Enforce best practices for JavaScript promises.
You'll first need to install ESLint:
npm install eslint --save-devNext, install eslint-plugin-promise:
npm install eslint-plugin-promise --save-devNote: If you installed ESLint globally (using the -g flag) then you must also install eslint-plugin-promise globally.
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"] }
💼 Configurations enabled 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. | ||||
| spec-only | Disallow use of non-standard Promise static methods. | ||||
| valid-params | Enforces the proper number of arguments are passed to Promise functions. | ✅ |
- Jamund Ferguson - @xjamundx
- Macklin Underdown - @macklinu
- Aadit M Shah - @aaditmshah
- (c) MMXV jden mailto:jason@denizac.org - ISC license.
- (c) 2016 Jamund Ferguson mailto:jamund@gmail.com - ISC license.
