I can’t test this code because the design is awful. I can’t refactor because I don’t have tests. Yet it keeps having (and breeding) bugs. Now what? — Everyone, everywhere
Arlo has talked in the past about how this apparent catch-22 is resolved by a better understanding of the word “refactoring” — that using a specific set of techniques allows defect detection and prevention even in untested — or untestable — code.
In this session he shows you those techniques by applying them to some gnarly code.
This session is 75% live-coding, 25% talking.
Most of the talking is Arlo asking questions. So watch this session if you want to think, want to get your hands dirty, and want to see specifics that you can try to apply immediately in your own code.
Agenda:
- Microtesting: understanding what the code does and deriving a spec.
- Resolve microtesting blocker: mechanically spot CQRS violations; resolve them via extract method + make method static.
- Resolve microtesting blocker: mechanically spot multiple responsibilities in a class; resolve them via extract method + make method static + introduce parameter object.
- Safeguarding: preventing bugs by eliminating hazards.
- Remove hazard: primitive obsession leads to inconsistent computation; resolve it via introduce parameter object + extract method + move method.
