git pull出现 composer.lock被锁定，即是当前文件不是最新

git fetch origin
git reset –hard origin/master
git pull

Your local changes to the following files would be overwritten by merge

error: Your local changes to the following files would be overwritten by merge:
protected/config/main.php
Please, commit your changes or stash them before you can merge.

解决方法：
- 如果希望保留生产服务器上所做的改动,仅仅并入新配置项, 处理方法如下:
- git stash
- git pull
- git stash pop
然后可以使用git diff -w +文件名来确认代码自动合并的情况.
同样，你也可以使用上述方法直接以线上库为最新代码。