运行若依前端(vue2),当npm run dev时,出现如下报错:

C:\Users\Fuck\Desktop\ruoyi-erp-master\ruoyi-erp-master\ruoyi-ui>npm run dev
ruoyi@3.7.0 dev
vue-cli-service serve

 ERROR  Error: Cannot find module '@babel/plugin-proposal-optional-chaining'
Require stack:
- C:\Users\Fuck\Desktop\ruoyi-erp-master\ruoyi-erp-master\ruoyi-ui\node_modules\@babel\core\lib\config\files\plugins.js
- C:\Users\Fuck\Desktop\ruoyi-erp-master\ruoyi-erp-master\ruoyi-ui\node_modules\@babel\core\lib\config\files\index.js
- C:\Users\Fuck\Desktop\ruoyi-erp-master\ruoyi-erp-master\ruoyi-ui\node_modules\@babel\core\lib\index.js
- C:\Users\Fuck\Desktop\ruoyi-erp-master\ruoyi-erp-master\ruoyi-ui\node_modules\@vue\cli-plugin-babel\index.js
- C:\Users\Fuck\Desktop\ruoyi-erp-master\ruoyi-erp-master\ruoyi-ui\node_modules\@vue\cli-service\lib\Service.js
- C:\Users\Fuck\Desktop\ruoyi-erp-master\ruoyi-erp-master\ruoyi-ui\node_modules\@vue\cli-service\bin\vue-cli-service.js
- Did you mean "@babel/plugin-transform-optional-chaining"?

Make sure that all the Babel plugins and presets you are using
are defined as dependencies or devDependencies in your package.json
file. It's possible that the missing plugin is loaded by a preset
you are using that forgot to add the plugin to its dependencies: you
can workaround this problem by explicitly adding the missing package
to your top-level package.json.

解决:

第一步

下载插件（@babel/plugin-proposal-optional-chaining）。

npm install --save-dev @babel/plugin-proposal-optional-chaining

第二步

需在项目里的babel.config.js添加如下代码来拓展解析器。

module.exports = {
  presets: [
  ],
  plugins:[
    ["@babel/plugin-proposal-optional-chaining"]  //解析可选链式语法
  ]
}

第三步

重启项目npm run dev，运行配置。

ok !
​