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"
  }
}

or start with the recommended rule set:

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

Rules

| rule | description | recommended | fixable | | -------------------------------------------------------- | -------------------------------------------------------------------------------- | ----------- | -------- | | catch-or-return | Enforces the use of catch() on un-returned promises. | :bangbang: | | | no-return-wrap | Avoid wrapping values in Promise.resolve or Promise.reject when not needed. | :bangbang: | | | param-names | Enforce consistent param names and ordering when creating new promises. | :bangbang: | | | always-return | Return inside each then() to create readable and reusable Promise chains. | :bangbang: | | | no-native | In an ES5 environment, make sure to create a Promise constructor before using. | | | | no-nesting | Avoid nested then() or catch() statements | :warning: | | | no-promise-in-callback | Avoid using promises inside of callbacks | :warning: | | | no-callback-in-promise | Avoid calling cb() inside of a then() (use nodeify instead) | :warning: | | | avoid-new | Avoid creating new promises outside of utility libs (use pify instead) | | | | no-new-statics | Avoid calling new on a Promise static method | :bangbang: | :wrench: | | no-return-in-finally | Disallow return statements in finally() | :warning: | | | valid-params | Ensures the proper number of arguments are passed to Promise functions | :warning: | | | prefer-await-to-then | Prefer await to then()/catch()/finally() for reading Promise values | :seven: | | | prefer-await-to-callbacks | Prefer async/await to the callback pattern | :seven: | | | no-multiple-resolved | Disallow creating new promises with paths that resolve multiple times | | |

Key

| icon | description | | ---------- | ----------------------------------------------- | | :bangbang: | Reports as error in recommended configuration | | :warning: | Reports as warning in recommended configuration | | :seven: | ES2017 Async Await rules | | :wrench: | Rule is fixable with eslint --fix |

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.