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# no-prototype-builtins

[Added in v0.5.0](https://github.com/web-infra-dev/rslint/releases/tag/v0.5.0)
## Configuration

| Preset                   | Configured Value |
| ------------------------ | ---------------- |
| ✅ js.configs.recommended | `"error"`        |


```ts title=rslint.config.ts
import { defineConfig, js } from '@rslint/core';

export default defineConfig([
  js.configs.recommended,
  {
    rules: {
      'no-prototype-builtins': 'error',
    },
  },
]);
```

## Rule Details

This rule disallows calling `Object.prototype` methods directly on object
instances. In particular, it flags calls to `hasOwnProperty`, `isPrototypeOf`,
and `propertyIsEnumerable` invoked as members of a target object. Such calls
can break on objects created with `Object.create(null)` (which do not inherit
from `Object.prototype`) or on objects that define shadowing properties with
the same names.

Examples of **incorrect** code for this rule:

```javascript
var hasBarProperty = foo.hasOwnProperty('bar');
var isPrototypeOfBar = foo.isPrototypeOf(bar);
var barIsEnumerable = foo.propertyIsEnumerable('bar');
```

Examples of **correct** code for this rule:

```javascript
var hasBarProperty = Object.prototype.hasOwnProperty.call(foo, 'bar');
var isPrototypeOfBar = Object.prototype.isPrototypeOf.call(foo, bar);
var barIsEnumerable = {}.propertyIsEnumerable.call(foo, 'bar');
```

## Options

This rule has no options.

## Original Documentation

- [ESLint: no-prototype-builtins](https://eslint.org/docs/latest/rules/no-prototype-builtins)
- [Source code](https://github.com/eslint/eslint/blob/v10.8.1/lib/rules/no-prototype-builtins.js)