Process incoming IQs in the same order that they were sent.

remoting/signaling/fake_signal_strategy.cc

 // Copyright 2014 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 "remoting/signaling/fake_signal_strategy.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/location.h"
@@ skipping 45 matching lines @@
                    base::Unretained(peer),
                    peer_callback));
   }
 }
 
 void FakeSignalStrategy::SetLocalJid(const std::string& jid) {
   DCHECK(CalledOnValidThread());
   jid_ = jid;
 }
 
+void FakeSignalStrategy::SimulatePackgeReordering() {
+  DCHECK(CalledOnValidThread());
+  simulate_reorder_ = true;
+}
+
 void FakeSignalStrategy::Connect() {
   DCHECK(CalledOnValidThread());
   FOR_EACH_OBSERVER(Listener, listeners_,
                     OnSignalStrategyStateChange(CONNECTED));
 }
 
 void FakeSignalStrategy::Disconnect() {
   DCHECK(CalledOnValidThread());
   FOR_EACH_OBSERVER(Listener, listeners_,
                     OnSignalStrategyStateChange(DISCONNECTED));
@@ skipping 52 matching lines @@
     std::unique_ptr<buzz::XmlElement> stanza) {
   thread->PostTask(FROM_HERE,
                    base::Bind(&FakeSignalStrategy::OnIncomingMessage,
                               target, base::Passed(&stanza)));
 }
 
 void FakeSignalStrategy::OnIncomingMessage(
     std::unique_ptr<buzz::XmlElement> stanza) {
   DCHECK(CalledOnValidThread());
 
+  if (!simulate_reorder_) {
+    NotifyListeners(std::move(stanza));
+    return;
+  }
+
+  // Simulate IQ message re-ordering by swapping the delivery order of the 2nd
+  // session-info message and the first transport-info message.
+  const buzz::XmlElement* jingle =
+      stanza->FirstNamed(buzz::QName("urn:xmpp:jingle:1", "jingle"));
+  std::string action = jingle->Attr(buzz::QName("", "action"));
+
+  if (action != "session-info" && action != "transport-info") {

[Sergey Ulanov, 2016/10/19 21:23:39]

I don't think we really need this logic here. The test could work as follows:
 1. Initialize connection.
 2. Call SimulatePackgeReordering().
 3. Send a set of transport messages and verify that they are received in
correct order.

[kelvinp, 2016/10/21 00:26:03]

Done.

+    NotifyListeners(std::move(stanza));
+    return;
+  }
+
+  if (action == "session-info") {
+    session_info_counts_++;
+    // Only reorder the 2nd session-info message.
+    if (session_info_counts_ == 2) {
+      pending_session_info_ = std::move(stanza);
+    } else {
+      NotifyListeners(std::move(stanza));
+    }
+  } else if (action == "transport-info" && session_info_counts_ == 2) {
+    NotifyListeners(std::move(stanza));
+    NotifyListeners(std::move(pending_session_info_));
+    pending_session_info_.reset();
+    simulate_reorder_ = false;
+  }
+}
+
+void FakeSignalStrategy::NotifyListeners(
+    std::unique_ptr<buzz::XmlElement> stanza) {
+  DCHECK(CalledOnValidThread());
+
   buzz::XmlElement* stanza_ptr = stanza.get();
   received_messages_.push_back(stanza.release());
 
   const std::string& to_field = stanza_ptr->Attr(buzz::QN_TO);
   if (to_field != jid_) {
     LOG(WARNING) << "Dropping stanza that is addressed to " << to_field
                  << ". Local jid: " << jid_
                  << ". Message content: " << stanza_ptr->Str();
     return;
   }
 
   base::ObserverListBase<Listener>::Iterator it(&listeners_);
   Listener* listener;
   while ((listener = it.GetNext()) != nullptr) {
     if (listener->OnSignalStrategyIncomingStanza(stanza_ptr))
       break;
   }
 }
 
 void FakeSignalStrategy::SetPeerCallback(const PeerCallback& peer_callback) {
   peer_callback_ = peer_callback;
 }
 
 }  // namespace remoting