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# 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](https://facebook.github.io/jest/docs/en/setup-teardown.html)