# no-unnecessary-polyfills

📝 Enforce the use of built-in methods instead of unnecessary polyfills.

💼 This rule is enabled in the following [configs](https://github.com/sindresorhus/eslint-plugin-unicorn#recommended-config): ✅ `recommended`, ☑️ `unopinionated`.

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This rule helps to use existing methods instead of using extra polyfills.

## Examples

package.json

```js
// package.json
{
	"engines": {
		"node": ">=8"
	}
}

// ❌
import assign from 'object-assign';
const object = assign(target, source);
```

```js
// ✅
const object = Object.assign(target, source);
```

```js
// package.json
{
	"engines": {
		"node": "4"
	}
}

// ✅
import assign from 'object-assign'; // Passes as Object.assign is not supported
```

## Options

Type: `object`

### targets

Type: `string | string[] | object`

Specify the target versions, which could be a Browserslist query or a targets object. See the [core-js-compat `targets` option](https://github.com/zloirock/core-js/tree/HEAD/packages/core-js-compat#targets-option) for more info.

If the option is not specified, the target versions are defined using standard [`Browserslist`](https://browsersl.ist) config discovery with the `production` environment, or as a last resort, the `engines` field in package.json.

```js
'unicorn/no-unnecessary-polyfills': [
	'error',
	{
		targets: 'node >=12',
	},
]
```

```js
'unicorn/no-unnecessary-polyfills': [
	'error',
	{
		targets: [
			'node 14.1.0',
			'chrome 95',
		],
	},
]
```

```js
'unicorn/no-unnecessary-polyfills': [
	'error',
	{
		targets: {
			node: 'current',
			firefox: '15',
		},
	},
]
```