Webpack with react modules giving unexpected token

Question

Been trying to use the react-spin npm module, but when I try and build a bundle.js with webpack, I receive the following error:

Module parse failed: /Users/nir/browsewidget/node_modules/react-spin/src/main.js Line 29: Unexpected token <
You may need an appropriate loader to handle this file type.
|   render: function() {
|     return (
|       <span ref="container" />
|     );
|   }
 @ ./js/widget.jsx 4:14-35

I am guessing that this module has jsx in it, but I don't understand why it can't be built? Does react-spin need some extra configuration when building a bundle?

Here is my full webpack.config.js:

module.exports = {
    entry: "./js/widget.jsx",
    output: {
        path: __dirname,
        filename: "bundle.js"
    },
    module: {
        loaders: [
            {
                    test: /\.jsx$/, 
                    loader: 'jsx-loader?insertPragma=React.DOM&harmony'
            }
        ]
    },
    externals: {
        //don't bundle the 'react' npm package with our bundle.js
        //but get it from a global 'React' variable
        'react': 'React'
    },
    resolve: {
        extensions: ['','.js','.jsx']
    }
};

Answer 1

Your loader is configured to only transform files that end in .jsx:

 test: /\.jsx$/,

(The dollar sign means end-of-string.)

You could change it to

test: /\.jsx?$/,

to transform both .js and .jsx files, but running every JavaScript file in node_modules through the JSX loader will probably be fairly slow.

I believe you should be able to set an exclude option of /node_modules/ and then an include option for the specific module you care about (react-spin), but the best solution is that packages not use JSX in the published version of the JavaScript—the author of react-spin might be open to a pull request to this effect. (Edit: it appears there already is one, see thomasboyt/react-spin#3)

Finally, react-spin is very small, so you man consider implementing it yourself in your own project (so that you don't have to worry about the webpack loader issues).