Ping connections with the fast rate until each connection is pinged at least three times.

webrtc/p2p/base/p2ptransportchannel_unittest.cc

Index: webrtc/p2p/base/p2ptransportchannel_unittest.cc
diff --git a/webrtc/p2p/base/p2ptransportchannel_unittest.cc b/webrtc/p2p/base/p2ptransportchannel_unittest.cc
index e2c50031268a8dd5025bc252a8b532317dfc5ced..30b1e452a6d73cc39fb3c6560bad75bf72e2ff7e 100644
--- a/webrtc/p2p/base/p2ptransportchannel_unittest.cc
+++ b/webrtc/p2p/base/p2ptransportchannel_unittest.cc
@@ -37,6 +37,7 @@ using cricket::kMinimumStepDelay;
 using cricket::kDefaultStepDelay;
 using cricket::PORTALLOCATOR_ENABLE_SHARED_SOCKET;
 using cricket::ServerAddresses;
+using cricket::kMinNumPingsSent;
 using rtc::SocketAddress;
 
 static const int kDefaultTimeout = 1000;
@@ -2126,6 +2127,28 @@ TEST_F(P2PTransportChannelPingTest, TestTriggeredChecks) {
   EXPECT_EQ(conn1, FindNextPingableConnectionAndPingIt(&ch));
 }
 
+TEST_F(P2PTransportChannelPingTest, TestAllConnectionsPingedSufficiently) {
+  cricket::FakePortAllocator pa(rtc::Thread::Current(), nullptr);
+  cricket::P2PTransportChannel ch("ping sufficiently", 1, &pa);
+  PrepareChannel(&ch);
+  ch.Connect();
+  ch.MaybeStartGathering();
+  ch.AddRemoteCandidate(CreateHostCandidate("1.1.1.1", 1, 1));
+  ch.AddRemoteCandidate(CreateHostCandidate("2.2.2.2", 2, 2));
+
+  cricket::Connection* conn1 = WaitForConnectionTo(&ch, "1.1.1.1", 1);
+  cricket::Connection* conn2 = WaitForConnectionTo(&ch, "2.2.2.2", 2);
+  ASSERT_TRUE(conn1 != nullptr);
+  ASSERT_TRUE(conn2 != nullptr);
+
+  // Low-priority connection becomes writable so that the other connection
+  // is not pruned.
+  conn1->ReceivedPingResponse();
+  EXPECT_TRUE_WAIT(conn1->num_pings_sent() >= kMinNumPingsSent &&
+                       conn2->num_pings_sent() >= kMinNumPingsSent,
+                   kDefaultTimeout);
+}
+
 TEST_F(P2PTransportChannelPingTest, TestNoTriggeredChecksWhenWritable) {
   cricket::FakePortAllocator pa(rtc::Thread::Current(), nullptr);
   cricket::P2PTransportChannel ch("trigger checks", 1, &pa);
@@ -2807,11 +2830,17 @@ TEST_F(P2PTransportChannelMostLikelyToWorkFirstTest,
   // Verify that conn3 will be the "best connection" since it is readable and
   // writable. After |MAX_CURRENT_STRONG_INTERVAL|, it should be the next
   // pingable connection.
+  /*
+   * We now ping the connection with fast rates until all connections
+   * are pinged three times. The following test becomes flaky because the
+   * best connection may have been pinged before |max_strong_interval|.
+   * Temporarily disable this until we use fake clock for the test.

[pthatcher1, 2016/05/25 17:29:13]

We should have a TODO to re-enable it.  

And could you use the comment style consistent with the rest of the file?

[honghaiz3, 2016/05/25 18:40:02]

Done for both.

   EXPECT_TRUE_WAIT(conn3 == ch.best_connection(), 5000);
   WAIT(false, max_strong_interval + 100);
   conn3->ReceivedPingResponse();
   ASSERT_TRUE(conn3->writable());
   EXPECT_EQ(conn3, FindNextPingableConnectionAndPingIt(&ch));
+  */
 }
 
 // Test that Relay/Relay connections will be pinged first when everything has