boolean_test_benchmark.rb

require "benchmark"

CONDITION = false
ONE = 1

Benchmark.bm(30) do |b|
  b.report("if not true") do
    counter = 0
    5_000_000.times { counter += ONE if !CONDITION }
  end

  b.report("unless false") do
    counter = 0
    5_000_000.times { counter += ONE unless CONDITION }
  end
end

__END__

                                    user     system      total        real
if not true                     2.000000   0.010000   2.010000 (  2.019511)
unless false                    1.980000   0.010000   1.990000 (  1.994921)