我有同样的错误，当我部署时我有这个警告:

I had the same error, when i deployed i had this warning:

⚠ 函数:您必须有一个 firebase-functions 版本，该版本位于至少 2.0.0.请运行 npm i --save firebase-functions@latest 在函数文件夹.

⚠ functions: You must have a firebase-functions version that is at least 2.0.0. Please run npm i --save firebase-functions@latest in the functions folder.

在我安装了它工作的最后一个 firebase-functions 版本之后.

after i installed the last firebase-functions version it worked.

所以我的解决方案是:

npm i --save firebase-functions@latest

npm i --save firebase-functions@latest