3.0 KiB
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:
beforeAllbeforeEachafterAllafterEach
Examples of incorrect code for this rule:
/* 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:
/* 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
{
"jest/no-hooks": [
"error",
{
"allow": ["afterEach", "afterAll"]
}
]
}
allow
This array option whitelists setup and teardown hooks so that this rule does not report their usage as being incorrect. 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:
/* 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:
/* 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.