Skip to main content

Develop with formatjs

Aside from a strong focus on facilitating i18n production pipeline, formatjs also aims to improve i18n DevEx with our eslint-plugin-formatjs.

Linter Installation

npm i -D eslint-plugin-formatjs eslint

Then in your eslint config:

"plugins": ["formatjs"],
"rules": {
"formatjs/no-offset": "error"

Head over to eslint-plugin-formatjs for more details on our rules.

Error Codes

react-intl is designed to fail fast when there's a configuration issue but fall back to defaultLocale when there's a translation issues. Below are the list of errors that we emit out that can be caught during testing:


Issue when we try to format a sentence but some of the placeholder values are malformed, e.g passing in a string for a Date or such.


We trigger this error when a custom format is being declared but there's no corresponding formatter with it. For example:

defaultMessage: 'the price is {p, number, customCurrency}',

and there's no formatter for customCurrency.


When some config values are misconfigured such as missing locale.


When some native Intl APIs don't support certain locales, or missing locale-data when polyfills are setup. This typically happens when you're running on an older browsers/Node, or try to use newer APIs in browsers that have not supported them.


This gets triggered whenever we try to look up a translated message in messages for a given id and it's not there and there is no fallback defaultMessage for the given id.


This error will be triggered very often since it happens for every message that does not have a translation. Therefore if you do log it remotely there should be throttling in place.