Get rid of the custom debug stream handling in QVariant

Use the builtin support in QMetaType instead.

Change-Id: Ifc0e88719a384aa7fb525652bada22b6f7ee1c45
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

src/corelib/kernel/qvariant.cpp

@@ -1378,35 +1378,13 @@ static bool convert(const QVariant::Private *d, int t, void *result, bool *ok)
     return true;
 }
 
-#if !defined(QT_NO_DEBUG_STREAM)
-static void streamDebug(QDebug dbg, const QVariant &v)
-{
-    QVariant::Private *d = const_cast<QVariant::Private *>(&v.data_ptr());
-    QVariantDebugStream<CoreTypesFilter> stream(dbg, d);
-    QMetaTypeSwitcher::switcher<void>(stream, d->type().id());
-}
-#endif
-
 const QVariant::Handler qt_kernel_variant_handler = {
-    convert,
-#if !defined(QT_NO_DEBUG_STREAM)
-    streamDebug
-#else
-    nullptr
-#endif
+    convert
 };
 
 static bool dummyConvert(const QVariant::Private *, int, void *, bool *) { Q_ASSERT_X(false, "QVariant", "Trying to convert an unknown type"); return false; }
-#if !defined(QT_NO_DEBUG_STREAM)
-static void dummyStreamDebug(QDebug, const QVariant &) { Q_ASSERT_X(false, "QVariant", "Trying to convert an unknown type"); }
-#endif
 const QVariant::Handler qt_dummy_variant_handler = {
     dummyConvert,
-#if !defined(QT_NO_DEBUG_STREAM)
-    dummyStreamDebug
-#else
-    nullptr
-#endif
 };
 
 // the type of d has already been set, but other field are not set
@@ -1464,26 +1442,8 @@ static bool customConvert(const QVariant::Private *d, int t, void *result, bool
     return convert(d, t, result, ok);
 }
 
-#if !defined(QT_NO_DEBUG_STREAM)
-static void customStreamDebug(QDebug dbg, const QVariant &variant) {
-#ifndef QT_BOOTSTRAPPED
-    QMetaType::TypeFlags flags = QMetaType::typeFlags(variant.userType());
-    if (flags & QMetaType::PointerToQObject)
-        dbg.nospace() << qvariant_cast<QObject*>(variant);
-#else
-    Q_UNUSED(dbg);
-    Q_UNUSED(variant);
-#endif
-}
-#endif
-
 const QVariant::Handler qt_custom_variant_handler = {
-    customConvert,
-#if !defined(QT_NO_DEBUG_STREAM)
-    customStreamDebug
-#else
-    nullptr
-#endif
+    customConvert
 };
 
 } // annonymous used to hide QVariant handlers
@@ -3975,16 +3935,9 @@ QDebug operator<<(QDebug dbg, const QVariant &v)
     dbg.nospace() << "QVariant(";
     if (typeId != QMetaType::UnknownType) {
         dbg << QMetaType::typeName(typeId) << ", ";
-        bool userStream = false;
-        bool canConvertToString = false;
-        if (typeId >= QMetaType::User) {
-            userStream = v.d.type().debugStream(dbg, constData(v.d));
-            canConvertToString = v.canConvert<QString>();
-        }
-        if (!userStream && canConvertToString)
+        bool streamed = v.d.type().debugStream(dbg, constData(v.d));
+        if (!streamed && v.canConvert<QString>())
             dbg << v.toString();
-        else if (!userStream)
-            handlerManager[typeId]->debugStream(dbg, v);
     } else {
         dbg << "Invalid";
     }

src/corelib/kernel/qvariant.h

@@ -469,10 +469,8 @@ class Q_CORE_EXPORT QVariant
     };
  public:
     typedef bool (*f_convert)(const QVariant::Private *d, int t, void *, bool *);
-    typedef void (*f_debugStream)(QDebug, const QVariant &);
     struct Handler {
         f_convert convert;
-        f_debugStream debugStream;
     };
 
     inline bool operator==(const QVariant &v) const

src/corelib/kernel/qvariant_p.h

@@ -55,7 +55,6 @@
 #include <QtCore/qglobal.h>
 #include <QtCore/qvariant.h>
 #include <QtCore/private/qmetatype_p.h>
-#include <QtCore/qdebug.h>
 
