Make removal of bindings explicit

This simplifies the code for further refactoring.

Change-Id: I6bcb5ce397f642242af80ce37dc8bba1fa9bf3f5
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>

4 files changed, 34 insertions, 23 deletions

diff --git a/src/qml/qml/qqmlobjectcreator.cpp b/src/qml/qml/qqmlobjectcreator.cpp
index ba18967150..a1787f67fd 100644
--- a/src/qml/qml/qqmlobjectcreator.cpp
+++ b/src/qml/qml/qqmlobjectcreator.cpp
@@ -66,7 +66,7 @@ static void removeBindingOnProperty(QObject *o, int index)
 {
     int coreIndex;
     int valueTypeIndex = QQmlPropertyData::decodeValueTypePropertyIndex(index, &coreIndex);
-    QQmlAbstractBinding *binding = QQmlPropertyPrivate::setBinding(o, coreIndex, valueTypeIndex, 0);
+    QQmlAbstractBinding *binding = QQmlPropertyPrivate::removeBinding(o, coreIndex, valueTypeIndex);
     if (binding) binding->destroy();
 }
 
@@ -664,7 +664,7 @@ void QQmlObjectCreator::setupBindings(const QBitArray &bindingsToSkip)
             QQmlPropertyPrivate::binding(_bindingTarget, _valueTypeProperty->coreIndex, -1);
 
         if (binding && binding->bindingType() != QQmlAbstractBinding::ValueTypeProxy) {
-            QQmlPropertyPrivate::setBinding(_bindingTarget, _valueTypeProperty->coreIndex, -1, 0);
+            QQmlPropertyPrivate::removeBinding(_bindingTarget, _valueTypeProperty->coreIndex, -1);
             binding->destroy();
         } else if (binding) {
             QQmlValueTypeProxyBinding *proxy =
diff --git a/src/qml/qml/qqmlproperty.cpp b/src/qml/qml/qqmlproperty.cpp
index 55f4def6a8..3ab312036b 100644
--- a/src/qml/qml/qqmlproperty.cpp
+++ b/src/qml/qml/qqmlproperty.cpp
@@ -719,30 +719,35 @@ QQmlPropertyPrivate::binding(const QQmlProperty &that)
 */
 QQmlAbstractBinding *
 QQmlPropertyPrivate::setBinding(const QQmlProperty &that,
-                                        QQmlAbstractBinding *newBinding,
-                                        WriteFlags flags)
+                                QQmlAbstractBinding *newBinding,
+                                WriteFlags flags)
 {
+    if (!newBinding)
+        removeBinding(that);
+
     if (!that.d || !that.isProperty() || !that.d->object) {
-        if (newBinding)
-            newBinding->destroy();
+        newBinding->destroy();
         return 0;
     }
 
-    if (newBinding) {
-        // In the case that the new binding is provided, we must target the property it
-        // is associated with.  If we don't do this, retargetBinding() can fail.
-        QObject *object = newBinding->object();
-        int pi = newBinding->propertyIndex();
+    // In the case that the new binding is provided, we must target the property it
+    // is associated with.  If we don't do this, retargetBinding() can fail.
+    QObject *object = newBinding->object();
+    int pi = newBinding->propertyIndex();
 
-        int core;
-        int vt = QQmlPropertyData::decodeValueTypePropertyIndex(pi, &core);
+    int core;
+    int vt = QQmlPropertyData::decodeValueTypePropertyIndex(pi, &core);
 
-        return setBinding(object, core, vt, newBinding, flags);
-    } else {
-        return setBinding(that.d->object, that.d->core.coreIndex,
-                          that.d->core.getValueTypeCoreIndex(),
-                          newBinding, flags);
-    }
+    return setBinding(object, core, vt, newBinding, flags);
+}
+
+QQmlAbstractBinding *QQmlPropertyPrivate::removeBinding(const QQmlProperty &that)
+{
+    if (!that.d || !that.isProperty() || !that.d->object)
+        return 0;
+
+    return removeBinding(that.d->object, that.d->core.coreIndex,
+                         that.d->core.getValueTypeCoreIndex());
 }
 
