Documentation for read option of Collection#find is incorrect

@option opts [:primary, :secondary] :read The default read preference for queries

    #   initiates from this connection object. If +:secondary+ is chosen, reads will be sent

    #   to one of the closest available secondary nodes. If a secondary node cannot be located, the

    #   read will be sent to the primary. If this option is left unspecified, the value of the read

    #   preference for this Collection object will be used.

database['some_collection'].find({},{read: {mode: :secondary}}).first

NoMethodError: undefined method `select_server' for {"mode"=>:secondary}:BSON::Document