Roy Osherove teaches how to use Typemock Isolator to write unit tests for legacy code that cannot be changed. 23-11-2010

1. 1
Roy Osherove
CTO, Typemock
Unit Testing
Legacy Code
With
Isolator
@RoyOsherove

2. 2
Twitter : Ask @Typemock
under #Legacy
Asking Questions

3. 3
Answer Survey
Giveaways:
2 Isolator Licenses

4. Our Application
BlogEngine.NET
 Download the code
 Follow Along
http://blogengine.codeplex.com/

5. What shall we test?
Blog Post Manager PingTrackback.Send(..)
PingTrackback
Servers

6. Legacy Code Ahead
 Lots of Dependencies
 Unknown Beforehand
 Many Rules Don’t Apply
 Tests are longer, and
harder to read
 Better to start with
integration tests
7

7. Demo
Excavating Code with Isolator
 Wishful Invocation
 Get dependency exception
 Choose Dependency from stack
 FAKE dependency

8. Summary
 Approach Legacy With Caution
 Choose the right level of isolation
 Use Broad Strokes when Faking Legacy
 Maintainability
 Readability
 See tests fail and pass
 trust
9

9. More Advice
 Typemock Forums
 http://forums.typemock.com/
 Support staff
 Blog.typemock.com
10

10. VS Versions
• Supports vs
2005-2010
• Supports .NET
2.0 – 4.0
Fakes
• Any Legacy
Code
• IntelliTest
Suggestions
3rd party
• Works with
other profilers
• Extensible
IntelliTest
• Extensible
CThru

11. 12
Easy, Correct & Effective Unit Testing
“Typemock - My testing tool of choice. Each time I use it, I
rediscover its power, and I'm amazed. Great tool!”
Jason C Divis, @CodingOfficer

12. 13
Twitter : Ask @Typemock
Asking Questions

13. 14
Answer All Survey Questions
after this webinar finished
Giveaways:
2 Isolator Licenses

14. Thanks
15
Roy Osherove
CTO, Typemock
royo@typemock.com