Can't get the JSX preprocessor to run from webpack [duplicate] - reactjs

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This question already has answers here:
Babel file is copied without being transformed
(10 answers)
Closed 6 years ago.
I'm a beginner in React + Webpack.
I found a weird error in my hello world web app.
I'm using babel-loader in webpack to help me convert jsx into js, but it seems like babel can't understand jsx syntax.
Here are my dependencies:
"devDependencies": {
"babel-core": "^6.0.14",
"babel-loader": "^6.0.0",
"webpack": "^1.12.2",
"webpack-dev-server": "^1.12.1"
},
"dependencies": {
"react": "^0.14.1"
}
Here is my webpack.config.js
var path = require('path');
module.exports = {
entry: ['webpack/hot/dev-server',path.resolve(__dirname, 'app/main.js')],
output: {
path: path.resolve(__dirname, 'build'),
filename: 'bundle.js'
},
module: {
loaders: [
{ test: /\.js$/, exclude: /node_modules/, loader: "babel-loader"}
]
}
};
Here is my app/main.js
var React = require("react");
React.render(<h1>hello world</h1>,document.getElementById("app"));
And this is the error message
ERROR in ./app/main.js
Module build failed: SyntaxError: ~/**/app/main.js: Unexpected token (2:13)
1 | var React = require("react");
> 2 | React.render(<h1>hello world</h1>,document.getElementById("app"));
| ^
at Parser.pp.raise (~/**/node_modules/babylon/lib/parser/location.js:24:13)
Thanks for you guys.

Answer 1

Add "babel-preset-react"
npm install babel-preset-react
and add "presets" option to babel-loader in your webpack.config.js
(or you can add it to your .babelrc or package.js: http://babeljs.io/docs/usage/babelrc/)
Here is an example webpack.config.js:
{
test: /\.jsx?$/, // Match both .js and .jsx files
exclude: /node_modules/,
loader: "babel",
query:
{
presets:['react']
}
}
Recently Babel 6 was released and there was a major change:
https://babeljs.io/blog/2015/10/29/6.0.0
If you are using react 0.14, you should use ReactDOM.render() (from require('react-dom')) instead of React.render(): https://facebook.github.io/react/blog/#changelog
UPDATE 2018
Rule.query has already been deprecated in favour of Rule.options. Usage in webpack 4 is as follows:
npm install babel-loader babel-preset-react
Then in your webpack configuration (as an entry in the module.rules array in the module.exports object)
{
test: /\.jsx?$/,
exclude: /node_modules/,
use: [
{
loader: 'babel-loader',
options: {
presets: ['react']
}
}
],
}

Answer 2

I ran into a similar issue when migrating from babel 5 to babel 6.
I was just running babel to compile the src to lib folder babel src --out-dir lib
I will share my setup for babel 6:
Ensure you have the following babel 6 devDependencies installed
"babel-core": "^6.7.6",
"babel-loader": "^6.2.4",
"babel-preset-es2015": "^6.6.0",
"babel-preset-react": "^6.5.0",
"babel-preset-stage-0": "^6.5.0"
Add your .babelrc file to the project:
{
"presets": ["es2015", "stage-0", "react"]
}

Answer 3

Since the answer above still leaves some people in the dark, here's what a complete webpack.config.js might look like:
var path = require('path');
var config = {
entry: path.resolve(__dirname, 'app/main.js'),
output: {
path: path.resolve(__dirname, 'build'),
filename: 'bundle.js'
},
module: {
loaders: [{
test: /\.jsx?$/,
loader: 'babel',
query:
{
presets:['es2015', 'react']
}
}]
},
};
module.exports = config;

Answer 4

For me the solution was to create the file .babelrc with this content:
{
"presets": ["react", "es2015", "stage-1"]
}

Answer 5

The following way has helped me (includes react-hot, babel loaders and es2015, react presets):
loaders: [
{
test: /\.jsx?$/,
exclude: /node_modules/,
loaders: ['react-hot', 'babel?presets[]=es2015&presets[]=react']
}
]

Answer 6

For those who still might be facing issue adding jsx to test fixed it for me
test: /\.jsx?$/,

Answer 7

This works perfect for me
{
test: /\.(js|jsx)$/,
loader: 'babel-loader',
exclude: /node_modules/,
query: {
presets: ['es2015','react']
}
},

Answer 8

You can find a really good boilerplate made by Henrik Joreteg (ampersandjs) here: https://github.com/HenrikJoreteg/hjs-webpack
Then in your webpack.config.js
var getConfig = require('hjs-webpack')
module.exports = getConfig({
in: 'src/index.js',
out: 'public',
clearBeforeBuild: true,
https: process.argv.indexOf('--https') !== -1
})