Display isolate message queue in Observatory debugger

runtime/vm/message_test.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/assert.h"
 #include "vm/message.h"
 #include "vm/unit_test.h"
 
 namespace dart {
 
 
 static uint8_t* AllocMsg(const char* str) {
   return reinterpret_cast<uint8_t*>(strdup(str));
 }
 
 
 TEST_CASE(MessageQueue_BasicOperations) {
   MessageQueue queue;
   EXPECT(queue.IsEmpty());
+  MessageQueue::Iterator it(&queue);
+  // Queue is empty.
+  EXPECT(!it.HasNext());
 
   Dart_Port port = 1;
 
   const char* str1 = "msg1";
   const char* str2 = "msg2";
   const char* str3 = "msg3";
   const char* str4 = "msg4";
   const char* str5 = "msg5";
   const char* str6 = "msg6";
 
   // Add two messages.
   Message* msg1 = new Message(
       port, AllocMsg(str1), strlen(str1) + 1, Message::kNormalPriority);
   queue.Enqueue(msg1, false);
+  EXPECT(queue.Length() == 1);
   EXPECT(!queue.IsEmpty());
+  it.Reset(&queue);
+  EXPECT(it.HasNext());
+  EXPECT(it.Next() == msg1);
+  EXPECT(!it.HasNext());
 
   Message* msg2 = new Message(
       port, AllocMsg(str2), strlen(str2) + 1, Message::kNormalPriority);
   queue.Enqueue(msg2, false);
+  EXPECT(queue.Length() == 2);
   EXPECT(!queue.IsEmpty());
+  it.Reset(&queue);
+  EXPECT(it.HasNext());
+  EXPECT(it.Next() == msg1);
+  EXPECT(it.HasNext());
+  EXPECT(it.Next() == msg2);
+  EXPECT(!it.HasNext());
 
-  // Remove two messages.
+  // Lookup messages by id.
+  EXPECT(queue.FindMessageById(reinterpret_cast<intptr_t>(msg1)) == msg1);
+  EXPECT(queue.FindMessageById(reinterpret_cast<intptr_t>(msg2)) == msg2);
+
+  // Lookup bad id.
+  EXPECT(queue.FindMessageById(0x1) == NULL);
+
+  // Remove message 1
   Message* msg = queue.Dequeue();
   EXPECT(msg != NULL);
   EXPECT_STREQ(str1, reinterpret_cast<char*>(msg->data()));
   EXPECT(!queue.IsEmpty());
 
+  it.Reset(&queue);
+  EXPECT(it.HasNext());
+  EXPECT(it.Next() == msg2);
+
+  // Remove message 2
   msg = queue.Dequeue();
   EXPECT(msg != NULL);
   EXPECT_STREQ(str2, reinterpret_cast<char*>(msg->data()));
   EXPECT(queue.IsEmpty());
 
   Message* msg3 = new Message(Message::kIllegalPort,
                               AllocMsg(str3), strlen(str3) + 1,
                               Message::kNormalPriority);
   queue.Enqueue(msg3, true);
   EXPECT(!queue.IsEmpty());
@@ skipping 63 matching lines @@
   queue.Enqueue(msg2, false);
 
   EXPECT(!queue.IsEmpty());
   queue.Clear();
   EXPECT(queue.IsEmpty());
 
   // msg1 and msg2 already delete by FlushAll.
 }
 
 }  // namespace dart