一、
sh: /Users/a/Desktop/fltq-sys/node_modules/.bin/vue-cli-service: Permission denied
npm ERR! code ELIFECYCLE
npm ERR! errno 126
npm ERR! vue-element-admin@4.4.0 dev: `vue-cli-service serve`
npm ERR! Exit status 126
npm ERR!
npm ERR! Failed at the vue-element-admin@4.4.0 dev script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
解决方案：在Mac环境下，当复制Vue-cli项目或通过版本工具获取已有项目后，执行命令npm run serve进行调试时，可能会提示XXX/node_modules/.bin/vue-cli-service: Permission denied 权限不足的问题。
chmod 777 node_modules/.bin/vue-cli-service