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);
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
I was building an app with expo and ended up with same problem. I fixed this by renaming the import from 'react-native-dotenv'
to '@env'
and then changed my babel.config.js to
module.exports = function(api) {
api.cache(true);
return {
presets: ['babel-preset-expo'],
plugins: [
"module:react-native-dotenv",
]
};
};
I didn't use module:metro-react-native-babel-preset
but if you used it, then I think you need to change the babel.config.js to
module.exports = {
presets: ["module:metro-react-native-babel-preset"],
plugins: [
"module:react-native-dotenv"
]
};
and after these changes, reset the cache of the expo using the following command in the terminal. Mine worked only after this step.
expo r -c