Recovering lost commits with reflog in Git - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

What is the output of git reflog after a commit reset?

You ran git reset --hard HEAD~1 to undo the last commit. What will git reflog show as the latest entry?

Git

git reset --hard HEAD~1
git reflog

A HEAD@{0}: merge: moving to HEAD~1

B HEAD@{0}: commit: Undo last commit

C HEAD@{0}: checkout: moving to HEAD~1

D HEAD@{0}: reset: moving to HEAD~1

💡 Hint

Think about what git reset --hard does to the HEAD pointer.

After git reset --hard HEAD~1, the HEAD moves to the previous commit. The reflog records this as a reset action, so the latest entry is reset: moving to HEAD~1.

🧠 Conceptual

intermediate

Which command recovers a lost commit using reflog?

You accidentally lost a commit after a reset. Which command correctly restores the lost commit using reflog?

A git revert HEAD@{1}

B git checkout HEAD@{1}

C git reset --hard HEAD@{1}

D git merge HEAD@{1}

💡 Hint

You want to move HEAD back to the lost commit forcibly.

git reset --hard HEAD@{1} moves the HEAD pointer back to the previous state recorded in reflog, restoring the lost commit.

❓ Troubleshoot

advanced

Why does git reset HEAD@{2} fail to restore a lost commit?

You tried git reset HEAD@{2} to recover a lost commit but it did not work as expected. What is the most likely reason?

A HEAD@{2} is not a valid reflog entry

B It does not use the <code>--hard</code> flag, so working directory and index are not updated

C You need to use <code>git revert</code> instead of reset

D The reflog only tracks branches, not commits

💡 Hint

Consider what git reset does by default without flags.

By default, git reset without --hard only moves HEAD and updates the index but does not change the working directory. To fully restore a lost commit state, --hard is needed.

🔀 Workflow

advanced

Order the steps to recover a lost commit using reflog

Arrange the steps in the correct order to recover a lost commit using reflog.

A 1,2,3,4

B 2,1,3,4

C 3,1,2,4

D 1,3,2,4

💡 Hint

Think about finding the commit first, then restoring it, then verifying.

First, find the lost commit in reflog. Then reset hard to that commit. Next, verify with git log. Finally, check your files.

✅ Best Practice

expert

What is the safest way to recover a lost commit without risking current work?

You want to recover a lost commit using reflog but keep your current changes safe. Which approach is best?

A Create a new branch at the lost commit using 'git branch recover HEAD@{1}'

B Run 'git reset --hard HEAD@{1}' directly to restore the commit

C Use 'git checkout HEAD@{1}' to switch to the lost commit detached HEAD

D Run 'git revert HEAD@{1}' to undo changes

💡 Hint

Think about preserving your current work and avoiding forced resets.

Creating a new branch at the lost commit preserves your current work and allows you to inspect or merge changes safely without resetting your current branch.