Fix a bug in QuicSentPacketManager::ClearPreviousRetransmissions where

net/quic/quic_sent_packet_manager_test.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/quic/quic_sent_packet_manager.h"
 
 #include "base/stl_util.h"
 #include "net/quic/test_tools/quic_sent_packet_manager_peer.h"
 #include "net/quic/test_tools/quic_test_utils.h"
 #include "testing/gmock/include/gmock/gmock.h"
@@ skipping 370 matching lines @@
   received_info.is_truncated = true;
   manager_.OnIncomingAck(received_info, QuicTime::Zero());
 
   // High water mark will be raised.
   QuicPacketSequenceNumber unacked[] = { 2, 3, 4 };
   VerifyUnackedPackets(unacked, arraysize(unacked));
   QuicPacketSequenceNumber retransmittable[] = { 4 };
   VerifyRetransmittablePackets(retransmittable, arraysize(retransmittable));
 }
 
+TEST_F(QuicSentPacketManagerTest, AckPreviousTransmissionThenTruncatedAck) {
+  SerializedPacket serialized_packet(CreateDataPacket(1));
+
+  manager_.OnSerializedPacket(serialized_packet);
+  RetransmitPacket(1, 2);
+  RetransmitPacket(2, 3);
+  RetransmitPacket(3, 4);
+  manager_.OnSerializedPacket(CreateDataPacket(5));
+  manager_.OnSerializedPacket(CreateDataPacket(6));
+  manager_.OnSerializedPacket(CreateDataPacket(7));
+  manager_.OnSerializedPacket(CreateDataPacket(8));
+  manager_.OnSerializedPacket(CreateDataPacket(9));
+
+  // Ack previous transmission
+  {
+    ReceivedPacketInfo received_info;
+    received_info.largest_observed = 2;
+    received_info.missing_packets.insert(1);
+    manager_.OnIncomingAck(received_info, QuicTime::Zero());
+    EXPECT_TRUE(manager_.IsUnacked(4));
+  }
+
+  // Truncated ack with 4 NACKs
+  {
+    ReceivedPacketInfo received_info;
+    received_info.largest_observed = 6;
+    received_info.missing_packets.insert(3);
+    received_info.missing_packets.insert(4);
+    received_info.missing_packets.insert(5);
+    received_info.missing_packets.insert(6);
+    received_info.is_truncated = true;
+    manager_.OnIncomingAck(received_info, QuicTime::Zero());
+  }
+
+  // High water mark will be raised.
+  QuicPacketSequenceNumber unacked[] = { 5, 6, 7, 8, 9 };
+  VerifyUnackedPackets(unacked, arraysize(unacked));
+  QuicPacketSequenceNumber retransmittable[] = { 5, 6, 7, 8, 9 };
+  VerifyRetransmittablePackets(retransmittable, arraysize(retransmittable));
+}
+
 TEST_F(QuicSentPacketManagerTest, SendDropAckRetransmitManyPackets) {
   manager_.OnSerializedPacket(CreateDataPacket(1));
   manager_.OnSerializedPacket(CreateDataPacket(2));
   manager_.OnSerializedPacket(CreateDataPacket(3));
 
   {
     // Ack packets 1 and 3.
     ReceivedPacketInfo received_info;
     received_info.largest_observed = 3;
     received_info.missing_packets.insert(2);
@@ skipping 723 matching lines @@
     delay = delay.Add(delay);
     EXPECT_CALL(*send_algorithm_, OnRetransmissionTimeout(true));
     manager_.OnRetransmissionTimeout();
     RetransmitNextPacket(i + 2);
   }
 }
 
 }  // namespace
 }  // namespace test
 }  // namespace net