Intl.RelativeTimeFormat is undefined even if jscFlavor includes intl

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Description

console.log(Intl.RelativeTimeFormat) outputs undefined even if I define in my app/build.gradle the jscFlavor = 'org.webkit:android-jsc-intl:+'. The jscFlavor partially works because I can use the Intl.DateTimeFormat with some options that weren’t working before the flavor change.

React Native version:

0.63.2

Expected Results

Intl.RelativeTimeFormat should be usable

[podenborg]

For anyone else having this issue, I was able to get it to work by installing the following poyfills: yarn add @formatjs/intl-locale @formatjs/intl-relativetimeformat

And then in the entry point for my app I added the following:

import { registerRootComponent } from 'expo'
import { Platform } from 'react-native'
import App from './App'

if (Platform.OS === 'android') {
  require('@formatjs/intl-locale/polyfill')
  require('@formatjs/intl-relativetimeformat/polyfill')
  require('@formatjs/intl-relativetimeformat/locale-data/en') // locale-data for en
}

registerRootComponent(App)

You will need to follow these steps after you change the jsc flavor in the app gradle to use the 'org.webkit:android-jsc-intl:+' flavor.

[cortinico]

Thanks for sharing @podenborg

Closing as a workaround was suggested 👍