 #include "qmetatypeswitcher_p.h"
 
@@ -188,55 +187,6 @@ namespace QVariantPrivate {
 Q_CORE_EXPORT void registerHandler(const int /* Modules::Names */ name, const QVariant::Handler *handler);
 }
 
-#if !defined(QT_NO_DEBUG_STREAM)
-template<class Filter>
-class QVariantDebugStream
-{
-    template<typename T, bool IsAcceptedType = Filter::template Acceptor<T>::IsAccepted>
-    struct Filtered {
-        Filtered(QDebug dbg, QVariant::Private *d)
-        {
-            dbg.nospace() << *v_cast<T>(d);
-        }
-    };
-    template<typename T>
-    struct Filtered<T, /* IsAcceptedType = */ false> {
-        Filtered(QDebug /* dbg */, QVariant::Private *)
-        {
-            // It is not possible to construct not acccepted type, QVariantConstructor creates an invalid variant for them
-            Q_ASSERT(false);
-        }
-    };
-
-public:
-    QVariantDebugStream(QDebug dbg, QVariant::Private *d)
-        : m_debugStream(dbg)
-        , m_d(d)
-    {}
-
-    template<typename T>
-    void delegate(const T*)
-    {
-        Filtered<T> streamIt(m_debugStream, m_d);
-        Q_UNUSED(streamIt);
-    }
-
-    void delegate(const QMetaTypeSwitcher::NotBuiltinType*)
-    {
-        // QVariantDebugStream class is used only for a built-in type
-        Q_ASSERT(false);
-    }
-    void delegate(const QMetaTypeSwitcher::UnknownType*)
-    {
-        m_debugStream.nospace() << "QVariant::Invalid";
-    }
-    void delegate(const void*) { Q_ASSERT(false); }
-private:
-    QDebug m_debugStream;
-    QVariant::Private *m_d;
-};
-#endif
-
 QT_END_NAMESPACE
 
 #endif // QVARIANT_P_H

src/gui/kernel/qguivariant.cpp

@@ -233,22 +233,8 @@ static bool convert(const QVariant::Private *d, int t,
     return qcoreVariantHandler()->convert(d, t, result, ok);
 }
 
-#if !defined(QT_NO_DEBUG_STREAM)
-static void streamDebug(QDebug dbg, const QVariant &v)
-{
-    QVariant::Private *d = const_cast<QVariant::Private *>(&v.data_ptr());
-    QVariantDebugStream<GuiTypesFilter> stream(dbg, d);
-    QMetaTypeSwitcher::switcher<void>(stream, d->type().id(), nullptr);
-}
-#endif
-
 const QVariant::Handler qt_gui_variant_handler = {
-    convert,
-#if !defined(QT_NO_DEBUG_STREAM)
-    streamDebug
-#else
-    nullptr
-#endif
+    convert
 };
 
 #define QT_IMPL_METATYPEINTERFACE_GUI_TYPES(MetaTypeName, MetaTypeId, RealName) \

src/widgets/kernel/qwidgetsvariant.cpp

@@ -59,27 +59,8 @@ static bool convert(const QVariant::Private *d, int type, void *result, bool *ok
     return false;
 }
 
-#if !defined(QT_NO_DEBUG_STREAM)
-static void streamDebug(QDebug dbg, const QVariant &v)
-{
-    QVariant::Private *d = const_cast<QVariant::Private *>(&v.data_ptr());
-    switch (d->type().id()) {
-    case QMetaType::QSizePolicy:
-        dbg.nospace() << *v_cast<QSizePolicy>(d);
-        break;
-    default:
-        dbg.nospace() << "QMetaType::Type(" << d->type().id() << ')';
-    }
-}
-#endif
-
 static const QVariant::Handler widgets_handler = {
-    convert,
-#if !defined(QT_NO_DEBUG_STREAM)
-    streamDebug
-#else
-    nullptr
-#endif
+    convert
 };
 
 static const struct : QMetaTypeModuleHelper