Exploring Minitest's parallelize_me! option

README.md

Intro

Testing the parallelize_me! option of Minitest.

Without parallelisation

$ ruby parallelisation_test.rb
Run options: --seed 65190

# Running:

....................................................................................................

Finished in 20.306983s, 4.9244 runs/s, 9.8488 assertions/s.

100 runs, 200 assertions, 0 failures, 0 errors, 0 skips

With parallelisation

$ PARALLELIZE=true ruby parallelisation_test.rb
Run options: --seed 22103

# Running:

....................................................................................................

Finished in 10.153597s, 9.8487 runs/s, 19.6975 assertions/s.

100 runs, 200 assertions, 0 failures, 0 errors, 0 skips

Gemfile

source 'https://rubygems.org'

gem 'minitest'

Gemfile.lock

GEM
  remote: https://rubygems.org/
  specs:
    minitest (5.6.1)

PLATFORMS
  ruby

DEPENDENCIES
  minitest

parallelisation_test.rb

require 'bundler/setup'
require 'minitest/autorun'

class ParallelisationTest < Minitest::Test
  parallelize_me! if ENV['PARALLELIZE']

  def setup
    @name = 'bob'
  end

  1.upto(100).each do |count|
    define_method("test_#{count}") do
      assert_equal count, count
      assert_equal 'bob', @name

      sleep 0.2
    end
  end
end