Adds an alarm for sending a QUIC FEC packet.

net/quic/quic_packet_generator_test.cc

 // Copyright (c) 2012 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_packet_generator.h"
 
 #include <string>
 
 #include "net/quic/crypto/crypto_protocol.h"
 #include "net/quic/crypto/null_encrypter.h"
@@ skipping 14 matching lines @@
 using testing::InSequence;
 using testing::Return;
 using testing::SaveArg;
 using testing::StrictMock;
 using testing::_;
 
 namespace net {
 namespace test {
 namespace {
 
+const int64 kMinFecTimeoutMs = 5u;
+
 class MockDelegate : public QuicPacketGenerator::DelegateInterface {
  public:
   MockDelegate() {}
   ~MockDelegate() override {}
 
   MOCK_METHOD3(ShouldGeneratePacket,
                bool(TransmissionType transmission_type,
                     HasRetransmittableData retransmittable,
                     IsHandshake handshake));
   MOCK_METHOD0(CreateAckFrame, QuicAckFrame*());
@@ skipping 25 matching lines @@
     EXPECT_CALL(*this, ShouldGeneratePacket(NOT_RETRANSMISSION,
                                             NO_RETRANSMITTABLE_DATA, _))
         .WillRepeatedly(Return(true));
   }
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MockDelegate);
 };
 
 // Simple struct for describing the contents of a packet.
-// Useful in conjunction with a SimpleQuicFrame for validating
-// that a packet contains the expected frames.
+// Useful in conjunction with a SimpleQuicFrame for validating that a packet
+// contains the expected frames.
 struct PacketContents {
   PacketContents()
       : num_ack_frames(0),
         num_connection_close_frames(0),
         num_feedback_frames(0),
         num_goaway_frames(0),
         num_rst_stream_frames(0),
         num_stop_waiting_frames(0),
         num_stream_frames(0),
         fec_group(0) {
@@ skipping 17 matching lines @@
   QuicPacketGeneratorTest()
       : framer_(QuicSupportedVersions(), QuicTime::Zero(), false),
         generator_(42, &framer_, &random_, &delegate_),
         creator_(QuicPacketGeneratorPeer::GetPacketCreator(&generator_)),
         packet_(0, PACKET_1BYTE_SEQUENCE_NUMBER, nullptr, 0, nullptr),
         packet2_(0, PACKET_1BYTE_SEQUENCE_NUMBER, nullptr, 0, nullptr),
         packet3_(0, PACKET_1BYTE_SEQUENCE_NUMBER, nullptr, 0, nullptr),
         packet4_(0, PACKET_1BYTE_SEQUENCE_NUMBER, nullptr, 0, nullptr),
         packet5_(0, PACKET_1BYTE_SEQUENCE_NUMBER, nullptr, 0, nullptr),
         packet6_(0, PACKET_1BYTE_SEQUENCE_NUMBER, nullptr, 0, nullptr),
-        packet7_(0, PACKET_1BYTE_SEQUENCE_NUMBER, nullptr, 0, nullptr) {}
+        packet7_(0, PACKET_1BYTE_SEQUENCE_NUMBER, nullptr, 0, nullptr),
+        packet8_(0, PACKET_1BYTE_SEQUENCE_NUMBER, nullptr, 0, nullptr) {}
 
   ~QuicPacketGeneratorTest() override {
     delete packet_.packet;
     delete packet_.retransmittable_frames;
     delete packet2_.packet;
     delete packet2_.retransmittable_frames;
     delete packet3_.packet;
     delete packet3_.retransmittable_frames;
     delete packet4_.packet;
     delete packet4_.retransmittable_frames;
     delete packet5_.packet;
     delete packet5_.retransmittable_frames;
     delete packet6_.packet;
     delete packet6_.retransmittable_frames;
     delete packet7_.packet;
     delete packet7_.retransmittable_frames;
+    delete packet8_.packet;
+    delete packet8_.retransmittable_frames;
   }
 
   QuicAckFrame* CreateAckFrame() {
     // TODO(rch): Initialize this so it can be verified later.
     return new QuicAckFrame(MakeAckFrame(0));
   }
 
