Relative require times of equivalent syntax

benchmarks.rb

require 'benchmark'
require 'fileutils'
require 'debugger'

def N(&block)
  100_000.times(&block)
end

CASES = {
  'class-definition' => [
    proc{|n| "class A#{n}; end\n"},
    proc{|n| "A#{n} = Class.new{}\n"}
  ],
  'hash-initialization' => [
    proc{"Hash.new\n"},
    proc{"{}\n"}
  ],
}

CASES.each do |name, (case_a, case_b)|
  case_a_file, case_b_file = "#{name}-a.rb", "#{name}-b.rb"
  case_a_file_path, case_b_file_path = "./#{case_a_file}", "./#{case_b_file}"

  File.open(case_a_file, 'w') { |f| N{ |n| f.write(case_a.call(n)) } }
  File.open(case_b_file, 'w') { |f| N{ |n| f.write(case_b.call(n)) } }

  Benchmark.bmbm do |x|
    x.report("Case A: #{name}") do
      fork { require case_a_file_path }
      Process.waitall
    end

    x.report("Case B: #{name}") do
      fork { require case_b_file_path }
      Process.waitall
    end
  end

  FileUtils.rm case_a_file_path
  FileUtils.rm case_b_file_path
end