eslint-plugin-promise

Enforce best practices for JavaScript promises.

• Installation
• Usage
• Rules
• Maintainers
• License

Installation

You'll first need to install ESLint:

npm install eslint --save-dev

Next, install eslint-plugin-promise:

npm install eslint-plugin-promise --save-dev

Note: If you installed ESLint globally (using the -g flag) then you must also install eslint-plugin-promise globally.

Usage

Add promise to the plugins section of your .eslintrc.json configuration file. You can omit the eslint-plugin- prefix:

{
  "plugins": ["promise"]
}

Then configure the rules you want to use under the rules section.

{
  "rules": {
    "promise/always-return": "error",
    "promise/no-return-wrap": "error",
    "promise/param-names": "error",
    "promise/catch-or-return": "error",
    "promise/no-native": "off",
    "promise/no-nesting": "warn",
    "promise/no-promise-in-callback": "warn",
    "promise/no-callback-in-promise": "warn",
    "promise/avoid-new": "warn",
    "promise/no-new-statics": "error",
    "promise/no-return-in-finally": "warn",
    "promise/valid-params": "warn",
    "promise/no-multiple-resolved": "error"
  }
}

or start with the recommended rule set:

• eslint.config.js:

  import pluginPromise from 'eslint-plugin-promise'
  export default [
    // ...
    pluginPromise.configs['flat/recommended'],
  ]

• .eslintrc.*:

  {
    "extends": ["plugin:promise/recommended"]
  }

Rules

💼 Configurations enabled in.
⚠️ Configurations set to warn in.
🚫 Configurations disabled in.
✅ Set in the flat/recommended configuration.
✅ Set in the recommended configuration.
🔧 Automatically fixable by the --fix CLI option.

Name	Description	💼	⚠️	🚫	🔧
always-return	Require returning inside each then() to create readable and reusable Promise chains.	✅
avoid-new	Disallow creating new promises outside of utility libs (use util.promisify instead).			✅
catch-or-return	Enforce the use of catch() on un-returned promises.	✅
no-callback-in-promise	Disallow calling cb() inside of a then() (use util.callbackify instead).		✅
no-multiple-resolved	Disallow creating new promises with paths that resolve multiple times.
no-native	Require creating a Promise constructor before using it in an ES5 environment.			✅
no-nesting	Disallow nested then() or catch() statements.		✅
no-new-statics	Disallow calling new on a Promise static method.	✅			🔧
no-promise-in-callback	Disallow using promises inside of callbacks.		✅
no-return-in-finally	Disallow return statements in finally().		✅
no-return-wrap	Disallow wrapping values in Promise.resolve or Promise.reject when not needed.	✅
param-names	Enforce consistent param names and ordering when creating new promises.	✅
prefer-await-to-callbacks	Prefer async/await to the callback pattern.
prefer-await-to-then	Prefer await to then()/catch()/finally() for reading Promise values.
prefer-catch	Prefer catch to then(a, b)/then(null, b) for handling errors.				🔧
spec-only	Disallow use of non-standard Promise static methods.
valid-params	Enforces the proper number of arguments are passed to Promise functions.		✅

Maintainers

• Jamund Ferguson - @xjamundx
• Macklin Underdown - @macklinu
• Aadit M Shah - @aaditmshah

License

• (c) MMXV jden mailto:jason@denizac.org - ISC license.
• (c) 2016 Jamund Ferguson mailto:jamund@gmail.com - ISC license.