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Add no-instanceof-builtin-object rule (#2523)
Co-authored-by: Sindre Sorhus <[email protected]> Co-authored-by: fisker <[email protected]>
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‎docs/rules/no-instanceof-builtin-object.md

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# Disallow `instanceof` with built-in objects
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💼 This rule is enabled in the ✅ `recommended` [config](https://github.com/sindresorhus/eslint-plugin-unicorn#preset-configs-eslintconfigjs).
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🔧 This rule is automatically fixable by the [`--fix` CLI option](https://eslint.org/docs/latest/user-guide/command-line-interface#--fix).
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<!-- end auto-generated rule header -->
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<!-- Do not manually modify this header. Run: `npm run fix:eslint-docs` -->
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Using `instanceof` to determine the type of an object has [limitations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/instanceof#instanceof_and_multiple_realms).
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Therefore, it is recommended to use a safer method, like `Object.prototype.toString.call(foo)` or the npm package [@sindresorhus/is](https://www.npmjs.com/package/@sindresorhus/is) to determine the type of an object.
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## Examples
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```js
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foo instanceof String; // ❌
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typeof foo === 'string'; // ✅
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```
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```js
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foo instanceof Number; // ❌
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typeof foo === 'number'; // ✅
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```
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```js
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foo instanceof Boolean; // ❌
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typeof foo === 'boolean'; // ✅
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```
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```js
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foo instanceof BigInt; // ❌
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typeof foo === 'bigint'; // ✅
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```
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```js
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foo instanceof Symbol; // ❌
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typeof foo === 'symbol'; // ✅
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```
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```js
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foo instanceof Array; // ❌
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Array.isArray(foo); // ✅
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```
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```js
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foo instanceof Function; // ❌
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typeof foo === 'function'; // ✅
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```
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```js
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foo instanceof Object; // ❌
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Object.prototype.toString.call(foo) === '[object Object]'; // ✅
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```
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```js
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import is from '@sindresorhus/is';
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foo instanceof Map; // ❌
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is(foo) === 'Map'; // ✅
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```
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## Options
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### strategy
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Type: `'loose' | 'strict'`\
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Default: `'loose'`
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The matching strategy:
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- `'loose'` - Matches the primitive type (`string`, `number`, `boolean`, `bigint`, `symbol`) constructors, `Function`, and `Array`.
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- `'strict'` - Matches all built-in constructors.
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```js
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"unicorn/no-instanceof-builtin-object": [
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"error",
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{
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"strategy": "strict"
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}
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]
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```
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### include
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Type: `string[]`\
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Default: `[]`
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Specify the constructors that should be validated.
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```js
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"unicorn/no-instanceof-builtin-object": [
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"error",
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{
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"include": [
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"WebWorker",
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"HTMLElement"
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]
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}
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]
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```
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### exclude
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Type: `string[]`\
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Default: `[]`
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Specifies the constructors that should be excluded, with this rule taking precedence over others.
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```js
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"unicorn/no-instanceof-builtin-object": [
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"error",
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{
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"exclude": [
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"String",
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"Number"
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]
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}
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]
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```
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### useErrorIsError
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Type: `boolean`\
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Default: `false`
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Specifies using [`Error.isError()`](https://github.com/tc39/proposal-is-error) to determine whether it is an error object.
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```js
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"unicorn/no-instanceof-builtin-object": [
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"error",
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{
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"strategy": "strict",
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"useErrorIsError": true
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}
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]
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```
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This option will be removed at some point in the future.

‎readme.md

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| [no-for-loop](docs/rules/no-for-loop.md) | Do not use a `for` loop that can be replaced with a `for-of` loop. | ✅ | 🔧 | 💡 |
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| [no-hex-escape](docs/rules/no-hex-escape.md) | Enforce the use of Unicode escapes instead of hexadecimal escapes. | ✅ | 🔧 | |
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| [no-instanceof-array](docs/rules/no-instanceof-array.md) | Require `Array.isArray()` instead of `instanceof Array`. | ✅ | 🔧 | |
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| [no-instanceof-builtin-object](docs/rules/no-instanceof-builtin-object.md) | Disallow `instanceof` with built-in objects | ✅ | 🔧 | |
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| [no-invalid-fetch-options](docs/rules/no-invalid-fetch-options.md) | Disallow invalid options in `fetch()` and `new Request()`. | ✅ | | |
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| [no-invalid-remove-event-listener](docs/rules/no-invalid-remove-event-listener.md) | Prevent calling `EventTarget#removeEventListener()` with the result of an expression. | ✅ | | |
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| [no-keyword-prefix](docs/rules/no-keyword-prefix.md) | Disallow identifiers starting with `new` or `class`. | | | |

