I executed the following line:
git rebase -i dev --onto master
I figured this would cut my dev branch and paste it on top of my master branch. And the -i would let me collapse the changesets.
But when it brought up the editor, I did not see any of the changesets. All I saw was "noop". So I just exited it. And then I look at my git history, all my changes are gone. My dev branch is at the same place my master is at!
Can some one help me recover? Thanks!