Visual Studio 2010 Unit Testing

164 Pages·2013·1.75 MB·English

Testing In
Visual Studio 2010
Benjamin Day
Copyright © 2013, Benjamin Day Consulting, Inc. www.benday.com 1
Benjamin Day
• Consultant, Coach, Trainer
• Scrum.org Classes
– Professional Scrum Developer (PSD)
– Professional Scrum Foundations (PSF)
• TechEd, VSLive, DevTeach, O’Reilly OSCON
• Visual Studio Magazine, Redmond Developer News
• Microsoft MVP for Visual Studio ALM
• Team Foundation Server, TDD, Testing Best Practices,
Silverlight, Windows Azure
• http://blog.benday.com
•
Agenda
• What is Test Driven Development?
• How do you do Test Driven Development in VS?
• Why Test Driven Development?
• How much is enough?
• Code Coverage
• Code Profiling
• Data-driven Tests
• Ordered tests
• Dynamic Mocks using RhinoMocks
• Design for Testability
• User Interface Testing
Copyright © 2013, Benjamin Day Consulting, Inc. www.benday.com 3
What is Test Driven Development?
• Way of developing code so that you always
have proof that something is working
– Code that validates other code
– Small chunks of “is it working?”
• Small chunks = Unit Tests
• Kent Beck (“Test-Driven Development”,
Addison-Wesley) says “Never write a single
line of code unless you have a failing
automated test.”
Copyright © 2013, Benjamin Day Consulting, Inc. www.benday.com 4
What is a Unit Test?
• Wikipedia says, “a unit test is a procedure
used to validate that a particular module of
source code is working properly”
• Method that exercises another piece of code
and checks results and object state using
assertions
Copyright © 2013, Benjamin Day Consulting, Inc. www.benday.com 5
How to begin?
• Get an idea for what you want to develop
• Brainstorm success and failure scenarios
– These become your tests
Copyright © 2013, Benjamin Day Consulting, Inc. www.benday.com 6
The Process
• From William Wake’s “Extreme Programming
Explored” (Addison-Wesley)
1. Write the test code
2. Compile the test code  Fails because there’s no
implementation
3. Implement just enough to compile
4. Run the test  Fails
5. Implement enough code to make the test pass
6. Run the test  Pass
7. Refactor for clarity and to eliminate duplication
8. Repeat
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Structure of a Unit Test
• Arrange
– Set up the System Under Test (SUT)
• Act
– Run the operation(s)
• Assert
– Verify that it worked
Copyright © 2013, Benjamin Day Consulting, Inc. www.benday.com 8
SO, HOW DO I DO TDD IN
VISUAL STUDIO 2010?
Copyright © 2013, Benjamin Day Consulting, Inc. www.benday.com 9
Basic structure of a Visual Studio unit
test
• Microsoft.VisualStudio.QualityTools.UnitTestFramework
• Test fixture (aka Test Class)
– Marked with the [TestClass] attribute
– Collection of unit test methods
– Needs a parameter-less constructor
• Unit test method
– Marked with the [TestMethod] attribute
– Must be public
– Must return void
– No method parameters
Copyright © 2013, Benjamin Day Consulting, Inc. www.benday.com 10