Programming

The author’s primary gripe, IMHO, has legs: the question about the oven’s relationship to baking is buried as part of bake() and is weird. But the solution here is not the left-hand code, but rather to port some good, old-fashioned OOP patterns: dependency injection. Pass a reference to an Oven in createPizza() and the problem is solved.

Doing so also addresses the other concern about whether an Oven should be a singleton (yes, that’s good for a reality-oriented contrived code sample) or manufactured new for each pizza (yes, that’s good for a cloud runtime where each shard/node/core will need to factory its own Oven). The logic for cloud-oven (maybe like ghost kitchens?) or singleton-oven is settled outside of the narrative frame of createPizza(). Again, the joy of dependency injection.

To their other point, shouldn’t the internals of preheating be enclosed in the oven’s logic…why yes that’s probably the case as well. And so, for a second time, this code seems to recommend OOP. In Sandi Metz style OOP in Ruby (or pretty much any other OOP language) this would be beautiful and rational. Heck, if the question of to preheat or no is sufficiently complex, then that logic can itself be made a class.

As I write, I thought: “How is golang so bad at abstraction?” I’m not sure that that is the case, but as a writer of engineering education, I think the examples chosen by the Google Testing Blog don’t serve well. Real-world examples work really well with OOP languages, fast execution and “systems thinking” examples work great with golang or C. Perhaps the real problem here is that the contrived example caters to showing off the strengths of OOP, but uses a procedural/imperative-style-loving language. Perhaps the Testing Blog folks assumed that everyone was on-board with the “small factored methods approach is best” as an article of faith and could accept the modeled domain as a hand wave to whatever idea it was they were presenting.