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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NUnit

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http://www.nunit.org/

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Toolbox

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Mocking Framework

IsolationInteraction Testing

Rhino Mocks

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Moq

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http://bit.ly/ZHjQQ0

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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: stephen.ritchie@excella.com

• Blog: http://ruthlesslyhelpful.net

• LinkedIn: http://www.linkedin.com/in/sritchie

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