From df55c30c86d373cfcbe47f9b8b498689232f335b Mon Sep 17 00:00:00 2001
From: Marten Seemann <martenseemann@gmail.com>
Date: Wed, 13 May 2020 11:58:24 +0700
Subject: [PATCH] add a function to tell if there's app data in the
 retransmission queue

---
 retransmission_queue.go      | 4 ++++
 retransmission_queue_test.go | 3 +++
 2 files changed, 7 insertions(+)

diff --git a/retransmission_queue.go b/retransmission_queue.go
index d29d3660b..404b72b79 100644
--- a/retransmission_queue.go
+++ b/retransmission_queue.go
@@ -47,6 +47,10 @@ func (q *retransmissionQueue) HasHandshakeData() bool {
 	return len(q.handshakeCryptoData) > 0 || len(q.handshake) > 0
 }
 
+func (q *retransmissionQueue) HasAppData() bool {
+	return len(q.appData) > 0
+}
+
 func (q *retransmissionQueue) AddAppData(f wire.Frame) {
 	if _, ok := f.(*wire.StreamFrame); ok {
 		panic("STREAM frames are handled with their respective streams.")
diff --git a/retransmission_queue_test.go b/retransmission_queue_test.go
index c9e940f01..213f732fb 100644
--- a/retransmission_queue_test.go
+++ b/retransmission_queue_test.go
@@ -176,9 +176,12 @@ var _ = Describe("Retransmission queue", func() {
 
 		It("queues and retrieves a control frame", func() {
 			f := &wire.MaxDataFrame{ByteOffset: 0x42}
+			Expect(q.HasAppData()).To(BeFalse())
 			q.AddAppData(f)
+			Expect(q.HasAppData()).To(BeTrue())
 			Expect(q.GetAppDataFrame(f.Length(version) - 1)).To(BeNil())
 			Expect(q.GetAppDataFrame(f.Length(version))).To(Equal(f))
+			Expect(q.HasAppData()).To(BeFalse())
 		})
 	})
 })