git的撤销与回滚在平时使用中还是比较多的，比如说我们想将某个修改后的文件撤销到上一个版本，或者是想撤销某次多余的提交，都要用到git的撤销和回滚操作。撤销分两种情况，一个是commit之前，一个是commit之后，下面具体看下这两种情况。
一.git commit之前
未添加到暂存区的撤销(没有git add)
添加进暂存区的撤销(git add后)
$ git status
On branch test_git
Changes not staged for commit: 没有添加到暂存区
(use "git add ..." to update what will be committed)
(use "git checkout -- ..." to discard changes in working directory)
modified: test1.php
modified: test2.php
On branch test_git
Changes not staged for commit: 没有添加到暂存区
(use "git add ..." to update what will be committed)
(use "git checkout -- ..." to discard changes in working directory)
modified: test1.php
modified: test2.php
可以通过
git checkout -- filename来撤销修改 git checkout -- test1.php
再次查看文件状态发现选择的文件已经成功被撤销了。
$ git status
On branch test_git
Changes not staged for commit:
(use "git add ..." to update what will be committed)
(use "git checkout -- ..." to discard changes in working directory)
modified: test2.php
On branch test_git
Changes not staged for commit:
(use "git add ..." to update what will be committed)
(use "git checkout -- ..." to discard changes in working directory)
modified: test2.php
如果想将多个文件一次性撤销可以用
git checkout -- .
上面是 未添加到暂存区的撤销
下面是添加到暂存区的
$ git status
On branch test_git
Changes not staged for commit:
(use "git add ..." to update what will be committed)
(use "git checkout -- ..." to discard changes in working directory)
modified: test1.php
modified: test2.php
On branch test_git
Changes not staged for commit:
(use "git add ..." to update what will be committed)
(use "git checkout -- ..." to discard changes in working directory)
modified: test1.php
modified: test2.php
$ git add -A
$ git status
On branch test_git
Changes to be committed: 已经添加暂存区了
(use "git reset HEAD ..." to unstage)
modified: test1.php
modified: test2.php
$ git status
On branch test_git
Changes to be committed: 已经添加暂存区了
(use "git reset HEAD ..." to unstage)
modified: test1.php
modified: test2.php
从暂存区撤销
$ git reset HEAD test1.php
Unstaged changes after reset:
M test1.php
Unstaged changes after reset:
M test1.php
如果想一次性将所有暂存区文件撤销回来，还是上面的命令，不过不用加文件路径。
$ git reset HEAD
Unstaged changes after reset:
M test1.php
M test2.php
Unstaged changes after reset:
M test1.php
M test2.php
二.git commit之后
如果当commit提交后想撤销的话，这就需要revert命令。git revert 命令是撤销某次操作，而在此次操作之前和之后的提交记录都会保留。
先修改了几个文件然后commit 再用git log查看提交记录。
commit 123
Author: jgb
Date: Sat Apr 28 11:21:30 2018 +0800
add content
Author: jgb
Date: Sat Apr 28 11:21:30 2018 +0800
add content
然后使用revert 后面跟上git提交的commitid
git revert 111
Revert "add content"
This reverts commit 111.
# Please enter the commit message for your changes. Lines starting
# with '#' will be ignored, and an empty message aborts the commit.
# On branch test_git
# Changes to be committed:
# modified: test1.php
# modified: test2.php
Revert "add content"
This reverts commit 111.
# Please enter the commit message for your changes. Lines starting
# with '#' will be ignored, and an empty message aborts the commit.
# On branch test_git
# Changes to be committed:
# modified: test1.php
# modified: test2.php
然后在推送到远端更新远程仓库代码，修改的文件就撤销回来了。注意的是revert奇数次生效，偶数次又回到之前的修改状态。比如一个文件内容是a，那么修改为ab，revert后文件变成了a，如果在revert后文件又还原成ab了。
还有就是如果想回到之前某个版本，可以用reset命令，可以回退到某次提交，那该提交之后的提交都会回滚，不过这种覆盖是不可逆的，之前的提交记录都没有了。所以平时开发中尽量注意，避免使用reset。
用法:
git reset --hard commit_id
- --hard – 强制将缓存区和工作目录都同步到你指定的提交
git reset --hard 123
然后在提交到远端覆盖。
来源：原创
发布时间：2021-03-04 20:22:21