   QuicCongestionFeedbackFrame* CreateFeedbackFrame() {
     QuicCongestionFeedbackFrame* frame = new QuicCongestionFeedbackFrame;
     frame->type = kTCP;
@@ skipping 83 matching lines @@
   QuicPacketGenerator generator_;
   QuicPacketCreator* creator_;
   SimpleQuicFramer simple_framer_;
   SerializedPacket packet_;
   SerializedPacket packet2_;
   SerializedPacket packet3_;
   SerializedPacket packet4_;
   SerializedPacket packet5_;
   SerializedPacket packet6_;
   SerializedPacket packet7_;
+  SerializedPacket packet8_;
 
  private:
   scoped_ptr<char[]> data_array_;
 };
 
 class MockDebugDelegate : public QuicPacketGenerator::DebugDelegate {
  public:
   MOCK_METHOD1(OnFrameAddedToPacket,
                void(const QuicFrame&));
 };
@@ skipping 217 matching lines @@
   // Now both frames will be flushed out.
   EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(SaveArg<0>(&packet_));
   generator_.FinishBatchOperations();
   EXPECT_FALSE(generator_.HasQueuedFrames());
 
   PacketContents contents;
   contents.num_stream_frames = 2;
   CheckPacketContains(contents, packet_);
 }
 
-TEST_F(QuicPacketGeneratorTest, ConsumeDataFEC) {
+TEST_F(QuicPacketGeneratorTest, ConsumeDataSendsFecOnMaxGroupSize) {
   delegate_.SetCanWriteAnything();
 
   // Send FEC every two packets.
   creator_->set_max_packets_per_fec_group(2);
 
   {
     InSequence dummy;
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet_));
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet2_));
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet3_));
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet4_));
-    EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
-        SaveArg<0>(&packet5_));
   }
 
-  // Send enough data to create 3 packets: two full and one partial. Send
-  // with MUST_FEC_PROTECT flag.
+  // Send enough data to create 3 packets: two full and one partial. Send with
+  // MUST_FEC_PROTECT flag.
   size_t data_len = 2 * kDefaultMaxPacketSize + 100;
   QuicConsumedData consumed = generator_.ConsumeData(
       3, CreateData(data_len), 0, true, MUST_FEC_PROTECT, nullptr);
   EXPECT_EQ(data_len, consumed.bytes_consumed);
   EXPECT_TRUE(consumed.fin_consumed);
   EXPECT_FALSE(generator_.HasQueuedFrames());
 
   CheckPacketHasSingleStreamFrame(packet_);
   CheckPacketHasSingleStreamFrame(packet2_);
   CheckPacketIsFec(packet3_, 1);
+  CheckPacketHasSingleStreamFrame(packet4_);
+  EXPECT_TRUE(creator_->IsFecProtected());
 
-  CheckPacketHasSingleStreamFrame(packet4_);
-  CheckPacketIsFec(packet5_, 4);
+  // The FEC packet under construction will be sent when one more packet is sent
+  // (since FEC group size is 2), or when OnFecTimeout is called. Send more data
+  // with MAY_FEC_PROTECT. This packet should also be protected, and FEC packet
+  // is sent since FEC group size is reached.
+  {
+    InSequence dummy;
+    EXPECT_CALL(delegate_, OnSerializedPacket(_))
+        .WillOnce(SaveArg<0>(&packet5_));
+    EXPECT_CALL(delegate_, OnSerializedPacket(_))
+        .WillOnce(SaveArg<0>(&packet6_));
+  }
+  consumed = generator_.ConsumeData(5, CreateData(1u), 0, true, MAY_FEC_PROTECT,
+                                    nullptr);
+  EXPECT_EQ(1u, consumed.bytes_consumed);
+  CheckPacketHasSingleStreamFrame(packet5_);
+  CheckPacketIsFec(packet6_, 4);
+  EXPECT_FALSE(creator_->IsFecProtected());
 }
 
-TEST_F(QuicPacketGeneratorTest, ConsumeDataSendsFecAtEnd) {
+TEST_F(QuicPacketGeneratorTest, ConsumeDataSendsFecOnTimeout) {
   delegate_.SetCanWriteAnything();
+  creator_->set_max_packets_per_fec_group(1000);
 
