Disallow setup and teardown hooks (no-hooks)

Jest provides global functions for setup and teardown tasks, which are called before/after each test case and each test suite. The use of these hooks promotes shared state between tests.

Rule Details

This rule reports for the following function calls:

• beforeAll
• beforeEach
• afterAll
• afterEach

Examples of incorrect code for this rule:

```js / eslint jest/no-hooks: “error” /

function setupFoo(options) { / … / }

function setupBar(options) { / … / }

describe(‘foo’, () => { let foo;

beforeEach(() => { foo = setupFoo(); });

afterEach(() => { foo = null; });

it(‘does something’, () => { expect(foo.doesSomething()).toBe(true); });

describe(‘with bar’, () => { let bar;

beforeEach(() => {
  bar = setupBar();
});

afterEach(() => {
  bar = null;
});

it('does something with bar', () => {
  expect(foo.doesSomething(bar)).toBe(true);
});

}); }); ```

Examples of correct code for this rule:

```js / eslint jest/no-hooks: “error” /

function setupFoo(options) { / … / }

function setupBar(options) { / … / }

describe(‘foo’, () => { it(‘does something’, () => { const foo = setupFoo(); expect(foo.doesSomething()).toBe(true); });

it(‘does something with bar’, () => { const foo = setupFoo(); const bar = setupBar(); expect(foo.doesSomething(bar)).toBe(true); }); }); ```

Options

json { "jest/no-hooks": [ "error", { "allow": ["afterEach", "afterAll"] } ] }

allow

This array option controls which Jest hooks are checked by this rule. There are four possible values:

• "beforeAll"
• "beforeEach"
• "afterAll"
• "afterEach"

By default, none of these options are enabled (the equivalent of { "allow": [] }).

Examples of incorrect code for the { "allow": ["afterEach"] } option:

```js / eslint jest/no-hooks: [“error”, { “allow”: [“afterEach”] }] /

function setupFoo(options) { / … / }

let foo;

beforeEach(() => { foo = setupFoo(); });

afterEach(() => { jest.resetModules(); });

test(‘foo does this’, () => { // … });

test(‘foo does that’, () => { // … }); ```

Examples of correct code for the { "allow": ["afterEach"] } option:

```js / eslint jest/no-hooks: [“error”, { “allow”: [“afterEach”] }] /

function setupFoo(options) { / … / }

afterEach(() => { jest.resetModules(); });

test(‘foo does this’, () => { const foo = setupFoo(); // … });

test(‘foo does that’, () => { const foo = setupFoo(); // … }); ```

When Not To Use It

If you prefer using the setup and teardown hooks provided by Jest, you can safely disable this rule.

Further Reading

• Jest docs - Setup and Teardown