Setting Up webpack-merge

安裝 webpack-merge：

npm i webpack-merge --save-dev

設定 webpack.config.js：

const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');

const merge = require('webpack-merge');


const PATHS = {
  app: path.join(__dirname, 'app'),
  build: path.join(__dirname, 'build')
};


//module.exports = {  // 刪除這行


const common = {

  // Entry accepts a path or an object of entries.
  // We'll be using the latter form given it's
  // convenient with more complex configurations.
  entry: {
    app: PATHS.app
  },
  output: {
    path: PATHS.build,
    filename: '[name].js'
  },
  plugins: [
    new HtmlWebpackPlugin({
      title: 'Webpack demo'
    })
  ]
};

var config;

// Detect how npm is run and branch based on that
switch(process.env.npm_lifecycle_event) {
  case 'build':
    config = merge(common, {});
    break;
  default:
    config = merge(common, {});
}

module.exports = config;