webpack.config.js

const path = require('path')
const VueLoaderPlugin = require('vue-loader/lib/plugin')

module.exports = {
  devtool: 'cheap-module-source-map',
  entry: './src/index.js',
  output: {
    path: path.resolve(__dirname, './dist/'),
    filename: 'index.js',
    library: 'vue-cropper',
    libraryTarget: 'umd',
    umdNamedDefine: true
  },
  resolve: {
    extensions: ['.js', '.vue'],
    alias: {
      'vue$': 'vue/dist/vue.common.js'
    }
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /(node_modules|bower_components)/,
        use: {
          loader: 'babel-loader',
          options: {
            presets: ['@babel/preset-env'],
            plugins: ['@babel/transform-runtime']
          }
        }
      },
      {
        test: /\.vue$/,
        loader: 'vue-loader'
      },
      {
        test: /\.css$/,
        use: [
          'style-loader',
          'css-loader'
        ]
      }
    ]
  },
  mode: "production",
  plugins: [
    // 请确保引入这个插件！
    new VueLoaderPlugin()
  ]
}