Add IPC serialization support for base::Optional

ipc/ipc_message_utils_unittest.cc

 // Copyright (c) 2012 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 "ipc/ipc_message_utils.h"
 
 #include <stddef.h>
 #include <stdint.h>
 #include <memory>
 
@@ skipping 140 matching lines @@
   EXPECT_TRUE(IPC::ReadParam(&message, &iter, &result_handle));
   EXPECT_TRUE(result_handle.name.empty());
 #if defined(OS_POSIX)
   EXPECT_EQ(-1, result_handle.socket.fd);
 #elif defined(OS_WIN)
   EXPECT_EQ(nullptr, result_handle.pipe.handle);
 #endif
   EXPECT_EQ(channel_handle.mojo_handle, result_handle.mojo_handle);
 }
 
+TEST(IPCMessageUtilsTest, OptionalUnset) {
+  base::Optional<int> opt;
+  base::Pickle pickle;
+  IPC::WriteParam(&pickle, opt);
+
+  base::PickleSizer sizer;
+  IPC::GetParamSize(&sizer, opt);
+
+  EXPECT_EQ(sizer.payload_size(), pickle.payload_size());
+
+  std::string log;
+  IPC::LogParam(opt, &log);
+  EXPECT_EQ("(unset)", log);
+
+  base::Optional<int> unserialized_opt;
+  base::PickleIterator iter(pickle);
+  EXPECT_TRUE(IPC::ReadParam(&pickle, &iter, &unserialized_opt));
+  EXPECT_FALSE(unserialized_opt);
+}
+
+TEST(IPCMessageUtilsTest, OptionalSet) {
+  base::Optional<int> opt(10);
+  base::Pickle pickle;
+  IPC::WriteParam(&pickle, opt);
+
+  base::PickleSizer sizer;
+  IPC::GetParamSize(&sizer, opt);
+
+  EXPECT_EQ(sizer.payload_size(), pickle.payload_size());
+
+  std::string log;
+  IPC::LogParam(opt, &log);
+  EXPECT_EQ("10", log);
+
+  base::Optional<int> unserialized_opt;
+  base::PickleIterator iter(pickle);
+  EXPECT_TRUE(IPC::ReadParam(&pickle, &iter, &unserialized_opt));
+  EXPECT_TRUE(unserialized_opt);
+  EXPECT_EQ(opt.value(), unserialized_opt.value());
+}
+
 }  // namespace
 }  // namespace IPC