Check select! bug in async

[joshka]

I suspect that this is still a bug as the select can complete on either branch of the select in a non-deterministic fashion. The right way to handle (I think) is to not fail when the sender fails to send. The send failing can indicator that the receiver is closed. See https://docs.rs/tokio/latest/tokio/sync/mpsc/struct.Sender.html

I think there's probably a second bug with this in how cancelations are handled https://docs.rs/tokio/latest/tokio/sync/mpsc/struct.Sender.html#cancel-safety

Originally posted by @joshka in #48 (review)

[MMitsuha]

Sorry for late response, I am in school now.
Maybe we need a simplified test to validate this

[orhun]

Is this still an issue?

[joshka]

This is mostly a prompt to check whether this is a bug at some point. I haven't looked into it more than superficially.