How to Undo Changes in Git?

In the world of version control, Git offers a range of powerful tools for tracking, managing, and revisiting changes to your codebase. However, when things go wrong, knowing how to undo changes in Git can be a lifesaver. Whether you need to reverse recent changes, unstage a file, or even amend your latest commit, Git provides multiple ways to get your project back on track.

In this blog, we’ll walk through various techniques to undo changes in Git with detailed explanations and examples.

Why Would You Need to Undo Changes?

There are several common scenarios where you might want to undo changes in Git:

1. Accidental Changes: You committed changes you didn’t intend to or used the wrong message.
2. Unwanted File Staging: You added files to the staging area by mistake.
3. Reverting to a Previous State: You need to go back to a known stable version due to new bugs or errors.
4. Removing Recent Commits: You want to delete or alter recent commits.

Understanding how to reverse these actions is essential for effective code management, especially in collaborative environments.

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Common Commands for Undoing Changes in Git

Here’s a breakdown of some commonly used commands in Git for undoing changes:

• Unstaging Changes: git restore --staged <file>
• Discarding Local Changes: git restore <file>
• Reverting Commits: git revert <commit>
• Undoing the Last Commit: git reset --soft HEAD~1 or git reset --hard HEAD~1
• Amending the Last Commit: git commit --amend

Let’s look at each of these commands in detail.

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1. Unstaging Changes with git restore --staged

If you accidentally added a file to the staging area (using git add), you can easily unstage it without deleting any actual code.

git restore --staged <file>

For example, if you staged a file called example.txt but aren’t ready to commit it yet:

git restore --staged example.txt

This command removes example.txt from the staging area but keeps the changes in your working directory.

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2. Discarding Local Changes with git restore

If you want to discard changes in a specific file and return it to the last committed version:

git restore <file>

For example, to discard changes in example.txt:

git restore example.txt

Warning: This command is irreversible—you will lose any changes made to the file that haven’t been committed.

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3. Undoing Changes in the Working Directory with git checkout

If you need to revert all files in your working directory back to the last commit, you can use:

git restore .

Or, in older versions of Git:

git checkout -- .

This command will discard all uncommitted changes across all files, returning the working directory to the state of the last commit.

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4. Reverting a Commit with git revert

If you want to undo a specific commit but keep your commit history intact, git revert is the way to go. This command creates a new commit that undoes the changes from a specified commit.

git revert <commit>

To find the commit hash, you can use:

git log

Then, copy the hash of the commit you want to undo and run:

git revert <commit-hash>

Git will create a new commit that reverses the changes introduced in the specified commit, making it ideal for undoing changes on shared or collaborative branches.

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5. Undoing the Last Commit with git reset

If your last commit was a mistake, you can use git reset to undo it. There are three main types of resets:

• --soft: Keeps changes in the staging area.
• --mixed: Unstages changes but keeps them in the working directory.
• --hard: Discards changes completely.

Soft Reset

A soft reset is useful if you want to change the previous commit without losing any changes:

git reset --soft HEAD~1

This will undo the last commit and keep the changes in the staging area, allowing you to re-commit or make additional modifications.

Mixed Reset

If you want to unstage the last commit but leave the changes in the working directory:

git reset --mixed HEAD~1

This command removes the commit and moves the changes back to your working directory, so you can make further edits or stage files selectively.

Hard Reset

A hard reset should be used cautiously, as it discards all changes:

git reset --hard HEAD~1

This command permanently deletes the last commit and any associated changes in your working directory. It’s ideal when you want a completely fresh start but may lead to data loss if not used carefully.

Warning: Avoid using --hard reset on shared branches, as it rewrites history and can affect other collaborators.

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6. Amending the Last Commit with git commit --amend

If you need to fix a typo in your last commit message or add a file you forgot to include, git commit --amend is helpful:

git commit --amend

When you run this command, Git opens the commit message editor, allowing you to modify the message or add new staged changes to the last commit.

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7. Deleting Untracked Files with git clean

To remove untracked files from your working directory, you can use git clean:

git clean -f

Use -fd to delete untracked directories as well:

git clean -fd

Warning: git clean permanently deletes files. Use it cautiously, especially if there are untracked files you may want to keep.

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Summary of Commands

Action	Command	Description
Unstage a file	git restore --staged <file>	Removes a file from staging.
Discard changes to a file	git restore <file>	Reverts changes to the last commit version.
Revert a commit	git revert <commit>	Creates a new commit that undoes changes from a specific commit.
Undo the last commit (soft)	git reset --soft HEAD~1	Keeps changes in the staging area.
Undo the last commit (mixed)	git reset --mixed HEAD~1	Keeps changes in the working directory.
Undo the last commit (hard)	git reset --hard HEAD~1	Discards changes completely.
Amend the last commit	git commit --amend	Updates the last commit with new changes or message.
Remove untracked files	git clean -f	Deletes untracked files in the directory.

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Conclusion

Understanding how to undo changes in Git is essential for efficient version control. From staging mistakes to modifying commit history, Git provides robust tools to help you manage and reverse your work when necessary. While commands like git reset and git clean are powerful, using them cautiously and with a clear understanding of their implications is crucial, especially when working on collaborative projects. Mastering these commands will make you a more proficient developer and help you keep your codebase clean and organized.