Making candidate pool size behave as decided in JSEP.

webrtc/pc/peerconnectioninterface_unittest.cc

 /*
  *  Copyright 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 2260 matching lines @@
   EXPECT_TRUE(pc_->SetConfiguration(config));
 
   // Set local answer; now it's too late.
   CreateAnswerAsLocalDescription();
   config.ice_candidate_pool_size = 3;
   RTCError error;
   EXPECT_FALSE(pc_->SetConfiguration(config, &error));
   EXPECT_EQ(RTCErrorType::INVALID_MODIFICATION, error.type());
 }
 
+// Test that after setting an answer, extra pooled sessions are discarded. The
+// ICE candidate pool is only intended to be used for the first offer/answer.
+TEST_F(PeerConnectionInterfaceTest,
+       ExtraPooledSessionsDiscardedAfterApplyingAnswer) {
+  CreatePeerConnection();
+
+  // Set a larger-than-necessary size.
+  PeerConnectionInterface::RTCConfiguration config;
+  config.ice_candidate_pool_size = 4;
+  EXPECT_TRUE(pc_->SetConfiguration(config));
+
+  // Do offer/answer.
+  CreateOfferAsRemoteDescription();
+  CreateAnswerAsLocalDescription();
+
+  // Expect no pooled sessions to be left.
+  const cricket::PortAllocatorSession* session =
+      port_allocator_->GetPooledSession();
+  EXPECT_EQ(nullptr, session);
+}
+
+// After Close is called, pooled candidates should be discarded so as to not
+// waste network resources.
+TEST_F(PeerConnectionInterfaceTest, PooledSessionsDiscardedAfterClose) {
+  CreatePeerConnection();
+
+  PeerConnectionInterface::RTCConfiguration config;
+  config.ice_candidate_pool_size = 3;
+  EXPECT_TRUE(pc_->SetConfiguration(config));
+  pc_->Close();
+
+  // Expect no pooled sessions to be left.
+  const cricket::PortAllocatorSession* session =
+      port_allocator_->GetPooledSession();
+  EXPECT_EQ(nullptr, session);
+}
+
 // Test that SetConfiguration returns an invalid modification error if
 // modifying a field in the configuration that isn't allowed to be modified.
 TEST_F(PeerConnectionInterfaceTest,
        SetConfigurationReturnsInvalidModificationError) {
   PeerConnectionInterface::RTCConfiguration config;
   config.bundle_policy = PeerConnectionInterface::kBundlePolicyBalanced;
   config.rtcp_mux_policy = PeerConnectionInterface::kRtcpMuxPolicyNegotiate;
   config.continual_gathering_policy = PeerConnectionInterface::GATHER_ONCE;
   CreatePeerConnection(config, nullptr);
 
@@ skipping 1118 matching lines @@
   EXPECT_NE(a, f);
 
   PeerConnectionInterface::RTCConfiguration g;
   g.disable_ipv6 = true;
   EXPECT_NE(a, g);
 
   PeerConnectionInterface::RTCConfiguration h(
       PeerConnectionInterface::RTCConfigurationType::kAggressive);
   EXPECT_NE(a, h);
 }