asyncio.future.wrap_future is used to wrap a concurrent.future.Future in a asyncio.future.Future. 

The actual implementation as the following behaviours : 

 1) When the concurrent.future.Future gets a result, the asyncio.future.Future gets the same result,
 2) When the asyncio.future.Future is cancelled, the concurrent.future.Future is cancelled

I wonder why the futures synchronisation is not symmetrical ?
I propose to add the following behaviours : 

 3) When the asyncio.future.Future gets a result, the concurrent.future.Future gets the same result,
 4) When the concurrent.future.Future is cancelled, the asyncio.future.Future is cancelled

I have also posted a request pull that implements the proposed behaviours, in case of acceptation.

If there is good reasons to not implement the proposed behaviours, I would be glad to know.

Thank you !

Actually the PR does not pass some tests, I will work on this. If the new behaviours are accepted, I will implement them soon.

The proposed solution (PR) has passed all tests.

The PR needs a very careful review, but in general I'm OK with the idea.  I'm also curious why do you want to fix wrap_future -- how are you using it?

I use it to integrate a concurrent-based software (B) with an asyncio-based software (A).
(B) will undergo a massive refactoring to become asyncio-based in the future, but for now, I need to use it as-is.
I don't want to modify (A) to handle concurrent.futures.Future (it is developped by another team by the way) and I prefer to begin to implement asyncio into (B).

So (A) waits for a task request with an asyncio.Future, then processes it and populates the Future's result.
(B) has a waiting loop into a thread that handles multiples concurrent.futures.Future.

When (B) receives a request it creates a concurrent.futures.Future and push it into a queue for the waiting loop. If the request asks for a task implemented by (A), it wraps it into an asyncio.Future and call (A) with it.
(A) processes the task and populates the asyncio.Future's result. That's why I needed to implement the proposed behaviours.

Actually I will not need it for long, as (B) will become asyncio-based, but I wanted to integrate (A) and (B) with as less effort as possible, so I implemented my custom Future wrapper, but I think it is useful to refactor concurrent-based software to asyncio incrementally (and I will have to do it multiple times in the near future).

Can be closed if not needed by the community.

stage: patch review -> resolved