@scottnonnenberg/eslint-config-thehelp

Because the tools can help us write better code. Use this package directly, or fork it and make it your own! :0)

Blog post announcing this project: https://blog.scottnonnenberg.com/eslint-part-1-exploration/

Quickstart

npm install @scottnonnenberg/eslint-config-thehelp --save-dev

In your ESLint config (I prever .eslintrc.js), extend this project's default configuration:

module.exports = {
  extends: [
    '@scottnonnenberg/thehelp',
  ],
};

As always, you can override any settings provided in this package in your configuration's rules object.

Configurations in this project

1. @scottnonnenberg/thehelp - Basic good, modern javascript practices. Node.js and CommonJS.
2. @scottnonnenberg/thehelp/functional - Eliminating mutation of data and all loops, in favor of functional design.
3. @scottnonnenberg/thehelp/react - rules for JSX and React component structure, as well as accessibility.
4. @scottnonnenberg/thehelp/scripts - a looser configuration appropriate for your project's scripts/ directory. For example, allows use of devDependencies.
5. @scottnonnenberg/thehelp/test - a configuration appropriate for your projects test/ directory, bringing in two new plugins, the mocha env, and allowing use of devDependencies.

Typescript-specific configuration:

1. @scottnonnenberg/typescript - Because Typescript is what you should be writing, not plain Javascript!
2. @scottnonnenberg/testTypescript - Some rules disabled in /test are duplicated by typescript plugin.

Prettier-specific configuration, turning off formatting rules that prettier takes care of for you.

1. @scottnonnenberg/thehelp/prettier
2. @scottnonnenberg/thehelp/prettierReact
3. @scottnonnenberg/thehelp/prettierTypescript

Peer Dependencies

Take a look at package.json for its peerDependencies list.

Five dependencies are required.

Optional peer dependencies will need to be installed if you use additional configurations beyond the default:

• /react requires the react and jsx-a11y plugins.
• /test requires the bdd and chai-expect plugins
• /typescript requires typescript, and @typescript-eslint plugin and parser modules.
• /functional requires immutable and no-loops plugins.

Key configuration

I've left @scottnonnenberg/thehelp/absolute-or-current-dir disabled by default, but I do recommend it! If you enabled it you'll also need to disable 'import/no-internal-modules'. And, to allow eslint-plugin-import to do its magic, you will need to tell it where to find your modules. I use this in my project's root directory:

{
  settings: {
    'import/resolver': {
      node: {
        paths: [__dirname],
      },
      // If using typescript
      typescript: {
        project: ['./tsconfig.json'],
      },
    },
  },
}

If using react config, you can get more precise deprecation warnings by setting your React version:

{
  react: {
    version: '17.0.2',
  },
}

If using /typescript config, the rules enabled need type information. You need to point it to your tsconfig.json:

{
  parserOptions: {
    project: ['./tsconfig.json'],
  },
}

ESLint can also get really slow when you use typescript linting, because some of the rules need to gather full type information. I would recommend using ESLint's caching option:

{
  "scripts": {
    "lint": "eslint . --cache --max-warnings 0 --ext .ts,.tsx",
    "clean": "rm .eslintcache",
  }
}

My principles for rules

I want rules to specify the 98% case. /* eslint-disable [rules] */ and // eslint-disable-line will cover the rest. I can periodically search for those exceptions and reconsider their justification. Note: this configuration enables reportUnusedDisableDirectives, which means that your eslint-disable clauses will result in warnings if no error was actually prevented.

Next, I believe strongly that all style mandates for a project should have automated tools which verify them. I’ve spent way, way too long talking about style in pull request reviews. Yes, some things can't be verified very easily in an automated fashion. Get creative to implement new verification schemes (write an ESLint plugin!). If you still can't do that, then make as few as possible of these kinds of manual requirements.

Details for this project:

• All rules from all plugins must be included. This is easy with npm scripts using eslint-find-rules.
• Rules are in alphabetical order: first core eslint rules, then plugins sorted by name.
• Always use 'error' or 'off' instead of 0 and 2. Numbers are for real config values.
• No warnings. either disallow it completely, or don't worry about it.
• All 'off' rules must have a reason mentioned.
• Configuration should be nothing but 'error' if it matches the default settings for the rule.

Contributing

This project uses standard-version to release new versions, automatically updating the version number and changelog based on commit messages in standard format. husky and validate-commit-msg are used to ensure all commit messages match the expected format (see package.json for the configuration details).

It takes some getting used to, but this configuration is absolutely worthwhile. A changelog is way easier to understand than the chaos of a raw commit stream, especially with standard-version providing direct links to bugs, commits and commit ranges.

License

(The MIT license)

Copyright (c) 2016 Scott Nonnenberg scott@nonnenberg.com

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.