Is there an idiomatic way to override the default dispatcher for unit tests? or would this be considered bad practice, and typical injection preferred?

What is your use case for this? You can specify amount of threads for default dispathcer, but there is no way to completely replace it (except reflections), usually it shouldn’t be a problem for unit tests if you just use suspend functions and test them or just have access to Job

It’s only when unit testing classes that construct a coroutine consuming suspended functions, it needs to provided with a dispatcher or scope via constructor injection which can be changed under test.

I treat it as any other static dependency and pass it in.

For UI dispatcher you always should provide it

Yep, I figured as much, I just thought I’d ask 👍