Fix mapping of JS objects/arrays to C++

[ChangeLog][QtQml][Important Behavior Changes] When a JavaScript object/array
is passed to C++ through a QVariant, the engine no longer immediately converts
the object recursively into a QVariantMap or QVariantList but instead stores
a QJSValue in the QVariant. This prevents a loss of data when the JS object
contains non-primitive types such as function objects for example. Code that
expects the variant type to be exactly QVariant::Map or QVariant::List may
need to be adapted. Registered conversion functions however ensure that code
that merely calls toMap() or toList() continues to work.

Task-number: QTBUG-40431
Change-Id: I1dbc1d5f8e78ad28bb62db3681b9a0b34557e7f5
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

1 files changed, 5 insertions, 15 deletions

diff --git a/src/qml/qml/v8/qv8engine_p.h b/src/qml/qml/v8/qv8engine_p.h
index e2c96ffc87..51e857c8a2 100644
--- a/src/qml/qml/v8/qv8engine_p.h
+++ b/src/qml/qml/v8/qv8engine_p.h
@@ -197,9 +197,13 @@ public:
 
     void freezeObject(const QV4::ValueRef value);
 
-    QVariant toVariant(const QV4::ValueRef value, int typeHint);
+    QVariant toVariant(const QV4::ValueRef value, int typeHint, bool createJSValueForObjects = true, V8ObjectSet *visitedObjects = 0);
+    QVariant objectToVariant(QV4::Object *o, V8ObjectSet *visitedObjects = 0);
     QV4::ReturnedValue fromVariant(const QVariant &);
 
+    QVariantMap variantMapFromJS(QV4::Object *o)
+    { return objectToVariant(o).toMap(); }
+
     // Return a JS string for the given QString \a string
     QV4::ReturnedValue toString(const QString &string);
 
@@ -218,16 +222,8 @@ public:
     void setExtensionData(int, Deletable *);
 
     QV4::ReturnedValue variantListToJS(const QVariantList &lst);
-    inline QVariantList variantListFromJS(QV4::ArrayObject *array)
-    { V8ObjectSet visitedObjects; return variantListFromJS(array, visitedObjects); }
-
     QV4::ReturnedValue variantMapToJS(const QVariantMap &vmap);
-    inline QVariantMap variantMapFromJS(QV4::Object *object)
-    { V8ObjectSet visitedObjects; return variantMapFromJS(object, visitedObjects); }
-
     QV4::ReturnedValue variantToJS(const QVariant &value);
-    inline QVariant variantFromJS(const QV4::ValueRef value)
-    { V8ObjectSet visitedObjects; return variantFromJS(value, visitedObjects); }
 
     QV4::ReturnedValue metaTypeToJS(int type, const void *data);
     bool metaTypeFromJS(const QV4::ValueRef value, int type, void *data);
@@ -265,15 +261,9 @@ protected:
 
     QHash<QString, quint32> m_consoleCount;
 
-    QVariant toBasicVariant(const QV4::ValueRef);
-
     void initializeGlobal();
 
 private:
-    QVariantList variantListFromJS(QV4::ArrayObject *array, V8ObjectSet &visitedObjects);
-    QVariantMap variantMapFromJS(QV4::Object *object, V8ObjectSet &visitedObjects);
-    QVariant variantFromJS(const QV4::ValueRef value, V8ObjectSet &visitedObjects);
-
     Q_DISABLE_COPY(QV8Engine)
 };