Add C++11 move operators, and a simpler internal constructor

Move semantics should optimize some copy operations on QJSValues,
and the internal constructor will simplify refactoring the
QJSValue class to get rid of the extra allocated private.

Change-Id: I24863b30523af2432aa81ad6b87fda7fe35749c4
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

4 files changed, 31 insertions, 18 deletions

diff --git a/src/qml/jsapi/qjsengine.cpp b/src/qml/jsapi/qjsengine.cpp
index d54af28f26..e82849746f 100644
--- a/src/qml/jsapi/qjsengine.cpp
+++ b/src/qml/jsapi/qjsengine.cpp
@@ -317,7 +317,7 @@ QJSValue QJSEngine::evaluate(const QString& program, const QString& fileName, in
         result = v4->catchException();
     if (ctx->d() != v4->rootContext())
         v4->popContext();
-    return new QJSValuePrivate(v4, result);
+    return QJSValue(v4, result.asReturnedValue());
 }
 
 /*!
@@ -332,7 +332,7 @@ QJSValue QJSEngine::newObject()
 {
     QV4::Scope scope(d->m_v4Engine);
     QV4::ScopedValue v(scope, d->m_v4Engine->newObject());
-    return new QJSValuePrivate(d->m_v4Engine, v);
+    return QJSValue(d->m_v4Engine, v.asReturnedValue());
 }
 
 /*!
@@ -347,7 +347,7 @@ QJSValue QJSEngine::newArray(uint length)
     if (length < 0x1000)
         array->arrayReserve(length);
     array->setArrayLengthUnchecked(length);
-    return new QJSValuePrivate(d->m_v4Engine, array);
+    return QJSValue(d->m_v4Engine, array.asReturnedValue());
 }
 
 /*!
@@ -381,7 +381,7 @@ QJSValue QJSEngine::newQObject(QObject *object)
             QQmlEngine::setObjectOwnership(object, QQmlEngine::JavaScriptOwnership);
     }
     QV4::ScopedValue v(scope, QV4::QObjectWrapper::wrap(v4, object));
-    return new QJSValuePrivate(v4, v);
+    return QJSValue(v4, v.asReturnedValue());
 }
 
 /*!
@@ -399,7 +399,7 @@ QJSValue QJSEngine::globalObject() const
     Q_D(const QJSEngine);
     QV4::Scope scope(d->m_v4Engine);
     QV4::ScopedValue v(scope, d->m_v4Engine->globalObject());
-    return new QJSValuePrivate(d->m_v4Engine, v);
+    return QJSValue(d->m_v4Engine, v.asReturnedValue());
 }
 
 /*!
@@ -411,7 +411,7 @@ QJSValue QJSEngine::create(int type, const void *ptr)
     Q_D(QJSEngine);
     QV4::Scope scope(d->m_v4Engine);
     QV4::ScopedValue v(scope, scope.engine->metaTypeToJS(type, ptr));
-    return new QJSValuePrivate(d->m_v4Engine, v);
+    return QJSValue(d->m_v4Engine, v.asReturnedValue());
 }
 
 /*!
diff --git a/src/qml/jsapi/qjsvalue.cpp b/src/qml/jsapi/qjsvalue.cpp
index 0a29e7802c..479a2d0901 100644
--- a/src/qml/jsapi/qjsvalue.cpp
+++ b/src/qml/jsapi/qjsvalue.cpp
@@ -172,8 +172,11 @@ QJSValue::QJSValue(bool value)
 {
 }
 
-QJSValue::QJSValue(QJSValuePrivate *dd)
-    : d(dd)
+/*!
+  \internal
+*/
+QJSValue::QJSValue(ExecutionEngine *e, quint64 val)
+    : d(new QJSValuePrivate(e, val))
 {
 }
 
@@ -255,7 +258,8 @@ QJSValue::QJSValue(const QJSValue& other)
 */
 QJSValue::~QJSValue()
 {
-    d->deref();
+    if (d)
+        d->deref();
 }
 
 /*!
@@ -642,7 +646,7 @@ QJSValue QJSValue::call(const QJSValueList &args)
     if (engine->hasException)
         result = engine->catchException();
 
