Enable _uasyncio module

[t-ikegami]

This PR fixes ticks in moduasyncio.c to work with adafruit version of asyncio, and enables _uasyncio module. With this PR, C-version of Task and TaskQueue are used in the asyncio.

[dhalbert]

The _uasyncio implementation of Task does not provide__await___(). Our internal implementation of async/await (done by @WarriorOfWire) requires that. Otherwise code is going to fail. I had to add __await__() in the Python version in a couple of places:
https://github.com/adafruit/Adafruit_CircuitPython_asyncio/blob/28ef812f14ef1fde1036eb83a4878bd14aa9a67d/asyncio/task.py#L152
https://github.com/adafruit/Adafruit_CircuitPython_asyncio/blob/28ef812f14ef1fde1036eb83a4878bd14aa9a67d/asyncio/core.py#L52-L53

I started to add __await__(), but because __iter__() is provided in a special way, I had not yet figured out how to make it work, and so did not use _uasyncio initially.

In addition, I would like to rename _uasyncio to _asyncio, but that is minor.

[t-ikegami]

Thank you for the comment. Now I understand why _uasyncio is missing in the modules. I'll close this PR.

[dhalbert]

If you can see how to add __await()__, that would be great. but it's rather deep in method resolution. I haven't had time to look further.

[dhalbert]

I appreciate your work, and we can use these commits in the future, in any case.

[t-ikegami]

The __await__ method is added to Task class, which is just a wrapper of getiter. The name of the module is not modified for now, because the renaming should be in sync with adafruit/asyncio/core.py. With this PR, Task object becomes awaitable, and the following code works.

import asyncio

async def coro(s) :
    print("coro start", s)
    await asyncio.sleep(s)
    print("coro done", s)
    return f"coro result({s})"

async def main() :
    print("main start")
    res = await asyncio.gather(coro(1), coro(2), coro(3))
    print(res)
    print("main end")

asyncio.run(main())

[dhalbert]

Thank you for doing this, and testing it! I have a few changes, but I'm glad you were able to figure out an easy way to do this.

[t-ikegami]

The module is renamed from _uasyncio to _asyncio.

The task_getiter and task_iternext are moved back to the original position. A prototype definition of task_getiter is added.

I couldn't figure out MICROPY_PORT_BUILTIN_MODULES stuff well, but the module is now registered not in objmodule.c but by MP_REGISTER_MODULE. (I referred modure.c and modujson.c.)

[t-ikegami]

I appreciate the clarification.

[dhalbert]

I appreciate the clarification.

You were right to use MP_REGISTER_MODULE. The comments re MICROPY_PORT_BUILTIN_MODULES were obsolete. I am having trouble getting it to pass one test. Not quite there yet.

[t-ikegami]

I am having trouble getting it to pass one test. Not quite there yet.

I suspect that tests/unix/extra_coverage.py.exp should be updated (_asyncio module may appear in repl auto-completion), though I failed to build unix/micropython-coverage so far.

[dhalbert]

I suspect that tests/unix/extra_coverage.py.exp should be updated (_asyncio module may appear in repl auto-completion), though I failed to build unix/micropython-coverage so far.

Yes, that was it. I had to sudo apt install pkgconf libffi-dev to get micropython-coverage to build:
make VARIANT=coverage -j12 # or whatever -j is appropriate for you

[t-ikegami]

Thank you for the update.

[dhalbert]

After my last set of tweaks, I tested this with a two-task blinking LEDs program on a Metro M4, and it's working. Thanks for this, @t-ikegami !

[dhalbert]

I have to shrink the matrixportal build slightly, or perhaps turn off uasyncio in that build.