Unit Testing 101 - Speaker Deck

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Unit Testing 101 Wednesday, October 12, 11

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Jim Holmes @aJimHolmes [email protected] http:/ /blogs.telerik.com/ JimHolmes Wednesday, October 12, 11

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Types of Automated Testing Wednesday, October 12, 11

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Functional: Complete slice of functionality, generally at UI V E R Y S L O W Wednesday, October 12, 11

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Integration: Testing across components or layers (web services, eg) Generally slow (ish) Wednesday, October 12, 11

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Unit Testing: Small isolated portions of code. No dependencies -- VERY fast Wednesday, October 12, 11

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Testing Methodologies Wednesday, October 12, 11

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Test Occasionally Write tests (maybe) for easy stuff, or to cover a bug. Occasionally, like. Wednesday, October 12, 11

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Test After Dev Write your system, then write some tests. Emphasis on “some” because it tends to get blown off... Wednesday, October 12, 11

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Test Driven Development Write tests first, then write code to make tests pass Wednesday, October 12, 11

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Behavior Driven Development Like TDD, but sounds cooler Wednesday, October 12, 11

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OK, BDD seriously “TDD helps you write software correctly, BDD helps you write the correct software.” --Aslak Hellesoy Focuses on how system should behave -- interactions & outcomes, not just inputs/outputs Wednesday, October 12, 11

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Why Test? Wednesday, October 12, 11

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Prove you’ve fixed the bug Wednesday, October 12, 11

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Tripwire against regressions Wednesday, October 12, 11

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Prove your acceptance criteria are met Wednesday, October 12, 11

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Lower risk Wednesday, October 12, 11

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Automate testing so you can focus your brain on VALUE Wednesday, October 12, 11

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It takes time.... Wednesday, October 12, 11

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Cons of Testing Wednesday, October 12, 11

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Design impacts Wednesday, October 12, 11

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Brittle, bad tests are a time sink (and morale, too) Wednesday, October 12, 11

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New skills needed ooooh, that’s scary Wednesday, October 12, 11

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Pros of Testing Wednesday, October 12, 11

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Safety net Wednesday, October 12, 11

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Tests == Documentation (sort of) Wednesday, October 12, 11

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Quality (Duh) Wednesday, October 12, 11

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Flexibility & Speed I can change with confidence (or at least less fear) Wednesday, October 12, 11

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What’s a Good Unit Test? Wednesday, October 12, 11

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Granular Check one thing, and one thing only! (Mostly) Wednesday, October 12, 11

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No Dependencies Dependencies external to the test get mocked Wednesday, October 12, 11

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Readable Tests are system knowledge. Make sure they’re understandable! Wednesday, October 12, 11

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FAST! Slow unit tests indicate mixed concerns, too much responsibility, dependencies Wednesday, October 12, 11

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CORRECT! Bad tests kill kittens Wednesday, October 12, 11

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ENOUGH TALK! LET’S CODE! Wednesday, October 12, 11

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The Tools Test Frameworks MbUnit (Gallieo) www.Gallieo.org Nunit www.NUnit.org Mocking Frameworks Rhino Mocks http://is.gd/bCCk9 Moq http://is.gd/bCCim NMock http://nmock.org Telerik’s JustMock http://is.gd/bCCbq Wednesday, October 12, 11

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Books Roy Osherove's Art of Unit Testing Bob Martin's Agile Patterns & Principles in C# Hunt & Thomas's Pragmatic Unit Testing (C#/.NET) Wednesday, October 12, 11

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Jim Holmes @aJimHolmes [email protected] http:/ /blogs.telerik.com/ JimHolmes Wednesday, October 12, 11