test driven development: blueprint, toolbox, and master craft
DESCRIPTION
Many say that the practice of test driven development (TDD) has the ability to transform software engineering. Let’s break it down from a skeptical pragmatist’s viewpoint. This presentation focuses on three key ideas; the blueprint, the toolbox, and the master craft. Let’s look at TDD as a blueprint for writing code and discuss the implications and benefit. Let’s go beyond the theoretical application of TDD and focus on the toolbox, with examples of what developers need to know to get going. Finally, TDD is a master craft of Agile engineering. To be effective with TDD, let’s look at the progression of skills needed to achieve the promised results of TDD and to maximize its value. Stephen is the organizer of DC Alt.Net (http://bit.ly/ZRDxUj). He frequent speaker and trainer on many .NET topics, including automated testing, continuous integration, code analysis, and .NET best practices.Stephen is the author of the book "Pro .NET Best Practices" (http://amzn.to/v8TD8E).TRANSCRIPT
Stephen D. Ritchie – Managing Consultant – Excella Consulting, Inc., 2300 Wilson Blvd, Suite 630, Arlington, VA 22201 – 703.840.8600 – http://excella.com
Test Driven Development
Stephen RitchieApril 1, 2013
Blueprint, Toolbox, and Master Craft
Stephen D. Ritchie
Live Tweet, Slides and Examples
• Twitter: @RuthlessHelp@Apress
• Slides: http://www.slideshare.net/ruthlesshelp
• Code Samples: http://github.com/ruthlesshelp
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Blueprint
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Toolbox
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Master Craft
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Motivation
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Why test software?
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Motivation
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Blueprint
Red
Refactor Green
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3
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Blueprint
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0. Think1. Write Test Code2. Write Production Code3. RefactorRepeat 12–40+ cycles/hr
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Blueprint
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0. Think
Specification (examples)Consumers (API)Users
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Blueprint
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1. Red
Write a very small amount of test code.
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Blueprint
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2. Green
Write a very small amount of production code.
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Blueprint
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3. Refactor
Improve the code.DesignReadabilityTestability
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Blueprint
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Repeat
Cycle12 to 40+ times per hourKeep it simpleRun all the tests, every time
Software Works
Make Sure
As You Intended
Automated Tests
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But wait …
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Temperature Conversion
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Perhaps an example would
be helpful.
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Temperature Conversion
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Specification By ExampleStart Where You StartDebug As You GoSafely RefactorEngaging (Fun?)
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TDD Katas
• Bowling Score• Roman Numerals• Tennis Score• Conway's Game of Life
• Kata Sites: http://en.wikipedia.org/wiki/Kata_(programming)
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But wait …
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My Manager Wants Me
Slinging Code
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TDD: Quality, Visibility, Etc.
• Focus on Requirements• Clear, Simple, & Testable• Documents Code’s Behavior• Suite of Regression Tests• Enables & Liberates Change• Visibility (KPI)
– Number of Passing Tests– % Code Coverage
• Problem Prevention
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But wait …
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What’s In It For Me?
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TDD: Agility
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http://amzn.to/172CrtT
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TDD: Agility
• Easier Debugging• Personal Process
– Easy to Get Started– Easy to Keep Going
• Detailed Design Do-Overs• What Was I Thinking?
– What Was That Bozo Thinking?
• Hey, Your API Doesn’t Work
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But wait …
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We Have a Boat-Load of Legacy Code
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TDD: Legacy Code
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http://amzn.to/YMpZhl
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TDD: Legacy Code
• Assembly Coverage• Class Coverage• Method Coverage• Branch Coverage• Boundary Analysis• 100% Code Coverage
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Toolbox
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TDD Books
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TDD: Big Picture
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http://amzn.to/10YXE5a
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TDD: The Art
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http://amzn.to/XLOt4b
http://bit.ly/XLOZz0Second Edition:
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Toolbox
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Testing Framework
Run TestsMake Assertions
MSTest
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MBUnit
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xUnit.net
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Toolbox
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Mocking Framework
IsolationInteraction Testing
Rhino Mocks
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Unit Testing
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Perhaps an example would
be helpful.
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The Master Craft
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Continuous Integration
AutomationMonitoring
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CI Servers
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CI in .NET
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http://amzn.to/10mXYIt
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The Master Craft
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Code Coverage
Find Missing TestsMonitoring
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Toolbox
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dotCover
Metrics
http://www.jetbrains.com/dotcover/
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Toolbox
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Open Cover
Metrics
http://nuget.org/packages/OpenCover
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The Master Craft
http://www.ncover.com/
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The Master Craft
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Inversion of Control
Dependency InjectionIoC ContainersMSDN Article: http://bit.ly/172KUxg
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Toolbox
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Autofac
http://code.google.com/p/autofac/
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The Master Craft
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Of Course It’s Safe … After You
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Shameless Self Promotion Time!
• “Best Practices” Initiative• Tips and Tricks• Generate Ideas
– Quantifying Value– Biases & Aversions– Tools & Technologies
• Avoid Making the Same Mistakes Once.
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http://amzn.to/v8TD8E
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Shameless Self Promotion Time!
• 40% off eBook at Apress.comhttp://www.apress.com/9781430240235
• Use promo code: FWUG40
• Offer expires 1-May-2013
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Stephen D. Ritchie
Stephen’s Contact Info
• Twitter: @RuthlessHelp
• Email: [email protected]
• Blog: http://ruthlesslyhelpful.net
• LinkedIn: http://www.linkedin.com/in/sritchie
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