Sample code for testability series on
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This code repo is in place to support my testability series of posts. I started with a Plea for Testability and then that transitioned into an Ode to Testability, which will span a number of posts.

This is a contrived example of an application that is designed entirely for pedagogical purposes. There is a lot going on in those posts. Specifically, I had a series of goals. Some of those are as follows:

  • Show how TDD can go really well but also how, sometimes, you can lead yourself astray with it.

  • Show why the "testing vs checking" distinction is probably useless, definitely counterproductive.

  • Show how the intersection of TDD and BDD can be complicated, or not, depending on the tightness of the feedback loop.

  • Show what design pressure means in the context of value and correctness.

  • Show how value and correctness operate with a goal of testability in mind.

  • Show how testability needs to be treated as a primary quality attribute.

  • Show the intersection of testing as a design activity and testing as an execution activity.