Another git process seems to be running in this repository, e.g. an editor opened by 'git commit'.

切换分支突然git 异常：
Another git process seems to be running in this repository, e.g.
an editor opened by 'git commit'. Please make sure all processes
are terminated then try again. If it still fails, a git process
may have crashed in this repository earlier:
remove the file manually to continue.

意思就是git的进程被另一个占用

解决方案：
进入项目文件夹，显示隐藏文件.git，然后删除index.lock文件即可