mojo: Support sync calls through ThreadSafeInterfacePtr

mojo/public/cpp/bindings/tests/interface_ptr_unittest.cc

Index: mojo/public/cpp/bindings/tests/interface_ptr_unittest.cc
diff --git a/mojo/public/cpp/bindings/tests/interface_ptr_unittest.cc b/mojo/public/cpp/bindings/tests/interface_ptr_unittest.cc
index 431a84425076dbd97dfb612a3501ee41b937e11e..39a63581daec5346f86b248c7ef17725e1d06842 100644
--- a/mojo/public/cpp/bindings/tests/interface_ptr_unittest.cc
+++ b/mojo/public/cpp/bindings/tests/interface_ptr_unittest.cc
@@ -19,6 +19,7 @@
 #include "mojo/public/interfaces/bindings/tests/sample_interfaces.mojom.h"
 #include "mojo/public/interfaces/bindings/tests/sample_service.mojom.h"
 #include "mojo/public/interfaces/bindings/tests/scoping.mojom.h"
+#include "mojo/public/interfaces/bindings/tests/test_sync_methods.mojom.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace mojo {
@@ -932,6 +933,80 @@ TEST_F(InterfacePtrTest, ThreadSafeInterfacePointerWithTaskRunner) {
   thread_safe_ptr = nullptr;
 }
 
+class TestSyncImpl : public TestSync {
+ public:
+  explicit TestSyncImpl(TestSyncRequest request)
+      : binding_(this, std::move(request)) {}
+
+  // TestSync implementation:
+  void Ping(const PingCallback& callback) override { callback.Run(); }
+  void Echo(int32_t value, const EchoCallback& callback) override {
+    callback.Run(value);
+  }
+  void AsyncEcho(int32_t value, const AsyncEchoCallback& callback) override {
+    callback.Run(value);
+  }
+
+  Binding<TestSync>* binding() { return &binding_; }
+
+ private:
+  Binding<TestSync> binding_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestSyncImpl);
+};
+
+TEST_F(InterfacePtrTest, ThreadSafeSyncCall) {
+  // Create and start the thread from where we'll bind the interface pointer.
+  base::Thread other_thread("service test thread");
+  other_thread.Start();
+  const scoped_refptr<base::SingleThreadTaskRunner>& other_thread_task_runner =
+      other_thread.message_loop()->task_runner();
+
+  TestSyncPtr ptr;
+  TestSyncRequest request(&ptr);
+
+  // Create a ThreadSafeInterfacePtr that we'll bind from a different thread.
+  scoped_refptr<ThreadSafeTestSyncPtr> thread_safe_ptr =
+      ThreadSafeTestSyncPtr::Create(ptr.PassInterface(),
+                                    other_thread_task_runner);
+  ASSERT_TRUE(thread_safe_ptr);
+
+  TestSyncImpl* test_sync_impl = nullptr;
+  {
+    base::RunLoop run_loop;
+    auto create_impl = base::Bind(
+        [](TestSyncRequest request, TestSyncImpl** test_sync_impl) {
+          // In real life, the implementation would have a legitimate owner.
+          *test_sync_impl = new TestSyncImpl(std::move(request));
+        },
+        base::Passed(&request), &test_sync_impl);
+    other_thread_task_runner->PostTaskAndReply(FROM_HERE, create_impl,
+                                               run_loop.QuitClosure());
+    run_loop.Run();
+  }
+
+  int32_t output = -1;
+  (*thread_safe_ptr)->Echo(123, &output);
+  ASSERT_EQ(123, output);
+
+  other_thread_task_runner->DeleteSoon(FROM_HERE, test_sync_impl);
+
+  // Reset the pointer now so the InterfacePtr associated resources can be
+  // deleted before the background thread's message loop is invalidated.
+  thread_safe_ptr = nullptr;
+}
+
+TEST_F(InterfacePtrTest, ThreadSafeSyncCallSameThread) {
+  TestSyncPtr ptr;
+  auto impl = base::MakeUnique<TestSyncImpl>(MakeRequest(&ptr));
+  scoped_refptr<ThreadSafeTestSyncPtr> thread_safe_ptr =
+      ThreadSafeTestSyncPtr::Create(std::move(ptr));
+
+  int32_t output = -1;
+  (*thread_safe_ptr)->Echo(123, &output);
+  ASSERT_EQ(123, output);
+}
+
 }  // namespace
 }  // namespace test
 }  // namespace mojo