TDD on Three Index Cards 7
I had the opportunity to talk to a fellow who missed part of a class on TDD. I told him that I could give him a 15-minute overview, and give him all the essentials of TDD on three index cards.
Yes, I know that volumes have been written about TDD and BDD, and that it’s a large topic with many many branches of application, but I didn’t have time for that. I had time for three index cards. I figure that an index card is a token, and it represents a conversation, and that one can always dig deeper later.
They looked more or less like this:
Card 1: Uncle Bob’s Three Laws (Object Mentor)
- Write no production code except to pass a failing test.
- Write only enough of a test to demonstrate a failure.
- Write only enough production code to pass the test.
Card 2: FIRST Principles (Brett and Tim at Object Mentor)
- Fast: Mind-numbingly fast, as in hundreds or thousands per second.
- Isolated: The test isolates a fault clearly.
- Repeatable: I can run it repeatedly and it will pass or fail the same way each time.
- Self-verifying: The test is unambiguously pass-fail.
- Timely: Produced in lockstep with tiny code changes.
Card 3: Flow (using the famous three-node circle diagram) – origin unknown.
- Red: test fails
- Green: test passes
- Refactor: clean code and tests
Sure there is plenty more, but I didn’t know how I could provide significantly less. As is, I’m pretty happy with the exercise. Now I am wondering if I couldn’t produce most of the important information I wish to convey as a series of index cards. Would that be cool or what?