l.js

var path = require("path");
var ExtractTextPlugin = require("extract-text-webpack-plugin");

const ETP = new ExtractTextPlugin({
  allChunks: true
});

module.exports = [
  {
    test: /\.js$/,
    exclude: /node_modules/,
    use: [{
      loader: "babel-loader"
    }]
  },
  {
    test: /\.css$/,
    use: [ { loader: 'style-loader' }, { loader: 'css-loader' } ]
  },
  {
    test: /\.less$/,
    use: ((env) => {
      if(env == 'production') {
        return ETP.extract({         
          use: [{
            loader:'css-loader',
            options: {
              modules: true,
              localIdentName: '[local]--[hash:base64:5]',
            }
          }, {
            loader:'less-loader'
          }]
        });
      }
      else {
        return [{
            loader: 'style-loader'
          }, {
            loader:'css-loader',
            options: {
              modules: true,
              localIdentName: '[local]--[hash:base64:5]',
            }
          }, {
            loader:'less-loader'
          }
        ];
      }
    })(process.env.NODE_ENV)
  },
  {
    test: /\.(ttf|woff|jpeg|jpg|png|gif|svg|woff2|eot)$/,
    use: [
      {
        loader: "file-loader",
        options: {
          outputPath: path.join("assets", "/"),
          name: '[name]--[hash:base64:5].[ext]'
        }
      }
    ]
  }
];