Add test that a window update can be received in reserved state (#195)

src/proto/streams/prioritize.rs

@@ -238,6 +238,11 @@ impl Prioritize {
             stream.send_flow
         );
 
+        if stream.state.is_send_closed() && stream.buffered_send_data == 0 {
+            // We can't send any data, so don't bother doing anything else.
+            return Ok(());
+        }
+
         // Update the stream level flow control.
         stream.send_flow.inc_window(inc)?;
 

src/proto/streams/recv.rs

@@ -745,6 +745,10 @@ impl Recv {
             if !stream.state.is_recv_streaming() {
                 // No need to send window updates on the stream if the stream is
                 // no longer receiving data.
+                //
+                // TODO: is this correct? We could possibly send a window
+                // update on a ReservedRemote stream if we already know
+                // we want to stream the data faster...
                 continue;
             }
 

src/proto/streams/state.rs

@@ -361,6 +361,13 @@ impl State {
         }
     }
 
+    pub fn is_send_closed(&self) -> bool {
+        match self.inner {
+            Closed(..) | HalfClosedLocal(..) | ReservedRemote => true,
+            _ => false,
+        }
+    }
+
     pub fn is_idle(&self) -> bool {
         match self.inner {
             Idle => true,