Add FINAL attribute to Q_PROPERTY()

This will be used by the declarative module to optimize property bindings.

Reviewed-by: Roberto Raggi

8 files changed, 50 insertions, 4 deletions

diff --git a/doc/src/properties.qdoc b/doc/src/properties.qdoc
index cac5016..2d03e91 100644
--- a/doc/src/properties.qdoc
+++ b/doc/src/properties.qdoc
@@ -128,6 +128,11 @@
     constant value may be different for different instances of the object.  A
     constant property cannot have a WRTE method or a NOTIFY signal.
 
+    \o The presence of the \c FINAL attribute indicates that the property
+    will not be overridden by a derived class.  This can be used for performance
+    optimizations in some cases, but is not enforced by moc.  Care must be taken
+    never to override a \c FINAL property.
+
     \endlist
 
     The \c READ, \c WRITE, and \c RESET functions can be inherited.
diff --git a/doc/src/snippets/code/doc_src_properties.qdoc b/doc/src/snippets/code/doc_src_properties.qdoc
index 64e5377..3c9109f 100644
--- a/doc/src/snippets/code/doc_src_properties.qdoc
+++ b/doc/src/snippets/code/doc_src_properties.qdoc
@@ -8,7 +8,8 @@ Q_PROPERTY(type name
            [SCRIPTABLE bool]
            [STORED bool]
 	   [USER bool]
-           [CONSTANT])
+           [CONSTANT]
+           [FINAL])
 //! [0]
 
 
diff --git a/src/corelib/kernel/qmetaobject.cpp b/src/corelib/kernel/qmetaobject.cpp
index fee2da9..3b09061 100644
--- a/src/corelib/kernel/qmetaobject.cpp
+++ b/src/corelib/kernel/qmetaobject.cpp
@@ -161,7 +161,8 @@ enum PropertyFlags  {
     ResolveUser = 0x00200000,
     Notify = 0x00400000,
     Dynamic = 0x00800000,
-    Constant = 0x00000400
+    Constant = 0x00000400,
+    Final = 0x00000800
 };
 
 enum MethodFlags  {
@@ -2466,6 +2467,20 @@ bool QMetaProperty::isConstant() const
 }
 
 /*!
+    Returns true if the property is final; otherwise returns false.
+
+    A property is final if the \c{Q_PROPERTY()}'s \c FINAL attribute
+    is set.
+*/
+bool QMetaProperty::isFinal() const
+{
+    if (!mobj)
+        return false;
+    int flags = mobj->d.data[handle + 2];
+    return flags & Final;
+}
+
+/*!
     \obsolete
 
     Returns true if the property is editable for the given \a object;
diff --git a/src/corelib/kernel/qmetaobject.h b/src/corelib/kernel/qmetaobject.h
index 73b52a9..bd47582 100644
--- a/src/corelib/kernel/qmetaobject.h
+++ b/src/corelib/kernel/qmetaobject.h
@@ -189,6 +189,7 @@ public:
     bool isUser(const QObject *obj = 0) const;
     bool isDynamic() const;
     bool isConstant() const;
+    bool isFinal() const;
 
     bool isFlagType() const;
     bool isEnumType() const;
diff --git a/src/tools/moc/generator.cpp b/src/tools/moc/generator.cpp
index e4086e6..fbc434d 100644
--- a/src/tools/moc/generator.cpp
+++ b/src/tools/moc/generator.cpp
@@ -68,7 +68,8 @@ enum PropertyFlags  {
     ResolveUser = 0x00200000,
     Notify = 0x00400000,
     Dynamic = 0x00800000,
-    Constant = 0x00000400
+    Constant = 0x00000400,
+    Final = 0x00000800
 };
 enum MethodFlags {
     AccessPrivate = 0x00,
@@ -601,6 +602,8 @@ void Generator::generateProperties()
 
         if (p.constant)
             flags |= Constant;
+        if (p.final)
+            flags |= Final;
 
         fprintf(out, "    %4d, %4d, ",
                 strreg(p.name),
diff --git a/src/tools/moc/moc.cpp b/src/tools/moc/moc.cpp
index 66012ca..aa11d0e 100644
--- a/src/tools/moc/moc.cpp
+++ b/src/tools/moc/moc.cpp
@@ -912,6 +912,9 @@ void Moc::parseProperty(ClassDef *def)
         if (l[0] == 'C' && l == "CONSTANT") {
             propDef.constant = true;
             continue;
+        } else if(l[0] == 'F' && l == "FINAL") {
+            propDef.final = true;
+            continue;
         }
 
         QByteArray v, v2;
diff --git a/src/tools/moc/moc.h b/src/tools/moc/moc.h
index 494d53e..767f84e 100644
--- a/src/tools/moc/moc.h
+++ b/src/tools/moc/moc.h
@@ -115,10 +115,11 @@ struct FunctionDef
 
 struct PropertyDef
 {
-    PropertyDef():notifyId(-1), constant(false), gspec(ValueSpec){}
+    PropertyDef():notifyId(-1), constant(false), final(false), gspec(ValueSpec){}
     QByteArray name, type, read, write, reset, designable, scriptable, editable, stored, user, notify;
     int notifyId;
     bool constant;
+    bool final;
     enum Specification  { ValueSpec, ReferenceSpec, PointerSpec };
     Specification gspec;
     bool stdCppSet() const {
diff --git a/tests/auto/qmetaobject/tst_qmetaobject.cpp b/tests/auto/qmetaobject/tst_qmetaobject.cpp
index f4cff2b..ac2858c 100644
--- a/tests/auto/qmetaobject/tst_qmetaobject.cpp
+++ b/tests/auto/qmetaobject/tst_qmetaobject.cpp
@@ -109,6 +109,7 @@ class tst_QMetaObject : public QObject
     Q_PROPERTY(MyStruct value7 READ value7 WRITE setVal7 NOTIFY value7Changed)
     Q_PROPERTY(int value8 READ value8 NOTIFY value8Changed)
     Q_PROPERTY(int value9 READ value9 CONSTANT)
+    Q_PROPERTY(int value10 READ value10 FINAL)
 
 public:
     enum EnumType { EnumType1 };
@@ -140,6 +141,8 @@ public:
 
     int value9() const { return 1; }
 
+    int value10() const { return 1; }
+
     QList<QVariant> value4;
     QVariantList value5;
 
@@ -163,6 +166,7 @@ private slots:
     void checkScope();
     void propertyNotify();
     void propertyConstant();
+    void propertyFinal();
 
     void stdSet();
     void classInfo();
@@ -802,6 +806,19 @@ void tst_QMetaObject::propertyConstant()
     QVERIFY(prop.isConstant());
 }
 
+void tst_QMetaObject::propertyFinal()
+{
+    const QMetaObject *mo = metaObject();
+
+    QMetaProperty prop = mo->property(mo->indexOfProperty("value10"));
+    QVERIFY(prop.isValid());
+    QVERIFY(prop.isFinal());
+
+    prop = mo->property(mo->indexOfProperty("value9"));
+    QVERIFY(prop.isValid());
+    QVERIFY(!prop.isFinal());
+}
+
 class ClassInfoTestObjectA : public QObject
 {
     Q_OBJECT