Legacy Code Kata at SWK Berlin

Our slides with rradczewski from the Legacy Code Kata, October '15.

Transcript

1. Legacy Code Kata 26 Oct @ innoQ
2. Not only working software, but also well-crafted software
3. Taking the time to refactor after making it “work” Avoiding Accidental Complexity
4. I fear legacy code
5. You do too (i bet…)!
6. No Tests No (up-to-date) Specification And the author left looooong time ago...
7. But fear not, for you are here tonight :) Last Time Gilded Rose Kata - Test Coverage for adding features Full Evening This Time Trivia Kata - Improving code without adding features Retreat Style
8. Tomorrow, when you get to the office... Gather data Where are your pain points? How often do they hinder you? How much time do you waste because of them? Make it transparent Put up Post-It’s with your “best” pain points Let other developers vote on them or add others Build prototypes Prove that you can improve your codebase for simple use-case
9. Big Thanks to innoQ for having us this evening
10. We’re looking for Sponsors & Venues ! Connect us to your employer, will ya :)
11. ONLY 4 SEATS LEFT Global Day Of CodeRetreat 14. Nov 2015 @ Wooga
12. git.io/ vWrFn https://github. com/jbrains/trivia
14. Safety Net Toolbox - Test coverage - Golden master technique - Use your IDE refactoring tools - Commit often to your local version control - Mutation testing (do the tests fail if we introduce mutants in the code)
15. Test Coverage - No specifications but GameRunner might help - Use your code coverage tool to improve your safety net
16. Golden Master Technique - Make the system testable - Replace any random number generators/current datetime calls, inject mocks for external stuff - Produce output - Find a balance between pseudo random and specific input or scenarios - Capture the output of the system without changing the production code - In the trivia game, we see lots of console output lines - In your tests, compare the output of the “original” Golden Master to your implementation
17. Use Your IDE Improve readability ~ Find code duplicates and extract methods ~ Isolate calls to low level classes, things which write to or read from sources ~ Fix stringly typed variables
18. FIND YOUR PAIR