-    return new QJSValuePrivate(engine, result);
+    return QJSValue(engine, result.asReturnedValue());
 }
 
 /*!
@@ -697,7 +701,7 @@ QJSValue QJSValue::callWithInstance(const QJSValue &instance, const QJSValueList
     if (engine->hasException)
         result = engine->catchException();
 
-    return new QJSValuePrivate(engine, result);
+    return QJSValue(engine, result.asReturnedValue());
 }
 
 /*!
@@ -744,7 +748,7 @@ QJSValue QJSValue::callAsConstructor(const QJSValueList &args)
     if (engine->hasException)
         result = engine->catchException();
 
-    return new QJSValuePrivate(engine, result);
+    return QJSValue(engine, result.asReturnedValue());
 }
 
 #ifdef QT_DEPRECATED
@@ -785,7 +789,7 @@ QJSValue QJSValue::prototype() const
     ScopedObject p(scope, o->prototype());
     if (!p)
         return QJSValue(NullValue);
-    return new QJSValuePrivate(o->internalClass()->engine, p);
+    return QJSValue(o->internalClass()->engine, p.asReturnedValue());
 }
 
 /*!
@@ -979,7 +983,7 @@ QJSValue QJSValue::property(const QString& name) const
     if (engine->hasException)
         result = engine->catchException();
 
-    return new QJSValuePrivate(engine, result);
+    return QJSValue(engine, result.asReturnedValue());
 }
 
 /*!
@@ -1008,7 +1012,7 @@ QJSValue QJSValue::property(quint32 arrayIndex) const
     QV4::ScopedValue result(scope, arrayIndex == UINT_MAX ? o->get(engine->id_uintMax) : o->getIndexed(arrayIndex));
     if (engine->hasException)
         engine->catchException();
-    return new QJSValuePrivate(engine, result);
+    return QJSValue(engine, result.asReturnedValue());
 }
 
 /*!
diff --git a/src/qml/jsapi/qjsvalue.h b/src/qml/jsapi/qjsvalue.h
index d184cf6537..4ff86b1edc 100644
--- a/src/qml/jsapi/qjsvalue.h
+++ b/src/qml/jsapi/qjsvalue.h
@@ -41,7 +41,6 @@
 
 QT_BEGIN_NAMESPACE
 
-
 class QJSValue;
 class QJSEngine;
 class QVariant;
@@ -51,6 +50,10 @@ class QDateTime;
 
 typedef QList<QJSValue> QJSValueList;
 class QJSValuePrivate;
+namespace QV4 {
+    struct ExecutionEngine;
+    struct Value;
+}
 
 class Q_QML_EXPORT QJSValue
 {
@@ -65,6 +68,12 @@ public:
     ~QJSValue();
     QJSValue(const QJSValue &other);
 
+#ifdef Q_COMPILER_RVALUE_REFS
+    inline QJSValue(QJSValue && other) : d(other.d) { other.d = 0; }
+    inline QJSValue &operator=(QJSValue &&other)
+    { qSwap(d, other.d); return *this; }
+#endif
+
     QJSValue(bool value);
     QJSValue(int value);
     QJSValue(uint value);
@@ -125,7 +134,7 @@ public:
     QT_DEPRECATED QJSEngine *engine() const;
 #endif
 
-    QJSValue(QJSValuePrivate *dd);
+    QJSValue(QV4::ExecutionEngine *e, quint64 val);
 private:
     friend class QJSValuePrivate;
     // force compile error, prevent QJSValue(bool) to be called
diff --git a/src/qml/jsapi/qjsvalueiterator.cpp b/src/qml/jsapi/qjsvalueiterator.cpp
index e23bd5d763..2b27f655c8 100644
--- a/src/qml/jsapi/qjsvalueiterator.cpp
+++ b/src/qml/jsapi/qjsvalueiterator.cpp
@@ -201,7 +201,7 @@ QJSValue QJSValueIterator::value() const
         engine->catchException();
         return QJSValue();
     }
-    return new QJSValuePrivate(engine, v);
+    return QJSValue(engine, v.asReturnedValue());
 }