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:[email protected] - ISC license.
• (c) 2016 Jamund Ferguson mailto:[email protected] - ISC license.