csv_bm.rb

# frozen_string_literal: true

require 'benchmark'
require 'benchmark/ips'
require 'benchmark/memory'
require 'csv'

N_NUMBER_OF = 100_000

ary = Array.new(N_NUMBER_OF) { ['one', 'two', 'three', 'four', 'five', 'six'] }
str_ary = Array.new(N_NUMBER_OF) { 'one,two,three,four,five,six' }

Benchmark.ips do |x|
  x.report("CSV lib & csv << row") do
    CSV.open('one.csv', 'wb') do |csv|
      ary.each { |row| csv << row }
    end
  end
  x.report("arr map/to_csv rows") do
    IO.write('two.csv', ary.map(&:to_csv).join)
  end
  x.report("arr map/join rows") do
    IO.write('three.csv', ary.map { |row| row.join(',') }.join("\n"))
  end
  x.report("joined string arr") do
    IO.write('four.csv', str_ary.join("\n"))
  end
  x.compare!
end