Added additional logging to find try script issues with provider_loop example

Author: tkmcmaster

lib/channel/src/lib.rs

@@ -592,13 +592,19 @@ impl<T: Serialize> Stream for Receiver<T> {
     fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<Option<Self::Item>> {
         debug!(
             "Receiver:poll_next channel {}, length: {}",
-            self.channel.name, self.channel.name
+            self.channel.name, self.channel.len()
         );
         loop {
             if let Some(listener) = self.listener.as_mut() {
                 match Pin::new(listener).poll(cx) {
-                    Poll::Ready(()) => self.listener = None,
-                    Poll::Pending => return Poll::Pending,
+                    Poll::Ready(()) => {
+                        debug!("Receiver:poll_next channel {}, listener Poll::Ready, listener = None", self.channel.name);
+                        self.listener = None;
+                    },
+                    Poll::Pending => {
+                        debug!("Receiver:poll_next channel {}, listener Poll::Pending", self.channel.name);
+                        return Poll::Pending;
+                    },
                 }
             }