1. Refactoring your way
out of the mess
@WolframKriesing, uxebu - JavaScript company

2. Improve structure all the time
was not possible with this tower, of course

6. A bit of history

8. Design is hard.
The design of
reusable software
is especially hard.
Reusable software usually is the
result of many design iterations.
William F. Opdyke, 1992
it’sallaboutdesign

11. http://martinfowler.com/books/refactoring.html

12. base
controlled technique
code
improving design

13. applying
series small
tranformations too small to be worth doing

14. tranformations
cumulative
significant

15. error
small steps
reduce risk

16. avoid
system
broken
carrying out
restructuring

17. allows
gradually refactor
system
extended period of time

19. Reasons to refactor
(refactoring workflows)

20. http://martinfowler.com/articles/workflowsOfRefactoring/

22. # 1

24. #2 - Litter-Pickup

25. #3comprehensionrefactoring

26. prepare
#4

27. #5

29. #6 Long-Term
Refactoring
• Design
• Gradually get to a new design
• Little jumps
• Parallel refactoring

30. „If somebody talks about a system being
broken for a couple of days while they
are refactoring, you can be pretty sure
they are not refactoring.“
http://martinfowler.com/bliki/RefactoringMalapropism.html

31. 1 TDD Refactoring
2 Litter-Pickup Refactoring
3 Comprehension Refactoring
4 Preparatory Refactoring
5 Planned Refactoring
6 Long-Term Refactoring

32. –Martin Fowler
„Refactoring (noun):
a change made to the
internal structure of
software to make it easier to
understand and cheaper to
modify without changing its
observable behavior.“
Why?
How?
What?

33. Write Code
Read Code

34. Easier to understand?
- less to read!
- expressive

35. The Power Of (Long) Names

36. Let’s use our time more efficiently!

37. How?
How?

38. „If you are doing refactoring
your system should
not be broken for more than
a few minutes at a time“
http://martinfowler.com/bliki/RefactoringMalapropism.html

39. broken?
requires tests

40. –Martin Fowler
„Refactoring (noun):
a change made to the
internal structure of
software to make it easier to
understand and cheaper to
modify without changing its
observable behavior.“
stay green

43. stay green
reflected in tests

44. Tests?
LEGACY

45. Tests?

47. http://www.merriam-webster.com/dictionary/observable
observable
behavior
implementation detail
test this
DONT test this

48. implementation detail

49. test right!
OR disable refactoring

50. Tests?

51. „If you are doing refactoring
your system should
not be broken for more than
a few minutes at a time“
http://martinfowler.com/bliki/RefactoringMalapropism.html

53. baby stepping on green

54. baby steps
stay green
have the right tests
don’t test
implementation detail

55. Why refactor?

56. think in economics
not in code ethics

57. http://martinfowler.com/bliki/DesignStaminaHypothesis.html

58. What to refactor

59. https://github.com/
emilybache/
Tennis-Refactoring-Kata

64. thx
@WolframKriesing, uxebu - JavaScript company