From 11f664083ad98eed2ed1af768093aa0560d474b2 Mon Sep 17 00:00:00 2001
From: John Maguire <john.maguire@gmail.com>
Date: Mon, 26 Nov 2012 09:41:26 +0100
Subject: [PATCH] Add support for standard function callbacks in NewClosure
 (including C++11 lambdas).

---
 ext/libclementine-common/core/closure.cpp | 20 ++++++++++++++++++++
 ext/libclementine-common/core/closure.h   | 18 ++++++++++++++++++
 tests/closure_test.cpp                    | 11 +++++++++++
 3 files changed, 49 insertions(+)

diff --git a/ext/libclementine-common/core/closure.cpp b/ext/libclementine-common/core/closure.cpp
index eccc81ea7..e2c27c13f 100644
--- a/ext/libclementine-common/core/closure.cpp
+++ b/ext/libclementine-common/core/closure.cpp
@@ -30,6 +30,18 @@ ClosureBase::ClosureBase(ObjectHelper* helper)
 ClosureBase::~ClosureBase() {
 }
 
+CallbackClosure::CallbackClosure(
+    QObject* sender,
+    const char* signal,
+    std::function<void()> callback)
+  : ClosureBase(new ObjectHelper(sender, signal, this)),
+    callback_(callback) {
+}
+
+void CallbackClosure::Invoke() {
+  callback_();
+}
+
 ObjectHelper* ClosureBase::helper() const {
   return helper_;
 }
@@ -52,6 +64,14 @@ void Unpack(QList<QGenericArgument>*) {}
 
 }  // namespace _detail
 
+_detail::ClosureBase* NewClosure(
+    QObject* sender,
+    const char* signal,
+    std::function<void()> callback) {
+  return new _detail::CallbackClosure(
+      sender, signal, callback);
+}
+
 void DoAfter(QObject* receiver, const char* slot, int msec) {
   QTimer::singleShot(msec, receiver, slot);
 }
diff --git a/ext/libclementine-common/core/closure.h b/ext/libclementine-common/core/closure.h
index 59d05a7be..ca85ce91d 100644
--- a/ext/libclementine-common/core/closure.h
+++ b/ext/libclementine-common/core/closure.h
@@ -150,6 +150,19 @@ class SharedClosure : public Closure<Args...> {
   QSharedPointer<T> data_;
 };
 
+class CallbackClosure : public ClosureBase {
+ public:
+  CallbackClosure(
+      QObject* sender,
+      const char* signal,
+      std::function<void()> callback);
+
+  virtual void Invoke();
+
+ private:
+  std::function<void()> callback_;
+};
+
 }  // namespace _detail
 
 template <typename... Args>
@@ -175,6 +188,11 @@ _detail::ClosureBase* NewClosure(
       sender, signal, receiver, slot, args...);
 }
 
+_detail::ClosureBase* NewClosure(
+    QObject* sender,
+    const char* signal,
+    std::function<void()> callback);
+
 
 void DoAfter(QObject* receiver, const char* slot, int msec);
 void DoInAMinuteOrSo(QObject* receiver, const char* slot);
diff --git a/tests/closure_test.cpp b/tests/closure_test.cpp
index 8d26ccfad..486a6d75b 100644
--- a/tests/closure_test.cpp
+++ b/tests/closure_test.cpp
@@ -62,3 +62,14 @@ TEST(ClosureTest, ClosureDoesNotCrashWithSharedPointerSender) {
   ASSERT_EQ(1, spy->count());
   EXPECT_TRUE(closure.isNull());
 }
+
+TEST(ClosureTest, ClosureCallsLambda) {
+  TestQObject sender;
+  bool called = false;
+  _detail::ClosureBase* closure = NewClosure(
+      &sender, SIGNAL(Emitted()),
+      [&called] () { called = true; });
+  EXPECT_FALSE(called);
+  sender.Emit();
+  EXPECT_TRUE(called);
+}