How can I undo git reset --hard HEAD~1?

Question

Is it possible to undo the changes caused by the following command? If so, how?

git reset --hard HEAD~1

Answer 1

What you want to do is to specify the sha1 of the commit you want to restore to. You can get the sha1 by examining the reflog (git reflog) and then doing

git reset --hard

But don't wait too long... after a few weeks git will eventually see that commit as unreferenced and delete all the blobs.