# File lib/ruby-progressbar/outputs/non_tty.rb, line 18
  def bar_update_string
    formatted_string        = bar.to_s
    formatted_string        = formatted_string[0...-1] unless bar.finished?

    output_string           = formatted_string[last_update_length..-1]
    self.last_update_length = formatted_string.length

    output_string.to_s
  end