Benchmarking Ruby's monkey patch vs alias method vs conventional ways to test Array content.

benchmark_alias_monkey_patch.rb

#! /usr/bin/env ruby

require 'benchmark'

class Array
  def blank?
    empty?
  end

  alias :blankk? :empty?
end

class NilClass
  def blank?
    true
  end

  alias :blankk? :nil?
end

array = []
10_000_000.times do
  case rand(3)
  when 0 then array << nil
  when 1 then array << []
  else array << [*(0..(rand(50)))]
  end
end

just = 20

Benchmark.bm do |x|
  x.report('with_proc_notation'.ljust(just))   { array.count(&:blankk?)                       }
  x.report('with_alias'.ljust(just))           { array.count { |a| a.blankk?                } }
  x.report('with_nil?_and_empty?'.ljust(just)) { array.count { |a| a.nil?   || a.empty?     } }
  x.report('with_monkey_patch'.ljust(just))    { array.count { |a| a.blank?                 } }
  x.report('with_just_nil?'.ljust(just))       { array.count { |a| a.nil?   || a.count == 0 } }
  x.report('with_just_empty?'.ljust(just))     { array.count { |a| a == nil || a.empty?     } }
  x.report('C-like'.ljust(just))               { array.count { |a| a == nil || a.count == 0 } }
  x.report('with_any?'.ljust(just))            { array.count { |a| a == nil || !a.any?      } }
end

# RESULT (in seconds, sorted from fastest to slowest)
#                       user       system     total       real
# with_proc_notation    0.800000   0.000000   0.800000 (  0.810540)
# with_alias            1.020000   0.000000   1.020000 (  1.027987)
# with_nil?_and_empty?  1.080000   0.000000   1.080000 (  1.080706)
# with_monkey_patch     1.180000   0.010000   1.190000 (  1.183125)
# with_just_nil?        1.270000   0.000000   1.270000 (  1.278921)
# with_just_empty?      1.510000   0.010000   1.520000 (  1.510084)
# C-like                1.760000   0.000000   1.760000 (  1.758057)
# with_any?             2.110000   0.000000   2.110000 (  2.118271)
#
# with_proc_notation    0.720000   0.010000   0.730000 (  0.732619)
# with_alias            0.960000   0.000000   0.960000 (  0.964733)
# with_nil?_and_empty?  1.030000   0.000000   1.030000 (  1.028848)
# with_monkey_patch     1.080000   0.000000   1.080000 (  1.083973)
# with_just_nil?        1.230000   0.000000   1.230000 (  1.248339)
# with_just_empty?      1.480000   0.010000   1.490000 (  1.486006)
# C-like                1.780000   0.000000   1.780000 (  1.785834)
# with_any?             2.160000   0.000000   2.160000 (  2.173112)
#
# with_proc_notation    0.740000   0.000000   0.740000 (  0.749683)
# with_alias            0.990000   0.000000   0.990000 (  1.003299)
# with_nil?_and_empty?  1.130000   0.010000   1.140000 (  1.164617) v
# with_monkey_patch     1.080000   0.010000   1.090000 (  1.082769) ^
# with_just_nil?        1.270000   0.000000   1.270000 (  1.288284)
# with_just_empty?      1.510000   0.010000   1.520000 (  1.514877)
# C-like                1.750000   0.010000   1.760000 (  1.755909)
# with_any?             2.070000   0.000000   2.070000 (  2.065673)