Understanding Problems in Smaller Chunks

Incrementally define your problem specification using tests.

4-part unit testing gave many advantages but still isn’t enough. It reduced the cost of writing tests, but you still write those tests either before or after writing the product code. This means that you have to write a large amount of problem, then enough solution to pass it, and back and forth. This module introduces stick-figure testing, which allows you to develop both problem and solution together, in small bits as you go.

Completing this module allows:

  • Rapid iteration on problem and solution before any design starts.
  • Develop design based on working code.
  • Extend existing code incrementally, even if the existing design doesn’t allow for that.


1 — Accomplish Your Goal in Small, Testable Steps

What are the common threads you’ve learned so far and how will you take them forward?

2 — Introduce and Test New Functionality

Identify the problem before assuming solutions.

3 — Move Functionality to Product

Create design now that code is written.

4 — Merge and Re-use Product Code across Tests

Use stick-figure testing to modify existing code.