Support for the experimental syntax 'jsx' isn't currently enabled

Javascript Problem Overview

I'm trying to run very simple code, but I'm getting an error, I didn't use the create react app!

It looks like my babel.config.js file is being ignored!

This is the structure of my small project:

My html file

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>ReactJS</title>
</head>

<body>
    <div id="app"></div>
    <script  src = 'bundle.js' ></script>
</body> 

</html>

My index.js file:

import React from 'react';
import { render } from 'react-dom';

render(<h1>Hello World!!</h1>, document.getElementById('app'));

My package json:

{
  "name": "front",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "scripts": {
    "dev": "webpack-dev-server --mode development",
    "build": "webpack-dev-server --mode production"
  },
  "dependencies": {
    "@babel/cli": "^7.10.5",
    "@babel/core": "^7.10.5",
    "@babel/plugin-proposal-class-properties": "^7.10.4",
    "@babel/preset-env": "^7.10.4",
    "@babel/preset-react": "^7.10.4",
    "react": "^16.13.1",
    "react-dom": "^16.13.1",
    "webpack": "^4.43.0",
    "webpack-cli": "^3.3.12",
    "webpack-dev-server": "^3.11.0"
  },
  "devDependencies": {
    "@babel/plugin-transform-runtime": "^7.9.0",
    "babel-loader": "^8.1.0",
    "webpack-dev-server": "^3.10.3"
  }
}

My webpack.config.js

const path = require('path');

module.exports = {
    entry: path.resolve(__dirname, 'src', 'index.js'),
    output: {
        path: path.resolve(__dirname, 'public'),
        filename: 'bundle.js'
    },
    devServer: {
        contentBase: path.resolve(__dirname, 'public'),
    },
    module: {
        rules: [{
            test: /\.js$/,
            exclude: /node_modules/,
            use: {
                loader: 'babel-loader',
            }
        }]
    },
};

And this is my babel.config.js

module.exports = {
    "presets": ["@babel/preset-env", "@babel/preset-react"]

};

Error when

yarn webpack-dev-server --mode development

ERROR in ./src/index.js
Module build failed (from ./node_modules/babel-loader/lib/index.js):
SyntaxError: /root/treina/front/src/index.js: Support for the experimental syntax 'jsx' isn't currently enabled (4:8):

  2 | import { render } from 'react-dom';
  3 | 
> 4 | render(<h1>Hello World!!</h1>, document.getElementById('app'));
    |        ^

Add @babel/preset-react (https://git.io/JfeDR) to the 'presets' section of your Babel config to enable transformation.
If you want to leave it as-is, add @babel/plugin-syntax-jsx (https://git.io/vb4yA) to the 'plugins' section to enable parsing.
    at Parser._raise (/root/treina/front/node_modules/@babel/parser/lib/index.js:757:17)
    at Parser.raiseWithData (/root/treina/front/node_modules/@babel/parser/lib/index.js:750:17)
    at Parser.expectOnePlugin (/root/treina/front/node_modules/@babel/parser/lib/index.js:8849:18)
    at Parser.parseExprAtom (/root/treina/front/node_modules/@babel/parser/lib/index.js:10170:22)
    at Parser.parseExprSubscripts (/root/treina/front/node_modules/@babel/parser/lib/index.js:9688:23)
    at Parser.parseMaybeUnary (/root/treina/front/node_modules/@babel/parser/lib/index.js:9668:21)
    at Parser.parseExprOps (/root/treina/front/node_modules/@babel/parser/lib/index.js:9538:23)
    at Parser.parseMaybeConditional (/root/treina/front/node_modules/@babel/parser/lib/index.js:9511:23)
    at Parser.parseMaybeAssign (/root/treina/front/node_modules/@babel/parser/lib/index.js:9466:21)
    at Parser.parseExprListItem (/root/treina/front/node_modules/@babel/parser/lib/index.js:10846:18)
ℹ ｢wdm｣: Failed to compile.

