在vue.config.js中怎么配置将一个第三方库编译成es5

Question

const path = require('path');

function resolve(dir) {

return path.join(__dirname, dir);

}

module.exports = {

publicPath: '/wf/',
chainWebpack(config) {}
configureWebpack: {
    devtool: 'source-map'
},
css: {},
productionSourceMap: true,
devServer: {
    compress: true,
    port: 9000,
    proxy: {}
},

};