array_concat_vs_push.rb

require 'benchmark'
 
def many
  10000
end
 
def push(left_array_size, right_array_size)
  left = Array.new(left_array_size) { |n| n }
  right = Array.new(right_array_size) { |n| n }
  Benchmark.realtime{ many.times{ |i| left.push(*right) } }
end
 
def concat(left_array_size, right_array_size)
  left = Array.new(left_array_size) { |n| n }
  right = Array.new(right_array_size) { |n| n }
  Benchmark.realtime{ many.times{ |i| left.concat(right) } }
end

puts *Object.constants.grep(/RUBY/).map { |c| Object.const_get(c) }

0.step(1000, 50) do |n|
  puts "Array Size: #{n}"
  puts "Push:       #{push(n, n)}"
  puts "Concat:     #{concat(n, n)}"
  puts
end