You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: setup_helper.rb
    path of file: ./repos/rbs/lib/rbs/test
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

mod
    
      def get_sample_size(string)
        case string
        when ""
          DEFAULT_SAMPLE_SIZE
        when 'ALL'
          nil
        else
          int_size = string.to_i
          raise InvalidSampleSizeError.new(string) unless int_size.positive?
          int_size
        end