Nathaniel Neitzke Lighthouse1, LLC [email protected].
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Transcript of Nathaniel Neitzke Lighthouse1, LLC [email protected].
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 – ObservationGiven [Context] When [Action] Then
[Observation]
FormatTitle (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
http://dannorth.net/introducing-bdd http://dannorth.net/whats-in-a-story
RSpec http://rspec.info/
Cucumber http://cukes.info/
IronRuby http://www.ironruby.net/
Beyond Test Driven Development Video http://video.google.com/videoplay?docid=8135690990081075324
The RSpec Book: BDD with RSpec, Cucumber, etc.. http://www.pragprog.com/titles/achbd/the-rspec-book
Questions?
