same_all_bench.rb

require 'benchmark'

LEN = 10000
TRY = 1000

s0 = 'x' * 100
s1 = 'x' * 99 + 'y'

cases = {
  shuffle: Array.new(LEN) {|i| i }.shuffle,
  tail0:   [*Array.new(LEN - 1) { s0.dup }, s1],
  head0:   [s1, *Array.new(LEN - 1) { s0.dup }],
  all1:    Array.new(LEN) { s0.dup }
}

class Integer
  def foo
    self * self
  end
end

class String
  alias foo upcase
end

cases.each do |name, ary|
  puts "-" * 40
  puts "Benchmark case: #{name}"

  Benchmark.bm(10) do |x|
    x.report('all?-method-1') do
      TRY.times { ary.all? {|e| e.foo == ary[0].foo } }
    end

    x.report('all?-method-2') do
      TRY.times { ary.empty? || ary[0].foo.yield_self {|e0| ary.all? {|e| e.foo == e0 } } }
    end

    x.report('all?-method-3') do
      TRY.times { ary.empty? || ary[0].foo.yield_self {|e0| ary[1..-1].all? {|e| e.foo == e0 } } }
    end

    x.report('all?-item') do
      TRY.times { ary.all? {|e| e == ary[0] } }
    end

    x.report('opt-method') do
      TRY.times { ary.empty? || ary.map {|e| e.foo }.yield_self {|a| a[0..-2] == a[1..-1] } }
    end

    x.report('opt-item') do
      TRY.times { ary.empty? || ary[0..-2] == ary[1..-1] }
    end
  end

  puts
end