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Unknown Option error from Babel in React-Native app

I am building a react-native app with typescript in order to learn react native. Once I run the app with expo start and try to run on emulator I get this error:

index.js: [BABEL] ......../index.js: Unknown option: .name. Check out https://babeljs.io/docs/en/babel-core/#options for more information about options

Actually I didn’t have this error before. I tried to install react-native-dotenv package and while doing it installed metro-react-native-babel-preset too, which I am not sure whether was already installed or not.

My package.json is as follows:

{
 "name": "mobile-app",
 "version": "0.0.1",
 "private": true,
 "scripts": {
   "android": "react-native run-android",
   "ios": "react-native run-ios",
   "start": "react-native start",
   "test": "jest",
   "lint": "eslint . --ext .js,.jsx,.ts,.tsx"
 },
 "dependencies": {
   "@react-native-community/async-storage": "^1.12.0",
   "@react-native-community/google-signin": "^4.0.3",
   "@types/axios": "^0.14.0",
   "axios": "^0.20.0",
   "expo": "^38.0.10",
   "react": "16.13.1",
   "react-native": "0.62.2"
 },
 "devDependencies": {
   "@babel/core": "^7.8.4",
   "@babel/runtime": "^7.8.4",
   "@react-native-community/eslint-config": "^1.1.0",
   "@types/jest": "^25.2.3",
   "@types/react-native": "^0.63.2",
   "@types/react-native-dotenv": "^0.2.0",
   "@types/react-test-renderer": "^16.9.2",
   "@typescript-eslint/eslint-plugin": "^2.27.0",
   "@typescript-eslint/parser": "^2.27.0",
   "babel-jest": "^25.1.0",
   "eslint": "^6.5.1",
   "jest": "^25.1.0",
   "react-native-clean-project": "^3.4.0",
   "react-native-dotenv": "^2.4.1",
   "react-test-renderer": "16.13.1",
   "typescript": "^3.8.3"
 },
 "jest": {
   "preset": "react-native",
   "moduleFileExtensions": [
     "ts",
     "tsx",
     "js",
     "jsx",
     "json",
     "node"
   ]
 }
}

babel.config.js :

module.exports = {
  presets: ['module:metro-react-native-babel-preset', 'module:react-native-dotenv'],
};

index.js

/**
 * @format
 */

import { AppRegistry } from 'react-native';
import App from './App';
import { name as appName } from './app.json';

AppRegistry.registerComponent('main', () => App);

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Answer

Turns out that the issue was related to react-native-dotenv settings. Changed babel.config.js to :

module.exports = {
  presets: ['module:metro-react-native-babel-preset'],
  plugins: [
    ["module:react-native-dotenv", {
      "moduleName": "@env",
      "path": ".env",
      "blacklist": null,
      "whitelist": null,
      "safe": false,
      "allowUndefined": true
    }]
  ]
};

Also changed the import statement from: import {VARIABLE} from "react-native-dotenv" to: import {VARIABLE} from "@env"

Credit for the solution:
https://github.com/facebook/react-native/issues/29314
Solution:
https://github.com/goatandsheep/react-native-dotenv/wiki/Migration-Guide

User contributions licensed under: CC BY-SA
6 People found this is helpful
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