ESLint-Config

This is a full opinionated eslint config using multiple plugins supporting Typescript, JavaScript, Markdown, CSS, HTML, JSON and JSON5.

Features

• Comprehensive ruleset: Pre-configured for modern Web and Node.js development.
• Reusable TSConfigs: Includes optimized TypeScript configurations for Node and Browser environments.
• Global Type Enhancements: Automatically integrates @mephisto5558/better-types for improved global types.

How to use

1. Installation

1. Install

   npm install --save-dev @mephisto5558/eslint-config

2. Add this script (or any other script calling eslint) to your package.json:

   "lint": "eslint . --cache --cache-location ./node_modules/.cache/eslint/",

2. Use in eslint.config.ts / js / cjs / mjs

import config, { tsGlob, jsGlob } from '@mephisto5558/eslint-config';

export default [
  ...config,
  {
    name: 'your-project-overrides',
    files: [`*${tsGlob}`, `*${jsGlob}`],
    rules: {
      ...
    }
  }
] as typeof config;

See one of my other project's ESLint config for a more complex example using getModifiedRule: Teufelsbot.

3. Reusable TSConfigs (Optional)

You can extend your tsconfig.json from this package to get secure defaults:

For Node.js projects:

{ 
  "extends": "@mephisto5558/eslint-config/tsconfigs/node/tsconfig.check.json"
}

For Browser projects:

{ 
  "extends": "@mephisto5558/eslint-config/tsconfigs/browser/tsconfig.check.json"
}

Use the tsconfig.build.json variants for your build pipeline.

4. Run

Run normally:

npm run lint

Run with autofix enabled:

npm run lint -- --fix

Rule Severity

The rules are divided into three severity levels: error, warn, and off.

• error: Rules that indicate potential runtime errors, syntax errors, or unsafe behavior. These should always be fixed. Examples:

  • @typescript-eslint/no-array-delete: Disallows using delete on array elements, which creates sparse arrays and is often not the intended behavior.
  • regexp/no-invalid-regexp: Reports invalid regular expressions in RegExp constructors.
  • eslint/no-const-assign: Disallows reassigning constants.

• warn: Rules that point to style issues, best practices, or potential typos, but do not cause runtime errors. These should generally be fixed to improve code quality. Examples:

  • @stylistic/quotes: Enforces the use of single (') quotes.
  • unicorn/no-for-loop: Suggests using for...of instead of C-style for loops.
  • jsdoc/check-syntax: Ensures that the JSDoc syntax is valid.

• off: Rules that are disabled. The reasons for this are:

  • Covered by other rules: The functionality is already handled by another, often more specific, rule. Example:
    • eslint/no-dupe-class-members is disabled because @typescript-eslint/no-dupe-class-members handles this better for TypeScript code.
  • Not (sufficiently) configurable: The rule does not fit the desired coding style and cannot be adjusted accordingly. Example:
    • @stylistic/object-property-newline is too restrictive in formatting objects.
  • Personal preference: The rule deliberately contradicts the coding style of my projects. Example:
    • unicorn/no-array-reduce is disabled because I prefer Array.prototype.reduce.