-  // Enable FEC.
+  // Send data with MUST_FEC_PROTECT flag. No FEC packet is emitted, but the
+  // creator FEC protects all data.
+  EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(SaveArg<0>(&packet_));
+  QuicConsumedData consumed = generator_.ConsumeData(3, CreateData(1u), 0, true,
+                                                     MUST_FEC_PROTECT, nullptr);
+  EXPECT_EQ(1u, consumed.bytes_consumed);
+  EXPECT_TRUE(consumed.fin_consumed);
+  CheckPacketHasSingleStreamFrame(packet_);
+  EXPECT_TRUE(creator_->IsFecProtected());
+
+  // Send more data with MAY_FEC_PROTECT. This packet should also be protected,
+  // and FEC packet is not yet sent.
+  EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(SaveArg<0>(&packet2_));
+  consumed = generator_.ConsumeData(5, CreateData(1u), 0, true, MAY_FEC_PROTECT,
+                                    nullptr);
+  EXPECT_EQ(1u, consumed.bytes_consumed);
+  CheckPacketHasSingleStreamFrame(packet2_);
+  EXPECT_TRUE(creator_->IsFecProtected());
+
+  // Calling OnFecTimeout should cause the FEC packet to be emitted.
+  EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(SaveArg<0>(&packet3_));
+  generator_.OnFecTimeout();
+  CheckPacketIsFec(packet3_, 1);
+  EXPECT_FALSE(creator_->IsFecProtected());
+
+  // Subsequent data is protected under the next FEC group. Send enough data to
+  // create 2 more packets: one full and one partial.
+  {
+    InSequence dummy;
+    EXPECT_CALL(delegate_, OnSerializedPacket(_))
+        .WillOnce(SaveArg<0>(&packet4_));
+    EXPECT_CALL(delegate_, OnSerializedPacket(_))
+        .WillOnce(SaveArg<0>(&packet5_));
+  }
+  size_t data_len = kDefaultMaxPacketSize + 1;
+  consumed = generator_.ConsumeData(7, CreateData(data_len), 0, true,
+                                    MUST_FEC_PROTECT, nullptr);
+  EXPECT_EQ(data_len, consumed.bytes_consumed);
+  EXPECT_TRUE(consumed.fin_consumed);
+  CheckPacketHasSingleStreamFrame(packet4_);
+  CheckPacketHasSingleStreamFrame(packet5_);
+  EXPECT_TRUE(creator_->IsFecProtected());
+
+  // Calling OnFecTimeout should cause the FEC packet to be emitted.
+  EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(SaveArg<0>(&packet6_));
+  generator_.OnFecTimeout();
+  CheckPacketIsFec(packet6_, 4);
+  EXPECT_FALSE(creator_->IsFecProtected());
+}
+
+TEST_F(QuicPacketGeneratorTest, GetFecTimeoutFiniteOnlyOnFirstPacketInGroup) {
+  delegate_.SetCanWriteAnything();
   creator_->set_max_packets_per_fec_group(6);
+
+  // Send enough data to create 2 packets: one full and one partial. Send with
+  // MUST_FEC_PROTECT flag. No FEC packet is emitted yet, but the creator FEC
+  // protects all data.
   {
     InSequence dummy;
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet_));
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet2_));
-    EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
-        SaveArg<0>(&packet3_));
   }
-
-  // Send enough data to create 2 packets: one full and one partial. Send
-  // with MUST_FEC_PROTECT flag.
   size_t data_len = 1 * kDefaultMaxPacketSize + 100;
   QuicConsumedData consumed = generator_.ConsumeData(
       3, CreateData(data_len), 0, true, MUST_FEC_PROTECT, nullptr);
   EXPECT_EQ(data_len, consumed.bytes_consumed);
   EXPECT_TRUE(consumed.fin_consumed);
   EXPECT_FALSE(generator_.HasQueuedFrames());
-
   CheckPacketHasSingleStreamFrame(packet_);
   CheckPacketHasSingleStreamFrame(packet2_);
-  CheckPacketIsFec(packet3_, 1);
+  EXPECT_TRUE(creator_->IsFecProtected());
+
+  // GetFecTimeout returns finite timeout only for first packet in group.
+  EXPECT_EQ(QuicTime::Delta::FromMilliseconds(kMinFecTimeoutMs),
+            generator_.GetFecTimeout(/*sequence_number=*/1u));
+  EXPECT_EQ(QuicTime::Delta::Infinite(),
+            generator_.GetFecTimeout(/*sequence_number=*/2u));
+
+  // Send more data with MAY_FEC_PROTECT. This packet should also be protected,
+  // and FEC packet is not yet sent.
+  EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(SaveArg<0>(&packet3_));
+  consumed = generator_.ConsumeData(5, CreateData(1u), 0, true, MAY_FEC_PROTECT,
+                                    nullptr);
+  CheckPacketHasSingleStreamFrame(packet3_);
+  EXPECT_TRUE(creator_->IsFecProtected());
+
+  // GetFecTimeout returns finite timeout only for first packet in group.
+  EXPECT_EQ(QuicTime::Delta::Infinite(),
+            generator_.GetFecTimeout(/*sequence_number=*/3u));
+
+  // Calling OnFecTimeout should cause the FEC packet to be emitted.
+  EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(SaveArg<0>(&packet4_));
+  generator_.OnFecTimeout();
+  CheckPacketIsFec(packet4_, /*fec_group=*/1u);
+  EXPECT_FALSE(creator_->IsFecProtected());
+
+  // Subsequent data is protected under the next FEC group. Send enough data to
+  // create 2 more packets: one full and one partial.
+  {
+    InSequence dummy;
+    EXPECT_CALL(delegate_, OnSerializedPacket(_))
+        .WillOnce(SaveArg<0>(&packet5_));
+    EXPECT_CALL(delegate_, OnSerializedPacket(_))
+        .WillOnce(SaveArg<0>(&packet6_));
+  }
+  data_len = kDefaultMaxPacketSize + 1u;
+  consumed = generator_.ConsumeData(7, CreateData(data_len), 0, true,
+                                    MUST_FEC_PROTECT, nullptr);
+  EXPECT_EQ(data_len, consumed.bytes_consumed);
+  EXPECT_TRUE(consumed.fin_consumed);
+  CheckPacketHasSingleStreamFrame(packet5_);
+  CheckPacketHasSingleStreamFrame(packet6_);
+  EXPECT_TRUE(creator_->IsFecProtected());
+
+  // GetFecTimeout returns finite timeout for first packet in the new group.
+  EXPECT_EQ(QuicTime::Delta::FromMilliseconds(kMinFecTimeoutMs),
+            generator_.GetFecTimeout(/*sequence_number=*/5u));
+  EXPECT_EQ(QuicTime::Delta::Infinite(),
+            generator_.GetFecTimeout(/*sequence_number=*/6u));
+
+  // Calling OnFecTimeout should cause the FEC packet to be emitted.
+  EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(SaveArg<0>(&packet7_));
+  generator_.OnFecTimeout();
+  CheckPacketIsFec(packet7_, /*fec_group=*/5u);
+  EXPECT_FALSE(creator_->IsFecProtected());
+
+  // Send more data with MAY_FEC_PROTECT. No FEC protection, so GetFecTimeout
+  // returns infinite.
+  EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(SaveArg<0>(&packet8_));
+  consumed = generator_.ConsumeData(9, CreateData(1u), 0, true, MAY_FEC_PROTECT,
+                                    nullptr);
+  CheckPacketHasSingleStreamFrame(packet8_);
+  EXPECT_FALSE(creator_->IsFecProtected());
+  EXPECT_EQ(QuicTime::Delta::Infinite(),
+            generator_.GetFecTimeout(/*sequence_number=*/8u));
 }
 
