@e18e/eslint-plugin

The official e18e ESLint plugin for modernizing JavaScript/TypeScript code and improving performance.

This plugin focuses on applying the e18e community's best practices and advise to JavaScript/TypeScript codebases.

Overview

There are a few categories of rules in this plugin:

• Modernization - New syntax and APIs which improve code readability and performance
• Module replacements - Community recommended alternatives to popular libraries, focused on performance and size
• Performance improvements - Patterns that can be optimized for better runtime performance

Each of these can be enabled individually, or you can use the recommended configuration to enable all rules.

Installation

npm install --save-dev @e18e/eslint-plugin

Usage

Add the plugin to your eslint.config.js:

import e18e from '@e18e/eslint-plugin';

export default [
  // Use the recommended configuration (includes all categories)
  e18e.configs.recommended,

  // Or use specific category configurations
  e18e.configs.modernization,
  e18e.configs.moduleReplacements,
  e18e.configs.performanceImprovements,

  // Or configure rules manually
  {
    plugins: {
      e18e
    },
    rules: {
      'e18e/prefer-array-at': 'error',
      'e18e/prefer-array-fill': 'error',
      'e18e/prefer-includes': 'error'
    }
  }
];

Usage with oxlint

If you're using oxlint, you can enable the e18e plugin by adding it to your .oxlintrc.json file:

{
  "jsPlugins": ["@e18e/eslint-plugin"],
  "rules": {
    "e18e/prefer-includes": "error"
  }
}

You can enable the recommended configuration by copying the rules from each of the ESLint configuration files into your .oxlintrc.json file.

• modernization configuration
• module replacements configuration
• performance improvements configuration

Copying these rules into your rules object will achieve the same effect as using the recommended configuration in ESLint.

[!NOTE] Our type-aware rules depend on TypeScript ESLint's parser, which means they will not work with oxlint at this time.

Linting package.json

Some rules (e.g. ban-dependencies) can be used against your package.json.

You can achieve this by using @eslint/json or jsonc-eslint-parser.

For example, with @eslint/json and eslint.config.js:

import e18e from '@e18e/eslint-plugin';
import json from '@eslint/json';
import {defineConfig} from 'eslint/config';

export default defineConfig([
  {
    files: ['package.json'],
    language: 'json/json',
    plugins: {
      e18e,
      json
    },
    extends: ['e18e/recommended'],
  }
]);

Or with jsonc-eslint-parser and eslint.config.js:

import e18e from '@e18e/eslint-plugin';
import jsonParser from 'jsonc-eslint-parser';
import {defineConfig} from 'eslint/config';

export default defineConfig([
  {
    files: ['package.json'],
    languageOptions: {
      parser: jsonParser
    },
    plugins: {
      e18e
    },
    extends: ['e18e/recommended'],
  }
]);

Read more at the @eslint/json docs and jsonc-eslint-parser docs.

Rules

Legend:

• ✅ = Yes / Enabled
• ✖️ = No / Disabled
• 💡 = Has suggestions (requires user confirmation for fixes)
• 🔶 = Optionally uses types (works without TypeScript but more powerful with it)

Modernization

Module replacements

Performance improvements

Sponsors

License

MIT