webpack.config.js 配置变量

module.exports = {
  mode: 'development',
  plugins: [htmlPlugin],
  module: {
    rules: [
      {
        test: /\.js|jsx$/,
        use: 'babel-loader',
        exclude: /node_modules/
      }
    ]
  },
  resolve: {
    // 省略文件后缀名
    extensions: ['.js', '.jsx', '.json'],
    alias: {
      '@': path.resolve(__dirname, 'src')
    }
  }
}