Unify QMetaType::TypeFlags detection.

Duplicated code was removed. As an side effect:
- one runtime flag check was replaced by a compile time check.
- is enum flag can be used together with built-in types.

Change-Id: I54173e7b07ce7e487d3cc21ba24dcccd28b5d049
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>

3 files changed, 15 insertions, 21 deletions

diff --git a/src/corelib/kernel/qmetatype.cpp b/src/corelib/kernel/qmetatype.cpp
index 5032cf9590..98f53f7dd1 100644
--- a/src/corelib/kernel/qmetatype.cpp
+++ b/src/corelib/kernel/qmetatype.cpp
@@ -1578,13 +1578,9 @@ class Flags
     template<typename T, bool IsAcceptedType = DefinedTypesFilter::Acceptor<T>::IsAccepted>
     struct FlagsImpl
     {
-        static quint32 Flags(const int type)
+        static quint32 Flags(const int /* type */)
         {
-            return (!QTypeInfo<T>::isStatic * QMetaType::MovableType)
-                    | (QTypeInfo<T>::isComplex * QMetaType::NeedsConstruction)
-                    | (QTypeInfo<T>::isComplex * QMetaType::NeedsDestruction)
-                    | (type == QMetaType::QObjectStar ? QMetaType::PointerToQObject : 0)
-                    | (type == QMetaType::QWidgetStar ? QMetaType::PointerToQObject : 0);
+            return QtPrivate::QMetaTypeTypeFlags<T>::Flags;
         }
     };
     template<typename T>
diff --git a/src/corelib/kernel/qmetatype.h b/src/corelib/kernel/qmetatype.h
index 0010c27beb..bf1b126200 100644
--- a/src/corelib/kernel/qmetatype.h
+++ b/src/corelib/kernel/qmetatype.h
@@ -435,6 +435,17 @@ namespace QtPrivate {
     template <class Result, class Arg0> struct IsPointerToTypeDerivedFromQObject<Result(*)(Arg0)> { enum { Value = false }; };
     template <class Result, class Arg0, class Arg1> struct IsPointerToTypeDerivedFromQObject<Result(*)(Arg0, Arg1)> { enum { Value = false }; };
     template <class Result, class Arg0, class Arg1, class Arg2> struct IsPointerToTypeDerivedFromQObject<Result(*)(Arg0, Arg1, Arg2)> { enum { Value = false }; };
+
+    template<typename T>
+    struct QMetaTypeTypeFlags
+    {
+        enum { Flags = (!QTypeInfo<T>::isStatic ? QMetaType::MovableType : 0)
+                     | (QTypeInfo<T>::isComplex ? QMetaType::NeedsConstruction : 0)
+                     | (QTypeInfo<T>::isComplex ? QMetaType::NeedsDestruction : 0)
+                     | (IsPointerToTypeDerivedFromQObject<T>::Value ? QMetaType::PointerToQObject : 0)
+                     | (Q_IS_ENUM(T) ? QMetaType::IsEnumeration : 0)
+             };
+    };
 }
 
 template <typename T>
@@ -448,18 +459,7 @@ int qRegisterMetaType(const char *typeName
     if (typedefOf != -1)
         return QMetaType::registerTypedef(typeName, typedefOf);
 
-    QMetaType::TypeFlags flags;
-    if (!QTypeInfo<T>::isStatic)
-        flags |= QMetaType::MovableType;
-    if (QTypeInfo<T>::isComplex) {
-        flags |= QMetaType::NeedsConstruction;
-        flags |= QMetaType::NeedsDestruction;
-    }
-    if (QtPrivate::IsPointerToTypeDerivedFromQObject<T>::Value)
-        flags |= QMetaType::PointerToQObject;
-    if (Q_IS_ENUM(T))
-        flags |= QMetaType::IsEnumeration;
-
+    QMetaType::TypeFlags flags(QtPrivate::QMetaTypeTypeFlags<T>::Flags);
     return QMetaType::registerType(typeName, qMetaTypeDeleteHelper<T>,
                                    qMetaTypeCreateHelper<T>,
                                    qMetaTypeDestructHelper<T>,
diff --git a/src/corelib/kernel/qmetatype_p.h b/src/corelib/kernel/qmetatype_p.h
index b50521c7a6..c73f8d0a20 100644
--- a/src/corelib/kernel/qmetatype_p.h
+++ b/src/corelib/kernel/qmetatype_p.h
@@ -155,9 +155,7 @@ public:
     /*constructor*/(qMetaTypeConstructHelper<Type>), \
     /*destructor*/(qMetaTypeDestructHelper<Type>), \
     /*size*/(QTypeInfo<Type>::sizeOf), \
-    /*flags*/(!QTypeInfo<Type>::isStatic * QMetaType::MovableType) \
-            | (QTypeInfo<Type>::isComplex * QMetaType::NeedsConstruction) \
-            | (QTypeInfo<Type>::isComplex * QMetaType::NeedsDestruction) \
+    /*flags*/QtPrivate::QMetaTypeTypeFlags<Type>::Flags \
 }