 TEST_F(QuicPacketGeneratorTest, ConsumeData_FramesPreviouslyQueued) {
   // Set the packet size be enough for two stream frames with 0 stream offset,
   // but not enough for a stream frame of 0 offset and one with non-zero offset.
   size_t length =
       NullEncrypter().GetCiphertextSize(0) +
-      GetPacketHeaderSize(creator_->connection_id_length(),
-                          true,
+      GetPacketHeaderSize(creator_->connection_id_length(), true,
                           creator_->next_sequence_number_length(),
                           NOT_IN_FEC_GROUP) +
       // Add an extra 3 bytes for the payload and 1 byte so BytesFree is larger
       // than the GetMinStreamFrameSize.
       QuicFramer::GetMinStreamFrameSize(1, 0, false, NOT_IN_FEC_GROUP) + 3 +
       QuicFramer::GetMinStreamFrameSize(1, 0, true, NOT_IN_FEC_GROUP) + 1;
   creator_->set_max_packet_length(length);
   delegate_.SetCanWriteAnything();
   {
      InSequence dummy;
@@ skipping 20 matching lines @@
   EXPECT_EQ(3u, consumed.bytes_consumed);
   EXPECT_TRUE(consumed.fin_consumed);
   EXPECT_FALSE(generator_.HasQueuedFrames());
 
