How to undo `hg pull`?

I accidentally did a hg pull 开发者_如何学Pythonand it created a branch in my local repo.

What is the simplest to undo that and get my local repo back to previous state?

hg rollback but beware the caveats:

This command should be used with care. There is only one level of rollback, and there is no way to undo a rollback. It will also restore the dirstate at the time of the last transaction, losing any dirstate changes since that time. This command does not alter the working directory.
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