hg rollback

roll back the last transaction (dangerous)

    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.

    Transactions are used to encapsulate the effects of all commands that
    create new changesets or propagate existing changesets into a repository.
    For example, the following commands are transactional, and their effects
    can be rolled back:

    - commit
    - import
    - pull
    - push (with this repository as the destination)
    - unbundle

    It's possible to lose data with rollback: commit, update back to an older
    changeset, and then rollback. The update removes the changes you committed
    from the working directory, and rollback removes them from history. To
    avoid data loss, you must pass --force in this case.

    This command is not intended for use on public repositories. Once changes
    are visible for pull by other users, rolling a transaction back locally is
    ineffective (someone else may already have pulled the changes).
    Furthermore, a race is possible with readers of the repository; for
    example an in-progress pull from the repository may fail if a rollback is
    performed.

    Returns 0 on success, 1 if no rollback data is available.

options:

 -n --dry-run do not perform actions, just print output
 -f --force   ignore safety measures

use "hg -v help rollback" to show more info