Running pytest.main() as a coroutine

[rmartin16]

Curious about high-level thoughts/approaches to a situation.

We're using pytest to run a test suite against an application that leverages an event loop that's sometimes provided by the platform; this loop is hooked in to asyncio to allow a similar API for interacting with them across platforms.

For testing, we are shunting pytest.main() in to a thread; this thread is started as part of the application's start up process once the event loop is started in the main thread. From there, the tests can run using the application's event loop with some magic from pytest-asyncio.

This creates at least two problems for us:

• Having multiple threads in Python can create conflicts in the third-party native code we're dealing with....but these have been proven mostly manageable
• Some platforms, such as wasm, don't support threads....so we can't run this testing strategy there

I did find alt-pytest-asyncio....but it appears to try running pytest.main() in a loop nested within the already running loop. asyncio as well as the other event loops we're using don't support nested loops.

So, we're thinking...what if we could add pytest.main() as a coroutine to the event loop? Superficially, at least, this seems far from trivial right now....given pytest doesn't seem to support anything like that.

But I was curious if anyone's come across this or thought about a similar situation before. Thanks.

[RonnyPfannschmidt]

This would quite likely require coloring much of the internals

As such its currently not feasible to consider as a endgame

It's however a topic that may be interesting for the sprint to consider

But until pluggy is more async aware it's unlikely

There's some experiment's for integration of asyncio and greenlets

Currently I suspect that greenlets are the most workable tools to drive this, this is to be taken with salt