# @voxpelli/eslint-config

[![npm version](https://img.shields.io/npm/v/@voxpelli/eslint-config.svg?style=flat)](https://www.npmjs.com/package/@voxpelli/eslint-config)
[![npm downloads](https://img.shields.io/npm/dm/@voxpelli/eslint-config.svg?style=flat)](https://www.npmjs.com/package/@voxpelli/eslint-config)
[![neostandard javascript style](https://img.shields.io/badge/code_style-neostandard-7fffff?style=flat&labelColor=ff80ff)](https://github.com/neostandard/neostandard)
[![Follow @voxpelli@mastodon.social](https://img.shields.io/mastodon/follow/109247025527949675?domain=https%3A%2F%2Fmastodon.social&style=social)](https://mastodon.social/@voxpelli)

My personal [ESLint](https://eslint.org/) config – a superset of the [neostandard](https://github.com/neostandard/neostandard) base config that I co-created and co-maintain.

This config contains a couple of more opinionated checks that I find helpful in my projects.

## Install

To easily install correct peer dependencies, you can use [`install-peerdeps`](https://www.npmjs.com/package/install-peerdeps):

```bash
install-peerdeps --dev @voxpelli/eslint-config
```

## Usage

Add an `eslint.config.js` (or `eslint.config.mjs` if your project is CJS) that exports this config:

```js
export { default } from '@voxpelli/eslint-config';
```

If you need to configure something, instead do:

```js
import { voxpelli } from '@voxpelli/eslint-config';

export default voxpelli({
  cjs: true,     // Ensures the config has rules fit for a CJS context rather than an ESM context
  noMocha: true, // By standard this config expects tests to be of the Mocha kind, but one can opt out
});
```

You can also do custom extensions:

```js
import { voxpelli } from '@voxpelli/eslint-config';

export default [
  ...voxpelli({
    // Config options
  }),
  {
    // Custom ESLint config
  },
];
```

###

## How does this differ from pure [neostandard](https://github.com/neostandard/neostandard)?

* :stop_sign: = changed to `error` level
* :warning: = changed to `warn` level
* :mute: = deactivated
* :wrench: = changed config

### :wrench: Changed [neostandard](https://github.com/neostandard/neostandard) rules

* :wrench: [`@stylistic/comma-dangle`](https://eslint.org/docs/rules/comma-dangle) – *changed* – set to enforce dangling commas in arrays, objects, imports and exports
* :wrench: [`no-unused-vars`](https://eslint.org/docs/rules/no-unused-vars) – *changed* – sets `"args": "all", "argsIgnorePattern": "^_",` because I personally don't feel limited by [Express error handlers](https://github.com/standard/standard/issues/419#issuecomment-718186130) + wants to stay in sync with TypeScript `noUnusedParameters`

### :heavy_plus_sign: Added ESLint core rules

* :warning: [`func-style`](https://eslint.org/docs/rules/func-style) – disallows function declarations, good to be consistent with how functions are declared
* :warning: [`no-console`](https://eslint.org/docs/rules/no-console) – warns on existence of `console.log` and similar, as they are mostly used for debugging and should not be committed
* :stop_sign: [`no-constant-binary-expression`](https://eslint.org/docs/rules/no-constant-binary-expression) – errors when binary expressions are detected to constantly evaluate a specific way
* :stop_sign: [`no-nonoctal-decimal-escape`](https://eslint.org/docs/rules/no-nonoctal-decimal-escape) – there's no reason not to ban it
* :stop_sign: [`no-unsafe-optional-chaining`](https://eslint.org/docs/rules/no-unsafe-optional-chaining) – enforces one to be careful with `.?` and not use it in ways that can inadvertently cause errors or `NaN` results
* :warning: [`no-warning-comments`](https://eslint.org/docs/rules/no-warning-comments) – warns of the existence of `FIXME` comments, as they should always be fixed before pushing
* :stop_sign: [`object-shorthand`](https://eslint.org/docs/rules/object-shorthand) – requires the use of object shorthands for properties, more tidy

### :package: Added ESLint rule packages

* [`plugin:jsdoc/recommended`](https://github.com/gajus/eslint-plugin-jsdoc#rules)
* [`plugin:mocha/recommended`](https://github.com/lo1tuma/eslint-plugin-mocha#rules)
* [`plugin:n/recommended`](https://github.com/eslint-community/eslint-plugin-n#-rules)
* [`plugin:promise/recommended`](https://github.com/eslint-community/eslint-plugin-promise#rules)
* [`plugin:security/recommended`](https://github.com/eslint-community/eslint-plugin-security#rules)
* [`plugin:unicorn/recommended`](https://github.com/sindresorhus/eslint-plugin-unicorn#rules)

