lessons from testing

Presented at the excellent Agile On the Beach 2014 conference:

Lessons from Testing from Jon Jagger

some stats on 15,000 practice sessions

As I write this (September 2014) the number of practice dojos on cyber-dojo.org is about 15,000.

The most popular day to run a cyber-dojo is Thursday.

• 1375 Saturday
• 1022 Sunday
• 2488 Monday
• 2588 Tuesday
• 2575 Wednesday
• 2660 Thursday
• 2307 Friday

The most popular language-unit-test framework is Java-JUnit (but the figures probably depend a lot on which ones have been installed the longest).

• 3125 Java JUnit
• 2881 C# NUnit
• 1087 Python unittest
• 1071 C++ assert
• 904 C assert
• 736 PHP PHPUnit
• 701 Javascript assert
• 600 C++ GoogleTest
• 525 Ruby TestUnit
• 384 Python pytest
• 357 Java Approval
• 324 Java Mockito
• 278 C++ CppUTest
• 219 Ruby RSpec
• 217 Java Cucumber
• 205 Javascript jasmine
• 157 Haskell hunit
• 154 Clojure .test
• 131 Go testing
• 125 C++ CATCH
• 120 Perl TestSimple
• ...

The most popular exercise is Fizz Buzz (again, some have been installed longer than others).

• 2091 Fizz Buzz
• 1830 100 doors
• 924 Verbal
• 787 Calc Stats
• 778 Leap Years
• 733 Roman Numerals
• 722 Game of Life
• 713 Anagrams
• 644 Print Diamond
• 549 Tennis
• 498 Prime Factors
• 476 LCD Digits
• 466 Yatzy
• 405 Bowling Game
• 355 Count Coins
• 329 Number Names
• 298 Harry Potter
• 287 Mine Field
• 286 Phone Numbers
• 192 Poker Hands
• ...

terms & conditions

• cyber-dojo is free for non-commercial use.
• Commercial use of the public server requires a license. For example, if you work for a profit-making organization, and you're using https://cyber-dojo.org at work, you need a license.
• The cyber-dojo Foundation issues licenses
• cyber-dojo is provided in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose.

please email us your feedback

What did you like?
What did you dislike?
What should I add?
What should I remove?
Please email your feedback.

how is cyber-dojo implemented?

• cyber-dojo.org runs off a Ruby on Rails server, in a docker container, in a Kubernetes cluster.
• cyber-dojo's languages also run in docker containers.
• cyber-dojo is open sourced and lives on github.
• cyber-dojo was conceived, designed, and implemented by Jon Jagger.
• cyber-dojo's design is strongly influenced by Jerry Weinberg's teachings on experiential learning.

what is cyber-dojo?

• a dojo is a place where martial artists practice martial arts.
• cyber-dojo is where programmers practice programming!
• cyber-dojo is not an individual development environment.
• cyber-dojo is a shared learning environment.
• in a cyber-dojo you focus on improving rather than finishing.
• in a cyber-dojo you practice by going slower.

cyber-dojo tips

• Repeat your practice. Repetition frees up mental capacity creating space for improvement.
  Don't be too concerned about finishing; think about improving.
• cyber-dojo is designed to encourage team practice and works well with two (or more) people at each computer, periodically rotating the current keyboard drivers to different computers as navigators.
• After each practice use the dashboard to start a review. Look for evidence of...
  • starting with a failing test
  • refactoring
  • overly ambitious steps
  • improving the diagnostic
• Practice refactoring.
• Allow at most N amber traffic-lights (total or in-a-row)...
  • per animal
  • per cyber-dojo
  • repeat with reduced value of N
• Turn on traffic-light colour prediction. Allow at most N incorrect predictions...
  • per animal
  • per cyber-dojo
  • repeat with reduced value of N
• Set social challenges...
  • Change keyboard drivers before starting each new practice
  • Change keyboard drivers during a practice
  • Change pairs before starting each new practice
  • Change pairs during a practice
• Set technical challenges...
  • no loops
  • no conditionals
  • no division or modulus
  • immutable data structures only
  • no mouse
  • no data structures
  • maximum 5 lines per method
  • maximum 2 levels of indentation
  • the possibilities are endless!
• When everyone is at green set a challenge to either...
  • find some code you can delete and the tests still all pass
  • find a bug, and write a failing test for it
• Create a custom starting point...
  • with all the tests, but none of the code
  • with all the code, but none of the tests
  • with a specific fault - which pair can fix it first?
• Play the average-time-to-green-game.