解决办法：
尝试： 删除 node_modules 文件夹
执行如下命令：
npm cache clean失败。
提示如下：
npm ERR! As of npm@5, the npm cache self-heals from corruption issues and data extracted from the cache is guaranteed to be valid. If you want to make sure everything is cons istent, use 'npm cache verify' instead. On the other hand, if you're debugging an issue with the installer, you can use `npm install --cache /tmp/empty-cache` to use a tempor ary cache instead of nuking the actual one.执行提示命令：
npm install --cache /tmp/empty-cache成功。