#### :wrench: Overrides of added ESLint rule packages

* :mute: [`jsdoc/check-types`](https://github.com/gajus/eslint-plugin-jsdoc/blob/main/docs/rules/check-types.md) – *deactivated* – to improve use with [types in js](https://github.com/voxpelli/types-in-js).
* :mute: [`jsdoc/no-undefined-types`](https://github.com/gajus/eslint-plugin-jsdoc/blob/main/docs/rules/no-undefined-types.md) – *deactivated* – to improve use with [types in js](https://github.com/voxpelli/types-in-js).
* :mute: [`jsdoc/require-jsdoc`](https://github.com/gajus/eslint-plugin-jsdoc/blob/main/docs/rules/require-jsdoc.md) – *deactivated* – to improve use with [types in js](https://github.com/voxpelli/types-in-js).
* :mute: [`jsdoc/require-param-description`](https://github.com/gajus/eslint-plugin-jsdoc/blob/main/docs/rules/require-param-description.md) – *deactivated* – to improve use with [types in js](https://github.com/voxpelli/types-in-js).
* :mute: [`jsdoc/require-property-description`](https://github.com/gajus/eslint-plugin-jsdoc/blob/main/docs/rules/require-property-description.md) – *deactivated* – to improve use with [types in js](https://github.com/voxpelli/types-in-js).
* :mute: [`jsdoc/require-returns-description`](https://github.com/gajus/eslint-plugin-jsdoc/blob/main/docs/rules/require-returns-description.md) – *deactivated* – to improve use with [types in js](https://github.com/voxpelli/types-in-js).
* :mute: [`jsdoc/require-yields`](https://github.com/gajus/eslint-plugin-jsdoc/blob/main/docs/rules/require-yields.md) – *deactivated* – to improve use with [types in js](https://github.com/voxpelli/types-in-js).
* :wrench: [`jsdoc/tag-lines`](https://github.com/gajus/eslint-plugin-jsdoc/blob/main/docs/rules/tag-lines.md) – *changed* – to enforce an empty line between description and tags, but disallow them elsewhere.
* :mute: [`jsdoc/valid-types`](https://github.com/gajus/eslint-plugin-jsdoc/blob/main/docs/rules/valid-types.md) – *deactivated* – to improve use with [types in js](https://github.com/voxpelli/types-in-js).

* :mute: [`mocha/no-mocha-arrows`](https://github.com/lo1tuma/eslint-plugin-mocha/blob/master/docs/rules/no-mocha-arrows.md) – *deactivated* – while [Mocha discourages arrow functions](https://mochajs.org/#arrow-functions) I find it more readable to use them + I find it safe when combined with type checking as then the type checking will notify one when one tries to do a `this.setTimeout()` or similar in an arrow function where there is no such local context

* :mute: [`n/no-process-exit`](https://github.com/eslint-community/eslint-plugin-n/blob/master/docs/rules/no-process-exit.md) – *deactivated* – added by `plugin:n/recommended`, but deactivated in favor of [`unicorn/no-process-exit`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules/no-process-exit.md)

* :mute: [`security/detect-object-injection`](https://github.com/eslint-community/eslint-plugin-security/blob/main/docs/rules/detect-object-injection.md) – *deactivated* – causes too many false errors
* :mute: [`security/detect-unsafe-regex`](https://github.com/eslint-community/eslint-plugin-security/blob/main/docs/rules/detect-unsafe-regex.md) – *deactivated* – at least early on wasn't very stable

* :wrench: [`unicorn/catch-error-name`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules/catch-error-name.md) – *changed* – I prefer `err` over `error` as I find `error`to be a far too similar name to the built in `Error` class
* :mute: [`unicorn/explicit-length-check`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules/explicit-length-check.md) – *deactivated* – I don't see an issue with `if (string.length)` instead of `if (string.length !== 0)`
* :warning: [`unicorn/unicorn/no-await-expression-member`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules/unicorn/no-await-expression-member.md) – *changed* – eg. useful in chai tests
* :warning: [`unicorn/unicorn/no-negated-condition`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules/unicorn/no-negated-condition.md) – *deactivated* – turned off, there are valid cases for this, so it simply gets noisy
* :mute: [`unicorn/numeric-separators-style`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules/numeric-separators-style.md) – *deactivated* – currently not enough good support for this in engines
* :warning: [`unicorn/prefer-add-event-listener`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules/prefer-add-event-listener.md) – *changed* – set to `warn` instead of `error`
* :warning: [`unicorn/prefer-event-target`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules//prefer-event-target.md) – *changed* – set to `warn` instead of `error`
* :mute: [`unicorn/prefer-module`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules/prefer-module.md) – *deactivated*  – only useful when you know you're targetting ESM
* :warning: [`unicorn/prefer-spread`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules/prefer-spread.md) – *changed* – set to `warn` instead of `error`
* :warning: [`unicorn/prefer-string-replace-all`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules/prefer-string-replace-all.md) – *changed* – set to `warn` instead of `error`
* :mute: [`unicorn/prevent-abbreviations`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules/prevent-abbreviations.md) – *deactivated* – same as `unicorn/catch-error-name`, I prefer an abbreviated `err` over a non-abbreviated `error`because the latter is too similar to `Error` for my taste
* :wrench: [`unicorn/switch-case-braces`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules/switch-case-braces.md) – *changed* – I prefer to avoid braces in `case` statements rather than enforcing them

