Webpack - React Router V4 - code splitting duplicate modules in async chunks

Question

The main problem is while code splitting with react-routerV4 and then webpack 2, I have modules that are in several chunks that I can't get to the main one.

My configuration is as follow :

• Webpack 2.2.1
• React-route 4.1.1

I'm using the code splitting as in the react-router v4 documentation

Basically, I don't use the import, but on the route configuration I have : something like this :

import loadHome from 'bundle-loader?lazy&name=home-chunk!./pages/market/Home';
[
  {
    path: url1,
    component: props => <Bundle load={loadHome}>{Home => <Home {...props} />}</Bundle>,
    exact: true,
  },
  // other routes
  ]

This works totally fine with the code splitting and I get a bundle for each route and another bundle for the node_modules that I can later split.

My problem is, I have one node_module (react-slick) that is in several bundles. So I want to get it out in the main bundle.

My webpack configuration is :

module.exports = {
  entry: [
    'whatwg-fetch',
    './src/scripts/index.js',
  ],
  output: {
    path: path.resolve(__dirname, 'src/build'),
    publicPath: '/build/',
    chunkFilename: "[name].js?[hash]",
    filename: '[name].js',
  },
  plugins: [
    new BundleAnalyzerPlugin(),
    new webpack.DefinePlugin({
      'process.env': {
        'NODE_ENV': '"production"'
      }
    }),
    new webpack.optimize.CommonsChunkPlugin({
      name: ['4_node-modules'],
      minChunks(module) {
       const context = module.context;
       return context && context.indexOf('node_modules') >= 0;
      },
    }),
    new webpack.optimize.CommonsChunkPlugin({
      name: ['3_react'],
      chunks: ['4_node-modules'],
      minChunks(module) {
        return module.context && /.*\/react.*/.test(module.context);
      },
    }),
    new webpack.optimize.CommonsChunkPlugin({
        children: true,
        minChunks: 2,
    }),
    new ExtractTextPlugin({
      filename: '[name].css',
      allChunks: true,
    }),
    new HtmlWebpackPlugin({
      filename: '../index.prod.html',
      template: 'src/template.index.prod.html',
      inject: false,
      hash: true,
    }),
  ],
};

According to the documentation, this should do the trick :

new webpack.optimize.CommonsChunkPlugin({
    children: true,
    minChunks: 2,
}),

But nothing happens, I still have "react-slick" in 3 of my bundles.

Does anyone have an hint of what's going on ?

Any help is appreciated :) Thank you !

Answer 1

And I finally got the solution ;)

I let this so it might help someone.

The answer is : Not specifying chunk doesn't apparently target all the chunks but only the last one created.

So let's say with react-router V4 we've created 2 async chunks 'home-chunk' and 'welcome-chunk'. The way to get the common chunks out of it is to add in the webpack config file (in the pluggins):

new webpack.optimize.CommonsChunkPlugin( {
  name : 'common',
  chunks : ['home-chunk', 'welcome-chunk'],
  minChunks : 2,
}),

This will check if there is common modules in the async chunks and if so, put them in the common chunk.