My talk on i4cup meetup

My talk on small local i4cup meetup. Telling about my Swift fuckup :)

Transcript

1. i4☕
2. Code that smells aka ‘bydlo-code’
3. kill me, please
4. don’t write code that smells
6. there was a dev team…
7. there was a dev team… …writing on ObjC
8. and they decided to switch to Swift!
9. and they decided to switch to Swift! in production!
11. it was nice morning and PM decided to install app
12. it was nice morning and PM decided to install app on device!
14. it’s not us! it’s new 7.3 Xcode!
15. oh no, it’s us :(
16. "loadData has not been implemented" found in logs
18. – loadData(…) -> … – loadData(…) -> … ChildTableViewController <T> BaseTableViewController <T>
19. BaseTableViewController <T> – loadData(…) -> … ChildTableViewController <T> – loadData(…) -> … generics stub overriden
20. BaseTableViewController <T> – loadData(…) -> … ChildTableViewController <T> – loadData(…) -> … generics stub overriden not called at all
21. A – architecture
22. Problem solving
23. What if we disable optimization?
24. let’s disable optimization..
25. too many optimizations! swift compiler optimization!
26. Why debug is ok?
27. …Testability
28. Debug Release Optimization Testability WMO yes WMO no
29. WMO https://developer.apple.com/swift/blog/?id=27 if method has no ‘internal’ access, compiler may mark it as ‘final’
30. Testability allows you to use all ‘internal’ methods in tests like ‘public’
31. everything is ok overriden methods may be lost Debug Release Optimization Testability WMO yes WMO no
32. tweet all the things!
33. tweet all the things!
34. sudden help!
35. sudden help! swift contributor
36. https://gist.github.com/PaulTaykalo/5c97010874a93626ca3c Minimal crashable code
37. http://openradar.appspot.com/radar?id=4971716266688512 Filed Radar
38. SIL devirtualization: Conservatively avoid filtering devirt candidates on generic base classes Fix by @jckarter https://github.com/apple/swift/pull/1954
39. SIL devirtualization: Conservatively avoid filtering devirt candidates on generic base classes Fix by @jckarter https://github.com/apple/swift/pull/1954
40. Fix by @jckarter fix! https://github.com/apple/swift/pull/1954
41. Tests https://github.com/apple/swift/pull/1954
42. Swift 2.2 Patch https://github.com/apple/swift/pull/1954
43. Lessons learnt
44. Lesson #1 every decision has consequences
45. sooner or later they’ll appear Lesson #1 every decision has consequences
46. Lesson #2 always try build in release on device
47. at least once a day Lesson #2 always try build in release on device
48. and community Lesson #3 twitter rulez
49. Lesson #4 PMs are useful
50. sometimes Lesson #4 PMs are useful
51. team: Vitaliy, Igor, Paul Thanks community: @akosma, @jckarter PM: Anna