eslint-plugin-jest-extended/README.md

Eslint rules for Jest Extended

<div align="center">
  <a href="https://eslint.org/">
    <img height="150" src="https://eslint.org/assets/images/logo/eslint-logo-color.svg">
  </a>
  <a href="https://jestjs.io/">
    <img width="150" height="150" vspace="" hspace="25" src="https://jestjs.io/img/jest.png">
  </a>
  <h1>eslint-plugin-jest-extended</h1>
  <p>ESLint plugin for <a href="https://github.com/jest-community/jest-extended">Jest Extended</a></p>
</div>

[![Actions Status](https://github.com/jest-community/eslint-plugin-jest-extended/workflows/Unit%20tests%20%26%20Release/badge.svg?branch=main)](https://github.com/jest-community/eslint-plugin-jest-extended/actions)

## Installation

```
$ yarn add --dev eslint eslint-plugin-jest-extended
```

**Note:** If you installed ESLint globally then you must also install
`eslint-plugin-jest-extended` globally.

## Usage

> [!NOTE]
>
> `eslint.config.js` is supported, though most of the plugin documentation still
> currently uses `.eslintrc` syntax.
>
> Refer to the
> [ESLint documentation on the new configuration file format](https://eslint.org/docs/latest/use/configure/configuration-files-new)
> for more.

Add `jest-extended` to the plugins section of your `.eslintrc` configuration
file. You can omit the `eslint-plugin-` prefix:

```json
{
  "plugins": ["jest-extended"]
}
```

Then configure the rules you want to use under the rules section.

```json
{
  "rules": {
    "jest-extended/prefer-to-be-true": "warn",
    "jest-extended/prefer-to-be-false": "error"
  }
}
```

## Shareable configurations

### Recommended

This plugin does not export a recommended configuration, as the rules provided
by this plugin are about enforcing usage of preferred matchers for particular
patterns, rather than helping to prevent bugs & commonly overlooked traps.

### All

If you want to enable all rules instead of only some you can do so by adding the
`all` configuration to your `.eslintrc` config file:

```json
{
  "extends": ["plugin:jest-extended/all"]
}
```

To enable this configuration with `eslint.config.js`, use
`jestExtended.configs['flat/all']`:

```js
const jestExtended = require('eslint-plugin-jest-extended');

module.exports = [
  {
    files: [
      /* glob matching your test files */
    ],
    ...jestExtended.configs['flat/all'],
  },
];
```

Note that the `all` configuration may change in any release and is thus unsuited
for installations requiring long-term consistency.

## Rules

<!-- begin auto-generated rules list -->

🔧 Automatically fixable by the
[`--fix` CLI option](https://eslint.org/docs/user-guide/command-line-interface#--fix).

| Name                                                                             | Description                            | 🔧  |
| :------------------------------------------------------------------------------- | :------------------------------------- | :-- |
| [prefer-to-be-array](docs/rules/prefer-to-be-array.md)                           | Suggest using `toBeArray()`            | 🔧  |
| [prefer-to-be-false](docs/rules/prefer-to-be-false.md)                           | Suggest using `toBeFalse()`            | 🔧  |
| [prefer-to-be-object](docs/rules/prefer-to-be-object.md)                         | Suggest using `toBeObject()`           | 🔧  |
| [prefer-to-be-true](docs/rules/prefer-to-be-true.md)                             | Suggest using `toBeTrue()`             | 🔧  |
| [prefer-to-have-been-called-once](docs/rules/prefer-to-have-been-called-once.md) | Suggest using `toHaveBeenCalledOnce()` | 🔧  |

<!-- end auto-generated rules list -->

## Credit

- [eslint-plugin-jest](https://github.com/jest-community/eslint-plugin-jest)

## Related Projects

### eslint-plugin-jest

This project aims to provide linting rules to aid in writing tests using jest.

https://github.com/jest-community/eslint-plugin-jest

### eslint-plugin-jest-formatting

This project aims to provide formatting rules (auto-fixable where possible) to
ensure consistency and readability in jest test suites.

https://github.com/dangreenisrael/eslint-plugin-jest-formatting

[fixable]: https://img.shields.io/badge/-fixable-green.svg