I'm using yarn and the WSL terminal

Javascript Solutions

Solution 1 - Javascript

Just create a .babelrc file in the root of your project and add:

{
  "presets": ["@babel/preset-env", "@babel/preset-react"]
}

Solution 2 - Javascript

In my case, Creating "babel.config.js" file with the following content worked.

module.exports = {
    presets:[
        "@babel/preset-env",
        "@babel/preset-react"
    ]
}

Solution 3 - Javascript

This https://stackoverflow.com/a/52693007/10952640 solved for me.

You need @babel/preset-react set also on webpack config:

  module: {
    rules: [
      {
        test: /\.(js|jsx)$/,
        exclude: /(node_modules|bower_components)/,
        loader: 'babel-loader',
        options: { presets: ['@babel/env','@babel/preset-react'] },
      },

Solution 4 - Javascript

2021

I fixed it adding

"jsx": "react-jsx"

to my "compilerOptions" on my tsconfig.json file

Solution 5 - Javascript

Yet another possible cause. I got this error when try to run a project in a command prompt at a path that included symlinks. Changing directory directly into the real path solved the issue.

Solution 6 - Javascript

I remade my project from scratch and realized that I was wrong to not include the "D" at the end of the command:

yarn add webpack-dev-server -D

Now it's working!

Solution 7 - Javascript

The solution that worked for me was when I discovered node_modules/react-scripts/config/webpack.config.js contained:

                // @remove-on-eject-begin
                babelrc: false,
                configFile: false,

By setting babelrc: true, I was finally able to get .babelrc changes to work. I'm guessing the configFile: parameter is what you will need to change. (Note, the babelrc appears to need to go into src/ for react-scripts to find it, reasonably likely to also be true for babel.config.js.)

Solution 8 - Javascript

Mmm i think the problem is in your babel, try this:

npm i --save-dev @babel/plugin-proposal-class-properties
add loose:true in your babelrc

Solution 9 - Javascript

inside the webpacker.yml file if using react with rails add jsx extension.

  extensions:
    - .jsx
    - .mjs
    - .js
    - .sass
    - .scss
    - .css
    - .module.sass
    - .module.scss
    - .module.css
    - .png
    - .svg
    - .gif
    - .jpeg
    - .jpg

Solution 10 - Javascript

In my package.json, I added:

 "babel": {
  "presets": [
    "@babel/react",
    "@babel/env"
  ],
  "plugins": [
    "@babel/proposal-class-properties",
    "@babel/plugin-transform-runtime"
  ]
}

Solution 11 - Javascript

For me the test doesn't work in VSCode only. I'm using yarn workspace and CRA as one of the workspaces.

This means the solution is to ignore the failing VSCode tests and start the tests in command line instead:

yarn workspace frontend test

Solution 12 - Javascript

I came across the same error, my problem was that during rebase I lost a brace somewhere so my package.json wasn't working properly - if your babel is showing errors like this - try checking if your package.json has brackets properly set up

Solution 13 - Javascript

For the people who are getting this error while building Remix app, change the extension of file from .js to .jsx/.tsx or check with tsconfig file.

Content Type	Original Author	Original Content on Stackoverflow
Question	Manzini	View Question on Stackoverflow
Solution 1 - Javascript	Mário Prada	View Answer on Stackoverflow
Solution 2 - Javascript	darklord	View Answer on Stackoverflow
Solution 3 - Javascript	BetoLima1	View Answer on Stackoverflow
Solution 4 - Javascript	Lucas Caponi da Silva	View Answer on Stackoverflow
Solution 5 - Javascript	kamrann	View Answer on Stackoverflow
Solution 6 - Javascript	Manzini	View Answer on Stackoverflow
Solution 7 - Javascript	righdforsa	View Answer on Stackoverflow
Solution 8 - Javascript	Ryan Tillaman	View Answer on Stackoverflow
Solution 9 - Javascript	vidur punj	View Answer on Stackoverflow
Solution 10 - Javascript	Thuy	View Answer on Stackoverflow
Solution 11 - Javascript	tonisives	View Answer on Stackoverflow
Solution 12 - Javascript	bstrihova	View Answer on Stackoverflow
Solution 13 - Javascript	purushottam kumar	View Answer on Stackoverflow