‎rules/catch-error-name.js

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import {isRegExp} from 'node:util/types';
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import {findVariable} from '@eslint-community/eslint-utils';
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import avoidCapture from './utils/avoid-capture.js';
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import {renameVariable} from './fix/index.js';
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};
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const {name: expectedName} = options;
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const ignore = options.ignore.map(
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pattern => pattern instanceof RegExp ? pattern : new RegExp(pattern, 'u'),
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pattern => isRegExp(pattern) ? pattern : new RegExp(pattern, 'u'),
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);
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const isNameAllowed = name =>
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name === expectedName

‎rules/error-message.js

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import {getStaticValue} from '@eslint-community/eslint-utils';
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import isShadowed from './utils/is-shadowed.js';
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import {isCallOrNewExpression} from './ast/index.js';
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import builtinErrors from './shared/builtin-errors.js';
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const MESSAGE_ID_MISSING_MESSAGE = 'missing-message';
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const MESSAGE_ID_EMPTY_MESSAGE = 'message-is-empty-string';
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[MESSAGE_ID_NOT_STRING]: 'Error message should be a string.',
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};
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const builtinErrors = [
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// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error
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'Error',
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'EvalError',
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'RangeError',
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'ReferenceError',
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'SyntaxError',
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'TypeError',
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'URIError',
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'InternalError',
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'AggregateError',
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];
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/** @param {import('eslint').Rule.RuleContext} context */
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const create = context => {
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context.on(['CallExpression', 'NewExpression'], expression => {

‎rules/expiring-todo-comments.js

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import path from 'node:path';
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import {isRegExp} from 'node:util/types';
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import {readPackageUpSync} from 'read-package-up';
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import semver from 'semver';
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import * as ci from 'ci-info';
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};
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const ignoreRegexes = options.ignore.map(
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pattern => pattern instanceof RegExp ? pattern : new RegExp(pattern, 'u'),
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pattern => isRegExp(pattern) ? pattern : new RegExp(pattern, 'u'),
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);
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const dirname = path.dirname(context.filename);

‎rules/filename-case.js

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import path from 'node:path';
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import {isRegExp} from 'node:util/types';
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import {
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camelCase,
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kebabCase,
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const options = context.options[0] || {};
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const chosenCases = getChosenCases(options);
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const ignore = (options.ignore || []).map(item => {
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if (item instanceof RegExp) {
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if (isRegExp(item)) {
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return item;
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}
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‎rules/index.js

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import noForLoop from './no-for-loop.js';
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import noHexEscape from './no-hex-escape.js';
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import noInstanceofArray from './no-instanceof-array.js';
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import noInstanceofBuiltinObject from './no-instanceof-builtin-object.js';
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import noInvalidFetchOptions from './no-invalid-fetch-options.js';
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import noInvalidRemoveEventListener from './no-invalid-remove-event-listener.js';
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import noKeywordPrefix from './no-keyword-prefix.js';
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'no-for-loop': createRule(noForLoop, 'no-for-loop'),
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'no-hex-escape': createRule(noHexEscape, 'no-hex-escape'),
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'no-instanceof-array': createRule(noInstanceofArray, 'no-instanceof-array'),
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'no-instanceof-builtin-object': createRule(noInstanceofBuiltinObject, 'no-instanceof-builtin-object'),
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'no-invalid-fetch-options': createRule(noInvalidFetchOptions, 'no-invalid-fetch-options'),
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'no-invalid-remove-event-listener': createRule(noInvalidRemoveEventListener, 'no-invalid-remove-event-listener'),
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'no-keyword-prefix': createRule(noKeywordPrefix, 'no-keyword-prefix'),

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