### :heavy_plus_sign: Additional standalone ESLint rules

* :stop_sign: [`@stylistic/quote-props`](https://eslint.style/rules/ts/quote-props) – requires properties to be quoted when needed but otherwise disallows it

* :warning: [`es-x/no-exponential-operators`](https://eslint-community.github.io/eslint-plugin-es-x/rules/no-exponential-operators.html) – disallows the use of the `**` operator, as that's in most cases a mistake and one really meant to write `*`

<!-- * :warning: [`import/no-deprecated`](https://github.com/import-js/eslint-plugin-import/blob/main/docs/rules/no-deprecated.md) – disallows the use of explicitly deprecated code (code marked with `@deprecated`)
* :stop_sign: [`import/no-order`](https://github.com/import-js/eslint-plugin-import/blob/main/docs/rules/no-order.md) – enforces a specific ordering of imports -->

* :warning: [`n/prefer-global/console`](https://github.com/eslint-community/eslint-plugin-n/blob/master/docs/rules/prefer-global/console.md)
* :warning: [`n/prefer-promises/fs`](https://github.com/eslint-community/eslint-plugin-n/blob/master/docs/rules/prefer-promises/fs.md)
* :warning: [`n/no-process-env`](https://github.com/eslint-community/eslint-plugin-n/blob/master/docs/rules/no-process-env.md)
* :stop_sign: [`n/no-sync`](https://github.com/eslint-community/eslint-plugin-n/blob/master/docs/rules/no-sync.md)

* :stop_sign: [`promise/prefer-await-to-then`](https://github.com/eslint-community/eslint-plugin-promise/blob/main/docs/rules/prefer-await-to-then.md)

* :stop_sign: [`sort-destructure-keys/sort-destructure-keys`](https://github.com/mthadley/eslint-plugin-sort-destructure-keys)

* :stop_sign: [`unicorn/consistent-destructuring`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/main/docs/rules/consistent-destructuring.md) – while unicorn dropped it from their recommended config I still like it, see [#283](https://github.com/voxpelli/eslint-config/issues/283)

## ESM specific rules

Unless one configures `cjs: true` these additional rules will be applied:

#### :wrench: Overrides of rules

* :warning: [`func-style`](https://eslint.org/docs/rules/func-style) – enforces function declarations whenever an arrow function isn't used. Better to do `export function foo () {` than `export const foo = function () {`
* :stop_sign: [`unicorn/prefer-module`](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/master/docs/rules/prefer-module.md) – *changed* – restored to its `plugin:unicorn/recommended` value of `error`

## Can I use this in my own project?

You may want to use [neostandard](https://github.com/neostandard/neostandard) instead, it's the general base config that I help maintain for the community.

I do maintain this project though as if multiple people are using it, so sure, you can use it, but its ultimate purpose is to support my projects.

I do follow  [semantic versioning](https://semver.org/), so the addition or tightening of any checks will trigger major releases whereas minor and patch releases should only ever have relaxation of rules and bug fixes.

## Alternatives

* [`neostandard`](https://github.com/neostandard/neostandard)
* [`xo`](https://github.com/xojs/xo)

## See also

* [`voxpelli/ghatemplates`](https://github.com/voxpelli/ghatemplates) – the templates I use with [`ghat`](https://github.com/fregante/ghat) to update GitHub Actions in my projects
* [`voxpelli/renovate-config-voxpelli`](https://github.com/voxpelli/renovate-config-voxpelli) – the shareable [renovate setup](https://docs.renovatebot.com/config-presets/) I use in my projects
* [`voxpelli/tsconfig`](https://github.com/voxpelli/tsconfig) – the shareable `tsconfig.json` setup I use in my projects