eslint-plugin-clsx/README.md

An ESLint plugin for clsx/classnames

# eslint-plugin-clsx

An ESLint plugin for clsx/classnames

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* [Installation](#Installation)
* [Usage](#Usage)
* [Rules](#Rules)
* [Presets](#Presets)
  * [Preset usage](#Presetusage)

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## <a name='Installation'></a>Installation

You'll first need to install [ESLint](https://eslint.org):

```sh
npm i eslint --save-dev
```

Next, install `eslint-plugin-clsx`:

```sh
npm install eslint-plugin-clsx --save-dev
```

## <a name='Usage'></a>Usage

Here's an example ESLint configuration that:

* Enables the `recommended` configuration
* Enables an optional/non-recommended rule

```json
{
    "extends": ["plugin:clsx/recommended"],
    "rules": {
        "clsx/no-redundant-clsx": "error"
    }
}
```

## <a name='Rules'></a>Rules

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

⚠️ [Configurations](https://github.com/temoncher/eslint-plugin-clsx#presets) set to warn in.\
✅ Set in the `recommended` [configuration](https://github.com/temoncher/eslint-plugin-clsx#presets).\
🔧 Automatically fixable by the [`--fix` CLI option](https://eslint.org/docs/user-guide/command-line-interface#--fix).

| Name                                                                                           | Description                                                     | ⚠️ | 🔧 |
| :--------------------------------------------------------------------------------------------- | :-------------------------------------------------------------- | :- | :- |
| [forbid-array-expressions](docs/rules/forbid-array-expressions.md)                             | forbid usage of array expressions inside clsx                   | ✅  | 🔧 |
| [forbid-false-inside-object-expressions](docs/rules/forbid-false-inside-object-expressions.md) | forbid usage of false literal inside object expressions of clsx | ✅  | 🔧 |
| [forbid-true-inside-object-expressions](docs/rules/forbid-true-inside-object-expressions.md)   | forbid usage of true literal inside object expressions of clsx  | ✅  | 🔧 |
| [no-redundant-clsx](docs/rules/no-redundant-clsx.md)                                           | disallow redundant clsx usage                                   | ✅  | 🔧 |
| [no-spreading](docs/rules/no-spreading.md)                                                     | forbid usage of object expression inside clsx                   | ✅  | 🔧 |
| [prefer-logical-over-objects](docs/rules/prefer-logical-over-objects.md)                       | forbid usage of object expression inside clsx                   |    | 🔧 |
| [prefer-merged-neighboring-elements](docs/rules/prefer-merged-neighboring-elements.md)         | enforce merging of neighboring elements                         | ✅  | 🔧 |
| [prefer-objects-over-logical](docs/rules/prefer-objects-over-logical.md)                       | forbid usage of logical expressions inside clsx                 |    | 🔧 |

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

## <a name='Presets'></a>Presets

|   | Name | Description |
|:--|:-----|:------------|
| ✅ | `recommended` | enables all recommended rules in this plugin |
|   | `all` | enables all rules in this plugin |

### <a name='Presetusage'></a>Preset usage

Presets are enabled by adding a line to the `extends` list in your config file. For example, to enable the `recommended` preset, use:

```js
import { defineConfig } from "eslint/config";
import clsx from "eslint-plugin-clsx";

export default defineConfig(
  /* Main config */
  clsx.configs.flat.recommended,
);
```

or in legacy config (.eslintrc.json)

```json
{
    "extends": ["plugin:clsx/recommended"]
}
```

## <a name='Settings'></a>Settings

This rule can optionally be configured with an object that represents imports that should be considered an clsx usage

```js
import { defineConfig } from "eslint/config";
import clsx from "eslint-plugin-clsx";

export default defineConfig(
  {
    plugins: { clsx },
    settings: {
      clsxOptions: {
        myclsx: ["default", "clsx"],
      },
    },
    rules: {
      'clsx/no-redundant-clsx': 'error',
    }
  }
);
```

or in legacy config (.eslintrc.json)

```json
{
    "settings": {
        "clsxOptions": {
            "myclsx": "default"
        }
    }
}
```

Examples of **incorrect** code for the `{ myclsx: 'default' }` setting (with no-redundant-clsx rule enabled):

```js
import mc from 'myclsx';

const singleClasses = mc('single-class');
```

Examples of **incorrect** code for the `{ myclsx: 'cn' }` setting (with no-redundant-clsx rule enabled):

```js
import { cn } from 'myclsx';

const singleClasses = cn('single-class');
```

Examples of **incorrect** code for the `{ myclsx: ['default', 'cn'] }` setting (with no-redundant-clsx rule enabled):

```js
import mc, { cn } from 'myclsx';

// both report errors
const singleClasses = cn('single-class');
const singleClasses = mc('single-class');
```

Default setting value is `{ clsx: ['default', 'clsx'], classnames: 'default' }`