TestDriving ASP'NET Development

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Test-Driving ASP.NET Development

• Tampa Code Camp July 15th, 2006

Cory Foy foyc_at_cornetdesign.com
http//www.cornetdesign.com
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Test-Driving ASP.NET Development

• Session Overview
• Whats this Agile/XP thing?
• Whats this Test-Driven Development thing?
• TDD/NUnit Bowling demo
• Applying TDD to ASP.NET
• Wrap-Up

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Extreme Programming

• Base everything off four principles (the Agile
  manifesto)
• Individuals and Interactions (over processes and
  tools)
• Working Software (over comprehensive
  documentation)
• Customer Collaboration (over contract
  negotiation)
• Responding to change (over following a plan)

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Extreme Programming
http//www.xprogramming.com/xpmag/whatisxp.htm
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Extreme Programming
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Extreme Programming
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Extreme Programming
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Test-Driven Development

• Its about coding
• Its about design
• Way of developing applications by writing tests
• Red-Green-Refactor
• Write a failing test
• Make the test pass by doing the simplest thing
• Refactor duplication

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Test-Driven Development

• NUnit (http//www.nunit.org)

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Test-Driven Development

• Write a test

Watch it fail
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Test-Driven Development

• Make the test pass

• Refactor Duplication

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TDD Bowling Demo

• Create an app to track the score of a bowling
  game
• Consists of 10 frames which can be open frames,
  strikes, spares or bonus rolls
• Scoring is different based on what the type of
  frame is

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Applying TDD to ASP.NET

• NUnitAsp
• http//nunitasp.sourceforge.net
• Extension to NUnit
• Originally created by Brian Knowles, now
  maintained by Jim Shore
• Provides NUnit with the ability to download,
  parse and manipulate ASP.NET pages
• Meant for programmers, not QA teams

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Applying TDD to ASP.NET
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Applying TDD to ASP.NET

• NUnitAsp Drawbacks
• Tests are slow because we are making actual
  requests to IIS
• Information that isnt sent to the client cant
  be tested
• Session and Cache values cant be tested directly

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Applying TDD to ASP.NET

• Model-View-Presenter
• http//www.martinfowler.com/eaaDev/ModelViewPresen
  ter.html
• Separates the behavior of a presentation from the
  view while allowing the view to receive user
  events.
• Make the page as thin as possible and extract
  the logic out to testable classes

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Applying TDD to ASP.NET

• Extract the services you want to provide to an
  interface
• Have your views implement the interface
• Have all interactions between the view and
  controller be through interface exposed methods

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Applying TDD to ASP.NET
http//www.martinfowler.com/eaaDev/ModelViewPresen
ter.html
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Applying TDD to ASP.NET

• ASP.NET MVP demo

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Applying TDD to ASP.NET

• Advantages of Model-View-Presenter in TDD
• Separates your logic from your presentation
• Lets your business logic be tested fast
• Allows mocks of the pages to be built to test
  user behavior
• Easily allows additional views to be plugged in

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Wrap-Up

• Do nothing without frequent feedback
• Testing GUIs is hard but can be mitigated
• Try to make GUI tests (and GUIs) as thin as
  possible

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Wrap-Up

• Links
• http//msdn.microsoft.com/library/en-us/dnvs05/htm
  l/guidelinesfortdd.asp
• http//www.testdriven.com
• http//www.nunit.org
• http//www.testdriven.net (VS plugin)
• http//nunitasp.sourceforge.net
• http//www.cornetdesign.com(presentation)