terminate worker thread as soon as possible to avoid race conditions

src/spotify.rs

@@ -143,6 +143,12 @@ impl futures::Future for Worker {
         loop {
             let mut progress = false;
 
+            if self.session.is_invalid() {
+                self.player.stop();
+                self.events.send(Event::Player(PlayerEvent::Stopped));
+                return Poll::Ready(Result::Err(()));
+            }
+
             if let Poll::Ready(Some(cmd)) = self.commands.as_mut().poll_next(cx) {
                 progress = true;
                 debug!("message received!");
@@ -216,11 +222,6 @@ impl futures::Future for Worker {
                 _ => (),
             }
 
-            if self.session.is_invalid() {
-                self.events.send(Event::Player(PlayerEvent::Stopped));
-                return Poll::Ready(Result::Err(()));
-            }
-
             if !progress {
                 return Poll::Pending;
             }