Nathaniel Neitzke Lighthouse1, LLC

Test driven development Where did it come from? What is it?

Why automated tests?  To verify correctness?

Confidence  Ability to change

Isolation  Debugging is hard, time consuming

Design  BDUF  Goldplating

Documentation  What does this code do?

Testability  Send quality code to QA

So what’s wrong with tdd?  Focus on tests so it must be testing right?  Sapir-Whorf

The problem with “unit”  What is a unit?  Unit test -> class

Programmers think…  I’m not going to write all those tests  It’s really simple code, it doesn’t need to be tested  Testing is a waste of time  I’ve done this all a million times (loops, data retrieval, functionality, etc…)

Manager’s think…  We test after the code is done  That’s what we have a testing person for  We can’t spend that time now

Behavior driven development  TDD done very well  Not about tests  Think differently  Dan North/Aslak Hellesøy 2004

Specifications  Executable specifications around the behavior of your system

User stories  Conversation between customer and developer  Drive our executable specifications  Role, feature, benefit As a [role] I want [feature] so that [benefit]

Scenarios  Detail acceptance criteria for a particular user story  Context – Action – Observation Given [Context] When [Action] Then [Observation]

Format Title (one line describing the story) Narrative: As a [role] I want [feature] So that [benefit] Acceptance Criteria: (presented as Scenarios) Scenario 1: Given [context] And [some more context]… When [event] Then [outcome] And [another outcome]…. Scenario 2: ….

rspec & cucumber  Frameworks/Tools

DEMO

.NET Frameworks  NBehave, .NETSpec  Machine.Specifications

Other Tools  TextMate/e  Autotest  Heckle  Rake  RCov

Resources  Dan North  RSpec  Cucumber  IronRuby  Beyond Test Driven Development Video  The RSpec Book: BDD with RSpec, Cucumber, etc..

Questions?