Why avoid mocks

[josevalim]

@michalmuskala

Having said that, passing the dependency through application environment is indeed a side-effect and may be not considered a good style, but it’s very simple and convenient.

I partially agree. If the value never changes, it will be side-effect free. That’s exactly what happens when the application environment is read at compile-time rather than runtime. The behaviour at runtime is guaranteed to be the same.