   PacketContents contents;
   contents.num_stream_frames = 1;
   CheckPacketContains(contents, packet_);
   CheckPacketContains(contents, packet2_);
 }
 
+TEST_F(QuicPacketGeneratorTest, NoFecPacketSentWhenBatchEnds) {
+  delegate_.SetCanWriteAnything();
+  creator_->set_max_packets_per_fec_group(6);
+
+  generator_.StartBatchOperations();
+
+  generator_.ConsumeData(3, MakeIOVector("foo"), 2, true, MUST_FEC_PROTECT,
+                         nullptr);
+  QuicConsumedData consumed = generator_.ConsumeData(
+      5, MakeIOVector("quux"), 7, false, MUST_FEC_PROTECT, nullptr);
+  EXPECT_EQ(4u, consumed.bytes_consumed);
+  EXPECT_FALSE(consumed.fin_consumed);
+  EXPECT_TRUE(generator_.HasQueuedFrames());
+
+  // Now both frames will be flushed out, but FEC packet is not yet sent.
+  EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(SaveArg<0>(&packet_));
+  generator_.FinishBatchOperations();
+  EXPECT_FALSE(generator_.HasQueuedFrames());
+
+  PacketContents contents;
+  contents.num_stream_frames = 2u;
+  contents.fec_group = 1u;
+  CheckPacketContains(contents, packet_);
+
+  // Forcing FEC timeout causes FEC packet to be emitted.
+  EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(SaveArg<0>(&packet2_));
+  generator_.OnFecTimeout();
+  CheckPacketIsFec(packet2_, /*fec_group=*/1u);
+}
+
 TEST_F(QuicPacketGeneratorTest, FecTimeoutOnRttChange) {
-  EXPECT_EQ(QuicTime::Delta::Zero(), generator_.fec_timeout());
+  EXPECT_EQ(QuicTime::Delta::Zero(),
+            QuicPacketGeneratorPeer::GetFecTimeout(&generator_));
   generator_.OnRttChange(QuicTime::Delta::FromMilliseconds(300));
-  EXPECT_EQ(QuicTime::Delta::FromMilliseconds(150), generator_.fec_timeout());
+  EXPECT_EQ(QuicTime::Delta::FromMilliseconds(150),
+            QuicPacketGeneratorPeer::GetFecTimeout(&generator_));
 }
 
 TEST_F(QuicPacketGeneratorTest, FecGroupSizeOnCongestionWindowChange) {
   delegate_.SetCanWriteAnything();
   creator_->set_max_packets_per_fec_group(50);
   EXPECT_EQ(50u, creator_->max_packets_per_fec_group());
   EXPECT_FALSE(creator_->IsFecGroupOpen());
 
   // On reduced cwnd.
   generator_.OnCongestionWindowChange(7);
   EXPECT_EQ(3u, creator_->max_packets_per_fec_group());
 
   // On increased cwnd.
   generator_.OnCongestionWindowChange(100);
   EXPECT_EQ(50u, creator_->max_packets_per_fec_group());
 
   // On collapsed cwnd.
   generator_.OnCongestionWindowChange(1);
   EXPECT_EQ(2u, creator_->max_packets_per_fec_group());
 }
 
 TEST_F(QuicPacketGeneratorTest, FecGroupSizeChangeWithOpenGroup) {
   delegate_.SetCanWriteAnything();
-  // TODO(jri): This starting of batch mode should not be required when
-  // FEC sending is separated from batching operations.
   generator_.StartBatchOperations();
   creator_->set_max_packets_per_fec_group(50);
   EXPECT_EQ(50u, creator_->max_packets_per_fec_group());
   EXPECT_FALSE(creator_->IsFecGroupOpen());
 
