webpack.config.js

const autoprefixer = require('autoprefixer')
const postcss = require('postcss')
const webpack = require('webpack')
const pkg = require('./package.json')
const classPrefix = require('postcss-class-prefix')

const banner = pkg.name + ' v' + pkg.version + ' ' + pkg.homepage

module.exports = {
  devtool: 'source-map',
  entry: './src/index.js',
  devServer: {
    contentBase: './',
    port: 3000
  },
  output: {
    path: __dirname,
    filename: 'eruda-timing.js',
    publicPath: '/assets/',
    library: ['erudaTiming'],
    libraryTarget: 'umd'
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /node_modules|index\.js/,
        use: {
          loader: 'babel-loader',
          options: {
            presets: ['@babel/preset-env'],
            plugins: ['@babel/plugin-transform-runtime']
          }
        }
      },
      {
        test: /\.scss$/,
        loaders: [
          'css-loader',
          {
            loader: 'postcss-loader',
            options: {
              plugins: function() {
                return [
                  postcss.plugin('postcss-namespace', function() {
                    // Add '.dev-tools .tools ' to every selector.
                    return function(root) {
                      root.walkRules(function(rule) {
                        if (!rule.selectors) return rule

                        rule.selectors = rule.selectors.map(function(selector) {
                          return '.dev-tools .tools ' + selector
                        })
                      })
                    }
                  }),
                  classPrefix('eruda-'),
                  autoprefixer
                ]
              }
            }
          },
          'sass-loader'
        ]
      },
      {
        test: /\.hbs$/,
        loader: 'handlebars-loader'
      }
    ]
  },
  plugins: [new webpack.BannerPlugin(banner)]
}