Creating High Quality Visual Studio extensions

1. Writing High Quality Visual Studio Extensions Omer Raviv | omerr@codevalue.net | @omerraviv www.oz-code.com | @oz_code Testable, stable, performant, memory efficient

2. 2 @omerraviv on Twitter (twitter picture) @omerraviv on Gitter.im/extendvs (Gitter logo) Omer Raviv • Creator and CTO of OzCode • Senior Consultant @ CodeValue • .NET open-source enthusiast • Passionate about dev productivity @omerraviv on Twitter @omerraviv on Gitter (gitter.im/extendvs)

3. My Journey as a developer

4. Every minute spent in the debugger is a minute squandered

5. The two most common ways to use a debugger: 1. Wasting time 2. Quality time

6. Wasting time: Not knowing what your hypothesis is at any given time Getting into a rot mindlessly hitting F10 Quality time: Apply the Scientific Method, religiously Simplify the scenario, then write a test! The Debugging Process Overview !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

7. Why can’t Johnny do Test Driven Development?

8. A typical unit test Test Driven Woes

9. 2 Unit Tests. 0 Integration Tests.

10. UI System/ Subcutaneous Unit Automation Harder Easier Exploration Mike Cohn’s Test Automation Pyramid Writing test at the right level of granularity

11. UI System/ Subcutaneous Unit Exploration Writing test at the right level of granularity Microsoft/VisualStudio-TestHost/TestUtilities , PTVS JaredPar/VsVim/Test OzCode/VSIntegrationTestSamples

12. • Synthesis and refinement of practices stemming from TDD & ATDD • User story: "As a [role] I want [feature] so that [benefit]” • Acceptance Criteria Given [initial context] When [event occurs] Then [ensure some outcome] What’s this BDD thing?

13. Create living, executable Specification. New feature? Can I see the requirements doc please? What’s BDD all about?

14. • Use natural language to express intentions (Given…When…Then) • Use a general purpose programming language to express test mechanics • Use a tool that will let you operate in either domain seamlessly BDD offers a solution

15. Michael WhelanMehdi Khalili Jake Ginnivan Jason Roberts PM> Install-Package TestStack.BDDfy

16. • Works with any testing framework • Does not require its own test runner • Creates Humanized, story-like error messages A few quick BDDfy facts:

17. Demo time!

18. My very first Visual Studio Subcutaneous Test

19. Having flakey tests is a lot worse than having no tests at all. A flakey test is like a virus – quarantine it, then triage. Visual Studio Integration Tests Pro-Tip

20. Writing High Quality Visual Studio extensions Omer Raviv | omerr@codevalue.net | @omerraviv www.oz-code.com | @oz_code Testable, stable, performant, memory efficient

21. The ActivityLog.xml MessageBox …of pain and suffering

22. The ActivityLog.xml MessageBox …of pain and suffering github.com/oz-code/OzCode.VisualStudioExtensionAnalyzers PM> Install-Package OzCode.VisualStudioExtensionAnalyzers

23. Use an Exception Monitoring Tool Use an Exception Monitoring Tool

24. Use an Exception Monitoring Tool

25. Dealing with crashes Starting with VS2017.3, users get a notification if an exception might be involved in a crash.

26. https://gist.github.com/oz-code/76446034c493685bfaabdd5aecc43180 Dealing with crashes

28. Visual Studio 2017 will warn users about extensions that are slowing things down. Performance as a Feature

29. 1. Delay loading your extension as much as possible (using UIContextRule) 2. When you do load, load in the background. (using AsyncPackage) Performance as a Feature

30. OzCode F10 Monkey http://www.github.com/oz-code/VSExplorationTests

32. Memory Leaks vs. GC Pressure GC Pressure: Memory Leak:

33. Memory Leaks vs. GC Pressure Pro-Tip: Don’t Close your Diagnostics Tools Window!

34. Dealing with GC Pressure Memory Leaks vs. GC Pressure • Always be measuring (allocations, % time spent in GC) • Watch out for duplicate strings • Use object pooling / a string intern pool • Use Roslyn Heap Allocation Analyzer

35. github.com/jaredpar/vsvim Memory Leak Testing Subcutaneous Tests Pro-Tip

36. Memory Leak Testing Subcutaneous Tests Pro-Tip

37. Which means… …a business sponsor could request that the current development version of the software can be deployed into production at a moment's notice - and nobody would bat an eyelid, let alone panic. Got good Subcutaneous Tests? Start practicing True Continuous Delivery! Martin Fowler

38. Thank You! @oz_code http://oz-code.com