webpack 从指定入口文件中提取公共文件的方法

CommonsChunkPlugin的实现：
entry: {
    index:\'./src/index.js\',
    index1:\'./src/index1.js\',
    index2:\'./src/index2.js\'
},
plugins: [
  new CommonsChunkPlugin({
    name:\"common1\",
    chunks:[\'index\',\'index1\',\'index2\']
  })
]

optimization: {
    splitChunks: {
      chunks:\"all\",
      minSize: 0,
      cacheGroups: {
        common: {
          minChunks: 3,
          priority: -1,
          name:\'common\',
          chunks (chunk) {
            // exclude `my-excluded-chunk`
            return [\'index\',\'index1\',\'index2\'].includes(chunk.name);
          }
        }
      }
    }
  }

new CommonsChunkPlugin({
  name:\"common1\",
  chunks:[\'index\',\'index1\',\'index2\']
}),
new CommonsChunkPlugin({
  name:\"common2\",
  chunks:[\'app\',\'app1\',\'app2\']
}),
new CommonsChunkPlugin({
  name:\"common3\",
  chunks:[\'common1\',\'common2\']
})

optimization: {
    runtimeChunk: \'single\',
    splitChunks: {
      chunks:\"all\",
      minSize: 0,
      cacheGroups: {
        common3: {
         minChunks: 6,
         priority: 1,
         reuseExistingChunk: true
        },
        common2: {
          minChunks: 3,
          priority: -2,
          name:\'common2\',
          chunks (chunk) {
            // exclude `my-excluded-chunk`
            return [\'app\',\'app1\',\'app2\'].includes(chunk.name);
          }

        },
        common1: {
          priority: -1,
          name: \'common1\',
          minChunks: 3,
          enforce: true,
          chunks (chunk) {
            return [\'index\',\'index1\',\'index2\'].includes(chunk.name);
          }
        }
      }
    }
  }