How to undo local commit

There are several ways to undo the local commit, the most common one is to use the git reset command, which has multiple options to choose from: --soft HEAD^: undo the last commit, keep the modification in the temporary storage area --mixed HEAD^ or --mixed: undo the last commit, modify back to the workspace --hard HEAD^: undo the last commit, discard all modifications. A more advanced way to undo is to use interactive rebase git rebase -i, which allows for more granular control, such as revoking only partial commits or modifying the commit information.

How to undo local commits in Git? This question is awesome!

Many novices, even some veterans, will fall into Git's commit operation. What should you do if you submit it, find that the code is wrong, or the submission information is written incorrectly? Don't panic, Git's powerful undo function can save you from water and fire. After reading this article, you can not only master the method of undoing commit, but also have a deeper understanding of Git's working mechanism to avoid making the same mistakes in the future.

First of all, we need to be clear: Git's undoing is essentially modifying Git's history. This is not as simple as deleting files, it will affect the entire version library. Therefore, it is very important to operate with caution! Backups are always first, especially for important projects.

Basic Review: Understanding commit and HEAD

Git uses commit to record each code modification. Each commit has a unique identifier (SHA-1 hash value). The HEAD pointer points to the latest commit of the current branch. By understanding these two concepts, you will understand that undoing commit is actually modifying the commit pointing to by the HEAD pointer.

Several ways to undo commit

The most common scenario is that you just submitted a commit and immediately find the problem. At this time, you can use the git reset command. This command is very powerful and has a flexible usage, but it is easy to cause problems if you use it poorly, so be careful!

 <code class="bash">git reset --soft HEAD^ # 撤销上一次commit，修改保留在暂存区git reset --mixed HEAD^ # 撤销上一次commit，修改回到工作区(这是默认行为，可以省略--mixed) git reset --hard HEAD^ # 撤销上一次commit，修改全部丢弃</code>

HEAD^ refers to the previous commit, HEAD~2 refers to the previous commit, and so on. --soft retains modification, --mixed (default) modification returns to the workspace, --hard directly discards modification. Which option to choose depends on which modifications you want to keep. I personally usually use --mixed because this allows me to check if the modification is really not needed.

If you want to undo multiple commits, you can do this:

 <code class="bash">git reset --hard HEAD~3 # 撤销最近三个commit</code>

More advanced undo: interactive rebase

If you need more granular control, such as revoking only part of the commit, or modifying the commit information, then git rebase -i command is your weapon. This is a powerful tool that allows you to modify Git's history like editing documents.

 <code class="bash">git rebase -i HEAD~3 # 打开交互式rebase，修改最近三个commit</code>

This opens a text editor that lists the most recent three commits. You can modify the commands for each commit, such as changing pick to edit to modify commit, or changing to squash to merge commit, or even drop a commit. Remember, this operation will modify the history of Git, so be careful! Before using rebase , be sure to make sure your local branch is not pushed by others.

Common Errors and Debugging

• git reset --hard is used too much: this will discard the modifications directly, so be sure to use them with caution. Don't use this option unless you are sure you don't need to modify it.
• Forgot git push --force : If you have pushed the wrong commit, it is not enough to just undo the local commit. You need to force update the remote repository with git push --force . However, this covers the history of the remote repository, so be sure to use it with caution and it is best to avoid it in teamwork. This trick is OK to use in personal projects, so try to avoid teamwork.

Performance optimization and best practices

When committing frequently, using git reset and git rebase will affect efficiency, especially when your project is larger. It is recommended to develop good code submission habits, and keep each commit modification small and independent as much as possible, so that it can be rolled back and undoed easily. Writing clear commit information can also help you better understand the code modification history.

In short, Git's undo is very powerful, but it should also be used with caution. Only by understanding the difference and usage of git reset and git rebase can you better grasp Git and avoid unnecessary trouble. Remember, backup is always the king! Only by practicing more and practicing more can you become a Git master!

The above is the detailed content of How to undo local commit. For more information, please follow other related articles on the PHP Chinese website!