How to undo git stash pop

git stash is a tool in Git that temporarily shelves (or stashes) changes you've made to your working directory allowing you to work on something else, and then come back and re-apply them later on. However, sometimes after running git stash pop, you might realize that you either need to undo this action or manage unexpected conflicts. This guide explores how to effectively undo a git stash pop.

Understanding git stash pop

When you execute git stash pop, Git attempts to reapply the changes stashed most recently and then removes the stashed changes from the stash list. This operation is risky in that it automatically attempts to clear the stash once the pop is complete, which can complicate attempts to undo it if something goes wrong.

Does git stash pop overwrite changes?

git stash pop will attempt to merge stashed changes back into your working directory. If there are no conflicts, it will successfully apply the changes. If conflicts arise, Git will stop the process for you to manually resolve them, but the stash will not automatically be removed if conflicts prevent the stash from being fully applied.

How to undo git stash pop

Undoing a git stash pop involves several steps, depending on what exactly you need to reverse or recover:

Scenario 1: Reverting changes after a successful stash pop

If git stash pop was successful and you want to revert the changes it made, you can use:

git reset --hard

This command resets the working directory to the last commit state, erasing all changes made since. However, it’s crucial to understand that this method is destructive to any uncommitted changes in your working directory.

Scenario 2: Recovering the stash after it has been popped

If you need to get the stash back because you popped it accidentally then discarded those changes you can:

1. Check if Git still has a reference to the stash commit:

   Terminal

   git fsck --no-reflog | grep stash
   
   

2. If you find a stash commit (something like dangling commit xyz123), you can inspect it:

   Terminal

   git stash show -p xyz123
   
   

3. If this is the stash you lost, apply it again:

   Terminal

   git stash apply xyz123
   
   

This will recover the stashed changes and apply them to your working directory.

Scenario 3: Resolving conflicts after a stash pop

If you popped the stash and encountered conflicts, Git will not remove the stash from the stash list. In this case:

1. Resolve the conflicts as you would after a merge conflict.
2. Decide whether to keep the stash:
   • If you want to keep the stash, simply leave it in the stash list.
   • If you no longer need the stash, run git stash drop to remove it once you're satisfied with the conflict resolution.

Scenario 4: Using reflog to revert changes

The git reflog can also be a helpful tool if you've lost track of what has happened after various operations:

git reflog

Look for entries related to stash application, and reset your branch to a point before the stash was popped:

git reset --hard HEAD@{n}

Where n is the index in the reflog before the stash was applied.

For further reading on this subject see "Every engineer should understand git reflog".

Undoing a git stash pop can be complex, especially if conflicts are involved or if the stash was removed successfully. Regularly committing changes or using git stash apply instead of git stash pop (which doesn't remove the stash) can provide more flexibility and reduce the need for complex recovery operations. By understanding these techniques, you can better manage your Git stashes and recover from mistakes more effectively.

For further reading on undoing a git stash pop see the official Git documentation.