Path From Legacy Code To Unit Tests
Llewellyn Falco http://llewellynfalco.blogspot.co.uk
1. organise team to do 2 hours of mob programming a day (see mobprogramming.org and https://en.m.wikipedia.org/wiki/Spaced_repetition)
2. get into habit of extracting methods and renaming - that's all the mob does to start
- 7 stages of naming - Belshee https://mobile.twitter.com/arlobelshee/status/636605852984545280/photo/1
* nonsense * honest * honest & complete * does the right thing * intent * domain abstraction
(Note TDD starts at end - domain abstraction - and works backward!)
3. repeat until you find a functional component (input->deterministic processing->output)
4. create unit test using poking. Determine what the functional component does by passing in simple, valid, self-documenting values like 0, 1, "FirstName", "FlightNumber", or even null. Whatever it returns (if not an exception) is right - put it into a test and check it in
5. start measuring code coverage
6. so far we have been extracting functional components by accident - now we can start making simple changes, like extracting parameters previously read from a web request, that make components functional
7. larger modifications
8. mocking
9. modifictation to lighten the mocks
10. now we can actually do a little bit of test-first!
this takes a couple of months at 2 hours/day