Refactor asyncio.wait_for()

[asvetlov]

No description provided.

[graingert]

@asvetlov I've been having a go at this branch in bf594bd

you need to special case None in asyncio.wait_for(

Suggested change

	async def inner():
	if timeout is None:
	return await fut
	async def inner():

and then special case 0 in timeouts.timeout see https://gist.github.com/graingert/ea2546b23b32be5a4493a9a115db2eff#file-timeout_bug-py-L6

[graingert]

I don't think this extra create_task is worth it, the tests it passes are equivalent to:

async def wait_for(fut, delay):
    if delay is None:
        return await fut
    if delay <= 0:
        if asyncio.iscoroutine(fut):
            fut.close()
            raise TimeoutError

[graingert]

I think it would be better to skip this create_task and delete the tests that fail