Execute tasks on SerialExecutionContext outside of a test

[LeifW]

When using AsyncTestSuite (which provided an implicit ExectionContext with SerialExecutionContext), it may sometimes be necessary to run cleanup code after all the tests have executed - e.g. in afterAll. However, if that cleanup code involves dispatching to the ExecutionContext, those won't get run (and thus any Awaits will time out).

SerialExecutionContext is private, so I can't invoke the runNow method directly on there. The way I've hacked around this for now is by reflectively calling runNow after the Futures have been dispatched in afterAll:

val runNow = PrivateMethod[Unit](Symbol("runNow"))
executionContext invokePrivate runNow(Future.successful(Succeeded))

Perhaps exposing something like that to be more conveniently called in afterAll would be nice? (Just making SerialExecutionContext not private would be an improvement).

I get that this is intended for use during tests, but ExecutionContexts aren't always passed granularly enough for me to use one during test code and another during cleanup / shutdown code.

It seems ExecutionContext.parasitic also accomplishes the goal of keeping things single-threaded, and it doesn't require me to "run" the tasks submitted to it. Is there any advantage to using SerialExecutionContext over ExecutionContext.parasitic?

[cheeseng]

@LeifW SerialExecutionContext is just a simple form of default execution context, which was there before ExecutionContext.parasitic was introduced, and we still need to support older Scala version 2.10/2.11. I think you may try to override executionContext with ExecutionContext.parasitic or your custom SerialExecutionContext by just copying the original code and modify.