Test Driven Development Introduction

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Test Driven DevelopmentIntroduction

• Roy Osherove
• Microsoft MVP
• Senior Consultant, Magen
• Agile Development Specialist

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Roy who?

• Agile Development Specialist Magen
• Consultant, Speaker, Writer, Blogger
  ISerializable.com
• Articles, resources ideas and questions
• Contact me Roy_at_Magen.com (or get my card)
• Agile Workshops at Magen
• Check out your flyers
• Starting a new project? Want to go Agile? Not
  sure how? Magen can help.
• And

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Public Announcements

• Agile Israel user group opens!
• All things agile
• Roundtable discussions about problems and
  solutions
• Learning from each other
• Interested? Agile_at_Osherove.com
• Community TDD workshops at Magen
• Get at taste for TDD - Hands on!
• Community as in free!
• 10-12 people at a time
• TDD_at_Osherove.com

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Agenda

• Introduction to TDD
• A simple TDD demo
• The NUnit Framework
• Testing Attributes
• NUnit Addin

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Putting TDD in Context

• Engineering methodologies (waterfall for
  example..)
• Agile (flexible lightwheight) Methodologies
• eXtreme Programming
• Test Driven Development

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The Methodologies

• XP (extreme programming)
• The Crystal family
• MSF(Agile)
• Highsmith's ASD (Adaptive Software Development)
• Scrum
• Feature Driven Development
• DSDM (Dynamic Systems Development Method)
• Rational Unified Process? (dX)

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Test Driven Development

• What is unit testing?
• Why do I want it?
• Whats NUnit?
• Why test first?

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A Unit Test is a testof a small functional piece
of code
Public bool IsLoginOK(string user, string
password) //
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Unit Testing makes your developer lives easier

• Easier to find bugs
• Easier to maintain
• Easier to understand
• Easier to Develop

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You have already done Unit testing

• Not structured
• Not Repeatable
• Not on all your code
• Not easy to do as it should be
• A framework is missing

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The xUnit Frameworks

• Original was for SmallTalk
• Kent Beck and Erich Gamma
• Ported to Various languages and platforms
• JUnit, CppUnit, DUnit, VBUnit, RUnit, PyUnit,
  Sunit, HtmlUnit,
• Good list at www.xprogramming.com
• Standard test architeture
• Introducing NUnit

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How we use NUnit

• Write Tests
• Make it easy to create and organize tests
• Reference an assembly, spread some attributes,
  youre done
• Run Tests
• Allow running all of our tests, a group or just
  one.
• From command line or GUI
• Review Results
• Immediate Pass/Fail feedback
• Details on each failure
• Able to generate XML reports

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The 3A Pattern

• Arrange
• Act
• Assert

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Demo

• Test Structure Example

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NUnit Framework components

• Test Fixtures
• Tests
• Assertions
• Setup
• TearDown
• TestFixtureSetUp
• TestFixtureTearDown

• Ignore
• ExpectedException
• Suites(namespaces)
• Extensibility (new)

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Demo

• Test Attributes

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Test-Driven Development

• Make it Fail
• No code without a failing test
• Make it Work
• As simply as possible
• Make it Better
• Refactor

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Demo

• A simple TDD project

• Add(x,y)
• Zero throws exception
• Can read files with numbers

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Nunit -Addin

• Demo

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Much more to learn

• Database testing
• Mock objects
• Creating customized test cases and suites
  (Extensibility)
• Agile management
• Continuous Integration( managing the build
  process)
• The future VS.NET 2005
• Roy_at_Magen.com

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Embracing TDD in your organization

• You dont have to start big
• Start new tasks with TDD
• Add Tests to code that you need to change or
  maintain but only to small parts.
• Proof of concept Spike Solution
• Growing an architecture
• UML as a communication aid
• Project Handover
• The Architect role (The will to design)

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1/3 Web Siteshttp//www.testdriven.comhttp//www
.xprogramming.comAgileAlliance.com ExtremeProgram
ming.org Blogshttp//dotnetjunkies.com/WebLog/da
rrell_nortonhttp//www.peterprovost.orghttp//we
blogs.asp.net/nunitaddinhttp//weblogs.asp.net/ja
mesnewkirk http//www,iserializable.com
Roy_at_Magen.com
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Refactoring Resources

• 2/3
• Refactoring.com
• http//www.refactoring.com/
• The Father of Refactoring
• http//www.martinfowler.com
• Microsoft Refactoring Developer
• http//weblogs.asp.net/jaybaz_ms/
• C Refactoring Tutorial
• http//geocities.com/bryantrsmith/refactoring/
• Refactoring to Patterns
• http//www.industriallogic.com/xp/refactoring/

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Additional Resources

• 3/3
• Mailing Lists
• Yahoo Group testdrivendevelopment
• Yahoo Group agiledotnet
• Books
• Test-Driven Development in Microsoft .NET James
  Newkirk and Alexei Vorontsov
• Test-Driven Development, by Example Kent Beck
• Test-Driven Development, A Practical Guide
  David Astels
• Unit Testing in Java, Johannes Link

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Questions?

• Roy_at_Magen.com
• www.iserializable.com