Add a CallbackWithReturnValue as a convenient method of calling callback functions with no arguments and a return value. This is useful in calling all of the getters we have in the code, instead of creating wrapper functions that take a pointer argument.

Review URL: http://codereview.chromium.org/155630

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@20975 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 40 insertions, 0 deletions

diff --git a/base/task_unittest.cc b/base/task_unittest.cc
new file mode 100644
index 0000000..1fa7c9d
--- /dev/null
+++ b/base/task_unittest.cc
@@ -0,0 +1,40 @@
+// Copyright (c) 2009 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 "base/scoped_ptr.h"
+#include "base/task.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace {
+
+class HelperObject {
+ public:
+  HelperObject() : next_number_(0) { }
+  int GetNextNumber() { return ++next_number_; }
+  void GetNextNumberArg(int* number) { *number = GetNextNumber(); }
+
+ private:
+  int next_number_;
+};
+
+}  // namespace
+
+TEST(Task, OneArg) {
+  HelperObject obj;
+  scoped_ptr<Callback1<int*>::Type> callback(
+      NewCallback(&obj, &HelperObject::GetNextNumberArg));
+
+  int number = 0;
+  callback->Run(&number);
+  EXPECT_EQ(number, 1);
+}
+
+TEST(Task, ReturnValue) {
+  HelperObject obj;
+  scoped_ptr<CallbackWithReturnValue<int>::Type> callback(
+      NewCallbackWithReturnValue(&obj, &HelperObject::GetNextNumber));
+
+  EXPECT_EQ(callback->Run(), 1);
+}