Move ScopedClosureRunner to callback_helpers, add Reset.

BUG=none
TEST=none
TBR=ben@chromium.org

Review URL: https://chromiumcodereview.appspot.com/23514018

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@220473 0039d316-1c4b-4281-b951-d872f2087c98

10 files changed, 92 insertions, 40 deletions

diff --git a/base/base.gyp b/base/base.gyp
index fabc868..0cdcaa4 100644
--- a/base/base.gyp
+++ b/base/base.gyp
@@ -455,11 +455,11 @@
         'atomicops_unittest.cc',
         'barrier_closure_unittest.cc',
         'base64_unittest.cc',
-        'bind_helpers_unittest.cc',
         'bind_unittest.cc',
         'bind_unittest.nc',
         'bits_unittest.cc',
         'build_time_unittest.cc',
+        'callback_helpers_unittest.cc',
         'callback_unittest.cc',
         'callback_unittest.nc',
         'cancelable_callback_unittest.cc',
diff --git a/base/base.gypi b/base/base.gypi
index 02697b2..9bac4fd 100644
--- a/base/base.gypi
+++ b/base/base.gypi
@@ -104,6 +104,7 @@
           'build_time.cc',
           'build_time.h',
           'callback.h',
+          'callback_helpers.cc',
           'callback_helpers.h',
           'callback_internal.cc',
           'callback_internal.h',
diff --git a/base/bind_helpers.cc b/base/bind_helpers.cc
index f2fc3bb..f1fe46d 100644
--- a/base/bind_helpers.cc
+++ b/base/bind_helpers.cc
@@ -11,19 +11,4 @@ namespace base {
 void DoNothing() {
 }
 
-ScopedClosureRunner::ScopedClosureRunner(const Closure& closure)
-    : closure_(closure) {
-}
-
-ScopedClosureRunner::~ScopedClosureRunner() {
-  if (!closure_.is_null())
-    closure_.Run();
-}
-
-Closure ScopedClosureRunner::Release() {
-  Closure result = closure_;
-  closure_.Reset();
-  return result;
-}
-
 }  // namespace base
diff --git a/base/bind_helpers.h b/base/bind_helpers.h
index 0cfaab7..d717892 100644
--- a/base/bind_helpers.h
+++ b/base/bind_helpers.h
@@ -139,10 +139,6 @@
 //                        pointer when invoked. Only use this when necessary.
 //                        In most cases MessageLoop::DeleteSoon() is a better
 //                        fit.
-//   ScopedClosureRunner - Scoper object that runs the wrapped closure when it
-//                         goes out of scope. It's conceptually similar to
-//                         scoped_ptr<> but calls Run() instead of deleting
-//                         the pointer.
 
 #ifndef BASE_BIND_HELPERS_H_
 #define BASE_BIND_HELPERS_H_
@@ -543,21 +539,6 @@ void DeletePointer(T* obj) {
   delete obj;
 }
 
-// ScopedClosureRunner is akin to scoped_ptr for Closures. It ensures that the
-// Closure is executed and deleted no matter how the current scope exits.
-class BASE_EXPORT ScopedClosureRunner {
- public:
-  explicit ScopedClosureRunner(const Closure& closure);
-  ~ScopedClosureRunner();
-
-  Closure Release();
-
- private:
-  Closure closure_;
-
-  DISALLOW_IMPLICIT_CONSTRUCTORS(ScopedClosureRunner);
-};
-
 }  // namespace base
 
 #endif  // BASE_BIND_HELPERS_H_
diff --git a/base/callback_helpers.cc b/base/callback_helpers.cc
new file mode 100644
index 0000000..ef02b2b
--- /dev/null
+++ b/base/callback_helpers.cc
@@ -0,0 +1,42 @@
+// Copyright 2013 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/callback_helpers.h"
+
+#include "base/callback.h"
+
+namespace base {
+
+ScopedClosureRunner::ScopedClosureRunner() {
+}
+
+ScopedClosureRunner::ScopedClosureRunner(const Closure& closure)
+    : closure_(closure) {
+}
+
+ScopedClosureRunner::~ScopedClosureRunner() {
+  if (!closure_.is_null())
+    closure_.Run();
+}
+
+void ScopedClosureRunner::Reset() {
+  Closure old_closure = Release();
+  if (!old_closure.is_null())
+    old_closure.Run();
+}
+
+void ScopedClosureRunner::Reset(const Closure& closure) {
+  Closure old_closure = Release();
+  closure_ = closure;
+  if (!old_closure.is_null())
+    old_closure.Run();
+}
+
+Closure ScopedClosureRunner::Release() {
+  Closure result = closure_;
+  closure_.Reset();
+  return result;
+}
+
+}  // namespace base
diff --git a/base/callback_helpers.h b/base/callback_helpers.h
index 52cb71b..8481e3e 100644
--- a/base/callback_helpers.h
+++ b/base/callback_helpers.h
@@ -14,7 +14,9 @@
 #ifndef BASE_CALLBACK_HELPERS_H_
 #define BASE_CALLBACK_HELPERS_H_
 
