describe body (or at the top level of the file) can run at the wrong time or leak across suites. This rule pushes that work into the lifecycle hooks instead.

    This rule checks direct statements at the top level of a test file and direct statements within the body of each describe callback. It does not inspect arbitrary statements nested inside control-flow statements or other function callbacks.

    It flags expressions in those scopes except for:

    • import statements
    • const variable declarations, including declarations with initializers
    • Uninitialized let and var declarations
    • let and var declarations initialized directly with null or undefined
    • Classes
    • Types
    • Calls to recognized Jest APIs, such as describe, test / it, lifecycle hooks, expect, and jest.*

    For variable declarations, a declaration containing any other initializer is reported as a whole. For example:

    let spy;                 // valid
let empty = null;        // valid
let notEmpty = create(); // incorrect
const value = create();  // valid

    Examples of incorrect code for this rule:

    import { database, isCity } from '../database';
import { loadCities } from '../api';

jest.mock('../api');

const initializeCityDatabase = () => {
  database.addCity('Vienna');
  database.addCity('San Juan');
  database.addCity('Wellington');
};

const clearCityDatabase = () => {
  database.clear();
};

initializeCityDatabase();

test('that persists cities', () => {
  expect(database.cities.length).toHaveLength(3);
});

test('city database has Vienna', () => {
  expect(isCity('Vienna')).toBeTruthy();
});

test('city database has San Juan', () => {
  expect(isCity('San Juan')).toBeTruthy();
});

describe('when loading cities from the api', () => {
  let consoleWarnSpy = jest.spyOn(console, 'warn');

  loadCities.mockResolvedValue(['Wellington', 'London']);

  it('does not duplicate cities', async () => {
    await database.loadCities();

    expect(database.cities).toHaveLength(4);
  });

  it('logs any duplicates', async () => {
    await database.loadCities();

    expect(consoleWarnSpy).toHaveBeenCalledWith(
      'Ignored duplicate cities: Wellington',
    );
  });
});

clearCityDatabase();

    Examples of correct code for this rule:

    import { database, isCity } from '../database';
import { loadCities } from '../api';

jest.mock('../api');

const initializeCityDatabase = () => {
  database.addCity('Vienna');
  database.addCity('San Juan');
  database.addCity('Wellington');
};

const clearCityDatabase = () => {
  database.clear();
};

beforeEach(() => {
  initializeCityDatabase();
});

test('that persists cities', () => {
  expect(database.cities.length).toHaveLength(3);
});

test('city database has Vienna', () => {
  expect(isCity('Vienna')).toBeTruthy();
});

test('city database has San Juan', () => {
  expect(isCity('San Juan')).toBeTruthy();
});

describe('when loading cities from the api', () => {
  let consoleWarnSpy;

  beforeEach(() => {
    consoleWarnSpy = jest.spyOn(console, 'warn');
    loadCities.mockResolvedValue(['Wellington', 'London']);
  });

  it('does not duplicate cities', async () => {
    await database.loadCities();

    expect(database.cities).toHaveLength(4);
  });

  it('logs any duplicates', async () => {
    await database.loadCities();

    expect(consoleWarnSpy).toHaveBeenCalledWith(
      'Ignored duplicate cities: Wellington',
    );
  });
});

afterEach(() => {
  clearCityDatabase();
});

    Options

    • First argument (optional): object with allowedFunctionCalls
      • allowedFunctionCalls: array of exact callee names that are allowed outside hooks. Names are matched against the full dotted callee name, so helper.setup matches helper.setup() but setup does not.
    { "jest/require-hook": ["error", { "allowedFunctionCalls": ["enableAutoDestroy"] }] }
    import { enableAutoDestroy } from '@vue/test-utils';
import { initDatabase, tearDownDatabase } from './databaseUtils';

enableAutoDestroy(afterEach);

beforeEach(initDatabase);
afterEach(tearDownDatabase);

describe('Foo', () => {
  test('always returns 42', () => {
    expect(global.getAnswer()).toBe(42);
  });
});

    Original Documentation