Chapter 4
Classic TDD III – Transformation Priority Premise
As tests get more specific, code gets more generic.
– Robert C. Martin
When a friend mentioned the Transformation Priority Premise (TPP) in a mob session we were doing in the Arctic region of Finland, I was baffled. I had been practicing Test-Driven Development (TDD) for many years and considered myself an above-average practitioner, yet I had never heard of TPP. As soon as I had a moment with my friend, I grilled him with questions and then spent the night in my cabin learning it.
TPP is quite important in the context of TDD as it defines obvious implementation. Before finding out about TPP, I had been using instinct/intuition, experience, and feedback. TPP brings a bit of process and rationale to evolving code.