+#include "base/basictypes.h"
 #include "base/callback.h"
+#include "base/compiler_specific.h"
 
 namespace base {
 
@@ -25,6 +27,24 @@ base::Callback<Sig> ResetAndReturn(base::Callback<Sig>* cb) {
   return ret;
 }
 
+// ScopedClosureRunner is akin to scoped_ptr for Closures. It ensures that the
+// Closure is executed and deleted no matter how the current scope exits.
+class BASE_EXPORT ScopedClosureRunner {
+ public:
+  ScopedClosureRunner();
+  explicit ScopedClosureRunner(const Closure& closure);
+  ~ScopedClosureRunner();
+
+  void Reset();
+  void Reset(const Closure& closure);
+  Closure Release() WARN_UNUSED_RESULT;
+
+ private:
+  Closure closure_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedClosureRunner);
+};
+
 }  // namespace base
 
 #endif  // BASE_CALLBACK_HELPERS_H_
diff --git a/base/bind_helpers_unittest.cc b/base/callback_helpers_unittest.cc
index 3ef2d75..3b17a6b 100644
--- a/base/bind_helpers_unittest.cc
+++ b/base/callback_helpers_unittest.cc
@@ -1,11 +1,11 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2013 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/bind_helpers.h"
+#include "base/callback_helpers.h"
 
-#include "base/callback.h"
 #include "base/bind.h"
+#include "base/callback.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
@@ -36,4 +36,26 @@ TEST(BindHelpersTest, TestScopedClosureRunnerRelease) {
   EXPECT_EQ(1, run_count);
 }
 
+TEST(BindHelpersTest, TestScopedClosureRunnerReset) {
+  int run_count_1 = 0;
+  int run_count_2 = 0;
+  {
+    base::ScopedClosureRunner runner;
+    runner.Reset(base::Bind(&Increment, &run_count_1));
+    runner.Reset(base::Bind(&Increment, &run_count_2));
+    EXPECT_EQ(1, run_count_1);
+    EXPECT_EQ(0, run_count_2);
+  }
+  EXPECT_EQ(1, run_count_2);
+
+  int run_count_3 = 0;
+  {
+    base::ScopedClosureRunner runner(base::Bind(&Increment, &run_count_3));
+    EXPECT_EQ(0, run_count_3);
+    runner.Reset();
+    EXPECT_EQ(1, run_count_3);
+  }
+  EXPECT_EQ(1, run_count_3);
+}
+
 }  // namespace
diff --git a/base/mac/bind_objc_block_unittest.mm b/base/mac/bind_objc_block_unittest.mm
index 888b3dc..a4bcd76 100644
--- a/base/mac/bind_objc_block_unittest.mm
+++ b/base/mac/bind_objc_block_unittest.mm
@@ -6,7 +6,7 @@
 
 #include "base/callback.h"
 #include "base/bind.h"
-#include "base/bind_helpers.h"
+#include "base/callback_helpers.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
diff --git a/base/prefs/pref_member.cc b/base/prefs/pref_member.cc
index e3f6ac0..eb70839 100644
--- a/base/prefs/pref_member.cc
+++ b/base/prefs/pref_member.cc
@@ -4,8 +4,8 @@
 
 #include "base/prefs/pref_member.h"
 
-#include "base/bind_helpers.h"
 #include "base/callback.h"
+#include "base/callback_helpers.h"
 #include "base/location.h"
 #include "base/prefs/pref_service.h"
 #include "base/value_conversions.h"
diff --git a/base/test/unit_test_launcher.cc b/base/test/unit_test_launcher.cc
index 49ad727..0116bba 100644
--- a/base/test/unit_test_launcher.cc
+++ b/base/test/unit_test_launcher.cc
@@ -5,6 +5,7 @@
 #include "base/test/unit_test_launcher.h"
 
 #include "base/bind.h"
+#include "base/callback_helpers.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/files/scoped_temp_dir.h"