Refactor composing report blocks for rtcp Sender/Receiver reports

webrtc/modules/rtp_rtcp/source/rtcp_packet/receiver_report_unittest.cc

Index: webrtc/modules/rtp_rtcp/source/rtcp_packet/receiver_report_unittest.cc
diff --git a/webrtc/modules/rtp_rtcp/source/rtcp_packet/receiver_report_unittest.cc b/webrtc/modules/rtp_rtcp/source/rtcp_packet/receiver_report_unittest.cc
index 4061db889f2b39a0a2681f680722bc2ea2c08c43..4ead09eb3608c3d3967d04b96b977277d7926d98 100644
--- a/webrtc/modules/rtp_rtcp/source/rtcp_packet/receiver_report_unittest.cc
+++ b/webrtc/modules/rtp_rtcp/source/rtcp_packet/receiver_report_unittest.cc
@@ -127,4 +127,25 @@ TEST(RtcpPacketReceiverReportTest, CreateWithTooManyReportBlocks) {
   EXPECT_FALSE(rr.AddReportBlock(rb));
 }
 
+TEST(RtcpPacketReceiverReportTest, SetReportBlocksOverwritesOldBlocks) {

[eladalon, 2017/07/21 12:53:19]

nit: Checking by size only does not guarantee correctness completely. Suppose we
start with [1], and try to set([5, 6, 7]), I can imagine code that would
accidentally end up with [1, 6, 7], which would still pass the test. IMHO, it
wouldn't be overkill to check the members, too. Or is it difficult to do
comparison of the specific elements there?

[danilchap, 2017/07/21 17:11:14]

I lack imagination to see that code, but it's not too hard to check some values
in report blocks. Done.

+  ReceiverReport rr;
+  rr.AddReportBlock(ReportBlock());
+  ASSERT_EQ(rr.report_blocks().size(), 1u);
+
+  std::vector<ReportBlock> blocks(3);
+  EXPECT_TRUE(rr.SetReportBlocks(blocks));
+  EXPECT_EQ(rr.report_blocks().size(), 3u);
+}
+
+TEST(RtcpPacketReceiverReportTest, SetTooManyReportBlocks) {
+  ReceiverReport rr;
+  const size_t kMaxReportBlocks = (1 << 5) - 1;
+
+  std::vector<ReportBlock> blocks(kMaxReportBlocks);
+  EXPECT_TRUE(rr.SetReportBlocks(blocks));

[eladalon, 2017/07/21 12:53:19]

nit: Two tests here:
1. Max number of blocks accepted.
2. One more than max - rejected.

[danilchap, 2017/07/21 17:11:14]

renamed to document this test is about showing the limit.

+
+  blocks.push_back(ReportBlock());
+  EXPECT_FALSE(rr.SetReportBlocks(blocks));
+}
+
 }  // namespace webrtc