Use Ruff for linting

[unkcpz]

The ruff pre-commit configs are mainly get from aiida-core.
For the linter complain in tests, I simply add # noqa to silent those.

• rename test folder to tests

[unkcpz]

The linter complain is the reference to the coroutine is not returned. I think the standard way is to use the task to do graceful shutdown.
I'll further investigate on it, what I think is the returned reference to the task returned to the function where it is called (ProcessLauncher) and before this task get run it can be cancelled without other exception from the event loop.

[unkcpz]

Let me know if you think it is better to not put dev notes in the src code. @agoscinski

[agoscinski]

Should be okay but I dont fully understand this comment What does the XXX mean? Shouldn't ensure_future return a Future or Task? What do you mean with "reference"?

[unkcpz]

According to https://docs.python.org/3/library/asyncio-future.html#asyncio.ensure_future, the API is deprecated and using create_task is in favor. It returns a task, and task is a future like object that can be resolved by running at event loop.

The reference means the task reference as the handler that can pass around to control this created task. At the moment, we did nothing to the task if other issues happened in the event loop. One example in my mind was when the proc.step_until_terminated() is scheduled in the event loop but not yet run, the event loop needs to be shutdown and the handler here need to call to cancel the task in the event loop first.

[agoscinski]

ok and the XXX?

[unkcpz]

I don’t remember where I got this habit from but there are some archaeology post to read about this https://www.snellman.net/blog/archive/2017-04-17-xxx-fixme/

I think for modern ide it is highlighted as TODO nd FIXME.

[unkcpz]

I move the fix for passing 3.12 tests to #292 so this PR only contains the changes recommended from ruff. It is ready to be review.

[sphuber]

Thanks @unkcpz