-  // Send enough data to create 4 packets with MUST_FEC_PROTECT flag.
-  // 3 packets are sent, one is queued in the creator.
+  // Send enough data to create 4 packets with MUST_FEC_PROTECT flag. 3 packets
+  // are sent, one is queued in the creator.
   {
     InSequence dummy;
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet_));
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet2_));
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet3_));
   }
   size_t data_len = 3 * kDefaultMaxPacketSize + 1;
   QuicConsumedData consumed = generator_.ConsumeData(
       7, CreateData(data_len), 0, true, MUST_FEC_PROTECT, nullptr);
   EXPECT_EQ(data_len, consumed.bytes_consumed);
   EXPECT_TRUE(creator_->IsFecGroupOpen());
 
   // Change FEC groupsize.
   generator_.OnCongestionWindowChange(2);
   EXPECT_EQ(2u, creator_->max_packets_per_fec_group());
 
-  // Send enough data to trigger one unprotected data packet,
-  // causing the FEC packet to also be sent.
+  // Send enough data to trigger one unprotected data packet, causing the FEC
+  // packet to also be sent.
   {
     InSequence dummy;
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet4_));
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet5_));
   }
   consumed = generator_.ConsumeData(7, CreateData(kDefaultMaxPacketSize), 0,
                                     true, MAY_FEC_PROTECT, nullptr);
   EXPECT_EQ(kDefaultMaxPacketSize, consumed.bytes_consumed);
@@ skipping 24 matching lines @@
   {
     InSequence dummy;
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet2_));
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet3_));
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet4_));
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet5_));
-    EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
-        SaveArg<0>(&packet6_));
   }
   // Send enough data to create 3 packets with MUST_FEC_PROTECT flag.
   size_t data_len = 2 * kDefaultMaxPacketSize + 100;
   consumed = generator_.ConsumeData(7, CreateData(data_len), 0, true,
                                     MUST_FEC_PROTECT, nullptr);
   EXPECT_EQ(data_len, consumed.bytes_consumed);
   EXPECT_FALSE(generator_.HasQueuedFrames());
 
-  // Verify that two FEC packets were sent.
+  // Verify that packets sent were 3 data and 1 FEC.
   CheckPacketHasSingleStreamFrame(packet2_);
   CheckPacketHasSingleStreamFrame(packet3_);
   CheckPacketIsFec(packet4_, /*fec_group=*/2u);
   CheckPacketHasSingleStreamFrame(packet5_);
-  CheckPacketIsFec(packet6_, /*fec_group=*/5u);  // Sent at the end of stream.
+
+  // Calling OnFecTimeout should emit the pending FEC packet.
+  EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(SaveArg<0>(&packet6_));
+  generator_.OnFecTimeout();
+  CheckPacketIsFec(packet6_, /*fec_group=*/5u);
 
   // Send one unprotected data packet.
   EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet7_));
   consumed = generator_.ConsumeData(7, CreateData(1u), 0, true, MAY_FEC_PROTECT,
                                     nullptr);
   EXPECT_EQ(1u, consumed.bytes_consumed);
   EXPECT_FALSE(generator_.HasQueuedFrames());
   EXPECT_FALSE(creator_->IsFecProtected());
   // Verify that one unprotected data packet was sent.
@@ skipping 97 matching lines @@
   EXPECT_TRUE(creator_->IsFecProtected());
 }
 
 TEST_F(QuicPacketGeneratorTest, SwitchFecOnOffWithSubsequentPacketsProtected) {
   delegate_.SetCanWriteAnything();
 
   // Enable FEC.
   creator_->set_max_packets_per_fec_group(2);
   EXPECT_FALSE(creator_->IsFecProtected());
 
-  generator_.StartBatchOperations();
   // Send first packet, FEC protected.
   EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(SaveArg<0>(&packet_));
-  // Write enough data to cause a packet to be emitted.
-  size_t data_len = kDefaultMaxPacketSize;
-  QuicConsumedData consumed = generator_.ConsumeData(
-      5, CreateData(data_len), 0, true, MUST_FEC_PROTECT, nullptr);
-  EXPECT_EQ(data_len, consumed.bytes_consumed);
+  QuicConsumedData consumed = generator_.ConsumeData(5, CreateData(1u), 0, true,
+                                                     MUST_FEC_PROTECT, nullptr);
+  EXPECT_EQ(1u, consumed.bytes_consumed);
   PacketContents contents;
   contents.num_stream_frames = 1u;
   contents.fec_group = 1u;
   CheckPacketContains(contents, packet_);
 
