in netbench/src/multiplex.rs [327:337]
fn poll_accept_stream(&mut self, _cx: &mut Context) -> Poll<Result<Option<u64>>> {
if !self.rx_open {
return Ok(None).into();
}
if let Some(id) = self.pending_accept.pop_front() {
Ok(Some(id)).into()
} else {
Poll::Pending
}
}