git push code Push to origin/master was rejected

• 没办法push，尝试先 pull 一下代码，提示如下错误

Git Pull Failed
POST git-upload-pack (225 bytes)
remote: Enumerating objects: 4, done.
remote: Total 4 (delta 0), reused 0 (delta 0), pack-reused 0
warning: no common commits
From "project git url"
* branch            master     -> FETCH_HEAD
* [new branch]      master     -> origin/master
refusing to merge unrelated histories

• 解决方法，使用如下命令，将 git 上的代码及文件拉取到本地，然后再 push

git pull origin master --allow-unrelated-histories