   // FEC should still be on in creator.
   EXPECT_TRUE(creator_->IsFecProtected());
 
-  // Send enough unprotected data to cause second packet to be sent, which gets
+  // Send unprotected data to cause second packet to be sent, which gets
   // protected because it happens to fall within an open FEC group. Data packet
   // will be followed by FEC packet.
   {
     InSequence dummy;
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet2_));
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet3_));
   }
-  consumed = generator_.ConsumeData(5, CreateData(data_len), 0, true,
-                                    MAY_FEC_PROTECT, nullptr);
-  EXPECT_EQ(data_len, consumed.bytes_consumed);
-  contents.num_stream_frames = 2u;
+  consumed = generator_.ConsumeData(5, CreateData(1u), 0, true, MAY_FEC_PROTECT,
+                                    nullptr);
+  EXPECT_EQ(1u, consumed.bytes_consumed);
+  contents.num_stream_frames = 1u;
   CheckPacketContains(contents, packet2_);
   CheckPacketIsFec(packet3_, /*fec_group=*/1u);
 
   // FEC protection should be off in creator.
   EXPECT_FALSE(creator_->IsFecProtected());
 }
 
 TEST_F(QuicPacketGeneratorTest, SwitchFecOnOffThenOnWithCreatorProtectionOn) {
   delegate_.SetCanWriteAnything();
   generator_.StartBatchOperations();
@@ skipping 45 matching lines @@
   delegate_.SetCanNotWrite();
 
   generator_.SetShouldSendAck(true, false);
   generator_.AddControlFrame(QuicFrame(CreateRstStreamFrame()));
   EXPECT_TRUE(generator_.HasQueuedFrames());
 
   delegate_.SetCanWriteAnything();
 
   generator_.StartBatchOperations();
 
-  // When the first write operation is invoked, the ack and feedback
-  // frames will be returned.
+  // When the first write operation is invoked, the ack and feedback frames will
+  // be returned.
   EXPECT_CALL(delegate_, CreateAckFrame()).WillOnce(Return(CreateAckFrame()));
   EXPECT_CALL(delegate_, CreateFeedbackFrame()).WillOnce(
       Return(CreateFeedbackFrame()));
 
   // Send some data and a control frame
   generator_.ConsumeData(3, MakeIOVector("quux"), 7, false, MAY_FEC_PROTECT,
                          nullptr);
   generator_.AddControlFrame(QuicFrame(CreateGoAwayFrame()));
 
   // All five frames will be flushed out in a single packet.
@@ skipping 14 matching lines @@
   delegate_.SetCanNotWrite();
 
   generator_.SetShouldSendAck(true, false);
   generator_.AddControlFrame(QuicFrame(CreateRstStreamFrame()));
   EXPECT_TRUE(generator_.HasQueuedFrames());
 
   delegate_.SetCanWriteAnything();
 
   generator_.StartBatchOperations();
 
-  // When the first write operation is invoked, the ack and feedback
-  // frames will be returned.
+  // When the first write operation is invoked, the ack and feedback frames will
+  // be returned.
   EXPECT_CALL(delegate_, CreateAckFrame()).WillOnce(Return(CreateAckFrame()));
   EXPECT_CALL(delegate_, CreateFeedbackFrame()).WillOnce(
       Return(CreateFeedbackFrame()));
 
   {
     InSequence dummy;
     // All five frames will be flushed out in a single packet
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
         SaveArg<0>(&packet_));
     EXPECT_CALL(delegate_, OnSerializedPacket(_)).WillOnce(
@@ skipping 44 matching lines @@
   generator_.SetConnectionIdLength(7);
   EXPECT_EQ(PACKET_8BYTE_CONNECTION_ID, creator_->connection_id_length());
   generator_.SetConnectionIdLength(8);
   EXPECT_EQ(PACKET_8BYTE_CONNECTION_ID, creator_->connection_id_length());
   generator_.SetConnectionIdLength(9);
   EXPECT_EQ(PACKET_8BYTE_CONNECTION_ID, creator_->connection_id_length());
 }
 
 }  // namespace test
 }  // namespace net