GoScrobble/web/node_modules/eslint-plugin-jest/docs/rules/expect-expect.md

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# Enforce assertion to be made in a test body (`expect-expect`)
Ensure that there is at least one `expect` call made in a test.
## Rule details
This rule triggers when there is no call made to `expect` in a test, to prevent
users from forgetting to add assertions.
Examples of **incorrect** code for this rule:
```js
it('should be a test', () => {
console.log('no assertion');
});
test('should assert something', () => {});
```
Examples of **correct** code for this rule:
```js
it('should be a test', () => {
expect(true).toBeDefined();
});
it('should work with callbacks/async', () => {
somePromise().then(res => expect(res).toBe('passed'));
});
```
## Options
```json
{
"jest/expect-expect": [
"error",
{
"assertFunctionNames": ["expect"]
}
]
}
```
### `assertFunctionNames`
This array option specifies the names of functions that should be considered to
be asserting functions. Function names can use wildcards i.e `request.*.expect`,
`request.**.expect`, `request.*.expect*`
Examples of **incorrect** code for the `{ "assertFunctionNames": ["expect"] }`
option:
```js
/* eslint jest/expect-expect: ["error", { "assertFunctionNames": ["expect"] }] */
import { expectSaga } from 'redux-saga-test-plan';
import { addSaga } from '../src/sagas';
test('returns sum', () => {
expectSaga(addSaga, 1, 1).returns(2).run();
});
```
Examples of **correct** code for the
`{ "assertFunctionNames": ["expect", "expectSaga"] }` option:
```js
/* eslint jest/expect-expect: ["error", { "assertFunctionNames": ["expect", "expectSaga"] }] */
import { expectSaga } from 'redux-saga-test-plan';
import { addSaga } from '../src/sagas';
test('returns sum', () => {
expectSaga(addSaga, 1, 1).returns(2).run();
});
```
Since the string is compiled into a regular expression, you'll need to escape
special characters such as `$` with a double backslash:
```js
/* eslint jest/expect-expect: ["error", { "assertFunctionNames": ["expect\\$"] }] */
it('is money-like', () => {
expect$(1.0);
});
```
Examples of **correct** code for working with the HTTP assertions library
[SuperTest](https://www.npmjs.com/package/supertest) with the
`{ "assertFunctionNames": ["expect", "request.**.expect"] }` option:
```js
/* eslint jest/expect-expect: ["error", { "assertFunctionNames": ["expect", "request.**.expect"] }] */
const request = require('supertest');
const express = require('express');
const app = express();
describe('GET /user', function () {
it('responds with json', function (done) {
request(app).get('/user').expect('Content-Type', /json/).expect(200, done);
});
});
```