 QQmlAbstractBinding *
@@ -877,6 +882,11 @@ QQmlPropertyPrivate::setBinding(QObject *object, int coreIndex, int valueTypeInd
     return binding;
 }
 
+QQmlAbstractBinding *QQmlPropertyPrivate::removeBinding(QObject *object, int coreIndex, int valueTypeIndex)
+{
+    return setBinding(object, coreIndex, valueTypeIndex, 0);
+}
+
 QQmlAbstractBinding *
 QQmlPropertyPrivate::setBindingNoEnable(QObject *object, int coreIndex, int valueTypeIndex,
                                                 QQmlAbstractBinding *newBinding)
@@ -1212,9 +1222,8 @@ QQmlPropertyPrivate::writeValueProperty(QObject *object,
 {
     // Remove any existing bindings on this property
     if (!(flags & DontRemoveBinding) && object) {
-        QQmlAbstractBinding *binding = setBinding(object, core.coreIndex,
-                                                          core.getValueTypeCoreIndex(),
-                                                          0, flags);
+        QQmlAbstractBinding *binding = removeBinding(object, core.coreIndex,
+                                                          core.getValueTypeCoreIndex());
         if (binding) binding->destroy();
     }
 
diff --git a/src/qml/qml/qqmlproperty_p.h b/src/qml/qml/qqmlproperty_p.h
index ece168925b..4b51128fef 100644
--- a/src/qml/qml/qqmlproperty_p.h
+++ b/src/qml/qml/qqmlproperty_p.h
@@ -108,6 +108,7 @@ public:
                                                    int valueTypeIndex /* -1 */,
                                                    QQmlAbstractBinding *,
                                                    WriteFlags flags = DontRemoveBinding);
+    static QQmlAbstractBinding *removeBinding(QObject *object, int coreIndex, int valueTypeIndex /* -1 */);
     static QQmlAbstractBinding *setBindingNoEnable(QObject *, int coreIndex,
                                                            int valueTypeIndex /* -1 */,
                                                            QQmlAbstractBinding *);
@@ -132,6 +133,7 @@ public:
     static QQmlAbstractBinding *setBinding(const QQmlProperty &that,
                                                    QQmlAbstractBinding *,
                                                    WriteFlags flags = DontRemoveBinding);
+    static QQmlAbstractBinding *removeBinding(const QQmlProperty &that);
     static QQmlBoundSignalExpression *signalExpression(const QQmlProperty &that);
     static QQmlBoundSignalExpressionPointer setSignalExpression(const QQmlProperty &that,
                                                                 QQmlBoundSignalExpression *);
diff --git a/src/qml/qml/qqmlvmemetaobject.cpp b/src/qml/qml/qqmlvmemetaobject.cpp
index 01b37798f8..12600229a9 100644
--- a/src/qml/qml/qqmlvmemetaobject.cpp
+++ b/src/qml/qml/qqmlvmemetaobject.cpp
@@ -875,7 +875,7 @@ int QQmlVMEMetaObject::metaCall(QMetaObject::Call c, int _id, void **a)
                     if (flags & QQmlPropertyPrivate::RemoveBindingOnAliasWrite) {
                         QQmlData *targetData = QQmlData::get(target);
                         if (targetData && targetData->hasBindingBit(d->propertyIndex())) {
-                            QQmlAbstractBinding *binding = QQmlPropertyPrivate::setBinding(target, d->propertyIndex(), d->isValueTypeAlias()?d->valueTypeIndex():-1, 0);
+                            QQmlAbstractBinding *binding = QQmlPropertyPrivate::removeBinding(target, d->propertyIndex(), d->isValueTypeAlias() ? d->valueTypeIndex() : -1);
                             if (binding) binding->destroy();
                         }
                     }