How to Roll Back a Commit in GitHub?

In software development, mistakes happen—even with version control. Fortunately, Git provides flexible ways to roll back commits, allowing you to correct errors, undo recent changes, or revert to a stable state. This blog post will cover different methods for rolling back commits in Git, including GitHub-specific considerations for a collaborative environment.

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Why Roll Back a Commit?

You might want to roll back a commit in various situations, such as:

• Accidental Commits: Committing a mistake, like debug code or an incomplete feature.
• Errors in Code: Bugs or code issues that need to be removed.
• Unapproved Changes: Committing changes to a shared branch (like main) without approval.

Rolling back commits in Git is relatively simple, but it’s crucial to understand the best method for each situation, especially when working on a shared repository.

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Key Considerations Before Rolling Back a Commit

Before rolling back any commit, keep these points in mind:

1. Determine If Changes Are Pushed: If you haven’t pushed your commits to GitHub yet, rolling back is more straightforward, and you can rework your history without impacting others. If you have pushed your changes to GitHub, proceed with caution to avoid affecting collaborators.
2. Choose the Right Method: Git offers different ways to roll back commits, and each approach serves a different purpose. We’ll cover git reset, git revert, and git checkout, along with when to use each.
3. Collaborate with Your Team: If you’re working with a team, inform them before making changes to shared branches, especially if they involve rewriting commit history.

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Method 1: git reset for Local Commits (History Rewrite)

If you need to roll back a local commit that hasn’t been pushed to GitHub, git reset is ideal. It allows you to rewrite history, making it as though the commit never happened.

How to Use git reset

1. Identify the Commit Hash: Use git log to find the commit hash of the previous commit you want to reset to. For example:

   git log

2. Perform a Hard Reset: If you want to completely discard changes from a commit, use a hard reset. This approach is destructive and will remove all commits after the one specified, along with associated file changes.

   git reset --hard <commit-hash>

• Note: Replace <commit-hash> with the hash of the commit you want to reset to.
• Example: git reset --hard a1b2c3d

1. Push the Changes: If this commit was previously pushed to GitHub, force-push the changes. Be careful with force-pushing, as it changes the shared history and can impact collaborators.

   git push origin <branch-name> --force

When to Use git reset

• For local commits that have not been pushed.
• For situations where you want to completely delete a series of commits.

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Method 2: git revert for Safe Rollbacks (Non-Destructive)

If you’ve already pushed the commit to GitHub, git revert is a safer way to roll back changes. Rather than deleting history, git revert creates a new commit that undoes the changes introduced by a previous commit. This approach keeps the commit history intact and is preferred in collaborative environments.

How to Use git revert

1. Identify the Commit Hash: Use git log to find the hash of the commit you want to revert.

   git log

2. Revert the Commit: Use git revert followed by the commit hash to create a new commit that undoes the changes.

   git revert <commit-hash>

• Git will open a text editor to create a commit message for the revert commit. Modify the message if desired, then save and close.

1. Push the Revert Commit to GitHub: Since git revert doesn’t change the commit history, you can push without force-pushing.

   git push origin <branch-name>

When to Use git revert

• For rolling back specific changes on a branch that has already been pushed to GitHub.
• When you want to preserve the commit history while removing unwanted changes.

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Method 3: git checkout for Temporary Rollbacks

If you want to temporarily go back to a previous commit (for testing or review purposes), you can use git checkout to view an earlier version of your code. This method does not alter your commit history or create new commits.

How to Use git checkout

1. Identify the Commit Hash: Use git log to find the hash of the commit you want to check out.
2. Check Out the Commit: Use git checkout followed by the commit hash. This command will “detach” the head, allowing you to view the state of the code at that commit.

   git checkout <commit-hash>

3. Return to the Branch: When you’re ready to return to the latest version, switch back to the main branch.

   git checkout main

• Note: Avoid making any changes in detached-head mode, as they may be lost unless saved to a new branch.

When to Use git checkout

• For testing a specific state of the code.
• For viewing a previous commit without permanently rolling back changes.

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Method 4: Undoing the Last Commit with git reset HEAD~

If you need to undo just the most recent commit, git reset can roll back one commit without specifying a commit hash.

How to Use git reset HEAD~1

1. Soft Reset: Use a soft reset to keep your changes staged but undo the commit. This will un-commit the changes without discarding them.

   git reset --soft HEAD~1

2. Mixed Reset: If you want to un-commit and unstage the changes, use a mixed reset.

   git reset --mixed HEAD~1

3. Hard Reset: If you want to discard the changes entirely, use a hard reset.

   git reset --hard HEAD~1

4. Push Changes: If this commit has already been pushed to GitHub, use --force when pushing.

   git push origin <branch-name> --force

When to Use git reset HEAD~

• For quickly undoing the last commit.
• For local changes or commits that have not yet been pushed to GitHub.

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Summary of Commands for Rolling Back Commits

Command	Description
git reset --hard <commit-hash>	Deletes commit history and changes up to the specified commit.
git revert <commit-hash>	Creates a new commit that undoes changes from a specific commit.
git checkout <commit-hash>	Temporarily checks out a previous commit without changing history.
git reset --soft HEAD~1	Un-commits the latest commit but keeps changes staged.
git reset --mixed HEAD~1	Un-commits and unstages the latest commit.
git reset --hard HEAD~1	Deletes the last commit and all associated changes.

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Final Notes on Rolling Back Commits

When working with Git and GitHub, it’s essential to choose the right rollback method based on the context:

• Use git reset for local history rewrites that haven’t been pushed.
• Use git revert for remote-safe rollbacks to undo specific commits without disrupting history.
• Inform your team if working in a shared branch before rewriting history with a force-push.

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Conclusion

Rolling back commits in Git and GitHub can seem challenging at first, but with the right commands, it’s straightforward and effective. By using git reset, git revert, and git checkout appropriately, you can manage your commit history, correct errors, and maintain a clean and collaborative codebase.

Whether you’re working on personal projects or collaborating with others, mastering Git’s rollback techniques will make you a more confident and capable developer.