From ddc886be7a30a521369444eb4ff76caf5c6122f5 Mon Sep 17 00:00:00 2001
From: Marten Seemann <martenseemann@gmail.com>
Date: Wed, 29 Jan 2020 11:14:29 +0700
Subject: [PATCH] remove inactive streams from the window update queue

---
 window_update_queue.go      |  2 +-
 window_update_queue_test.go | 26 ++++++++++++++++++++++++--
 2 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/window_update_queue.go b/window_update_queue.go
index 64b912a3f..607b72d7e 100644
--- a/window_update_queue.go
+++ b/window_update_queue.go
@@ -53,6 +53,7 @@ func (q *windowUpdateQueue) QueueAll() {
 	}
 	// queue all stream-level window updates
 	for id := range q.queue {
+		delete(q.queue, id)
 		str, err := q.streamGetter.GetOrOpenReceiveStream(id)
 		if err != nil || str == nil { // the stream can be nil if it was completed before dequeing the window update
 			continue
@@ -65,7 +66,6 @@ func (q *windowUpdateQueue) QueueAll() {
 			StreamID:   id,
 			ByteOffset: offset,
 		})
-		delete(q.queue, id)
 	}
 	q.mutex.Unlock()
 }
diff --git a/window_update_queue_test.go b/window_update_queue_test.go
index 76a6811b0..727565f37 100644
--- a/window_update_queue_test.go
+++ b/window_update_queue_test.go
@@ -52,8 +52,18 @@ var _ = Describe("Window Update Queue", func() {
 	})
 
 	It("doesn't queue a MAX_STREAM_DATA for a closed stream", func() {
-		streamGetter.EXPECT().GetOrOpenReceiveStream(protocol.StreamID(12)).Return(nil, nil)
 		q.AddStream(12)
+		streamGetter.EXPECT().GetOrOpenReceiveStream(protocol.StreamID(12)).Return(nil, nil)
+		q.QueueAll()
+		Expect(queuedFrames).To(BeEmpty())
+	})
+
+	It("removes closed streams from the queue", func() {
+		q.AddStream(12)
+		streamGetter.EXPECT().GetOrOpenReceiveStream(protocol.StreamID(12)).Return(nil, nil)
+		q.QueueAll()
+		Expect(queuedFrames).To(BeEmpty())
+		// don't EXPECT any further calls to GetOrOpenReceiveStream
 		q.QueueAll()
 		Expect(queuedFrames).To(BeEmpty())
 	})
@@ -61,8 +71,20 @@ var _ = Describe("Window Update Queue", func() {
 	It("doesn't queue a MAX_STREAM_DATA if the flow controller returns an offset of 0", func() {
 		stream5 := NewMockStreamI(mockCtrl)
 		stream5.EXPECT().getWindowUpdate().Return(protocol.ByteCount(0))
-		streamGetter.EXPECT().GetOrOpenReceiveStream(protocol.StreamID(5)).Return(stream5, nil)
 		q.AddStream(5)
+		streamGetter.EXPECT().GetOrOpenReceiveStream(protocol.StreamID(5)).Return(stream5, nil)
+		q.QueueAll()
+		Expect(queuedFrames).To(BeEmpty())
+	})
+
+	It("removes streams for which the flow controller returns an offset of 0 from the queue", func() {
+		stream5 := NewMockStreamI(mockCtrl)
+		stream5.EXPECT().getWindowUpdate().Return(protocol.ByteCount(0))
+		q.AddStream(5)
+		streamGetter.EXPECT().GetOrOpenReceiveStream(protocol.StreamID(5)).Return(stream5, nil)
+		q.QueueAll()
+		Expect(queuedFrames).To(BeEmpty())
+		// don't EXPECT any further calls to GetOrOpenReveiveStream and to getWindowUpdate
 		q.QueueAll()
 		Expect(queuedFrames).To(BeEmpty())
 	})