vue项目报错Cannot assign to read only property ‘exports‘ of object ‘Object‘

vue项目报错Cannot assign to read only property ‘exports’ of object ‘Object’，原因是commonJS和ES6的语法混用导致的

解决办法
安装 transform-es2015-modules-commonjs

npm install transform-es2015-modules-commonjs

修改babel的配置文件，添加plugin