Reimplement QVariant to QDebug streaming.

New implementation fixes some commented code marked as FIXME.

Change-Id: If8f5bebedd65bcf8f839d804c2022ca79ef82ddf
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 51 insertions, 0 deletions

diff --git a/src/corelib/kernel/qvariant_p.h b/src/corelib/kernel/qvariant_p.h
index b79d4623c1..015ca5b464 100644
--- a/src/corelib/kernel/qvariant_p.h
+++ b/src/corelib/kernel/qvariant_p.h
@@ -58,6 +58,9 @@
 
 #include <QtCore/qglobal.h>
 #include <QtCore/qvariant.h>
+#include <QtCore/private/qmetatype_p.h>
+#include <QtCore/qdebug.h>
+
 #include "qmetatypeswitcher_p.h"
 
 QT_BEGIN_NAMESPACE
@@ -418,6 +421,54 @@ Q_CORE_EXPORT void registerHandler(const int /* Modules::Names */ name, const QV
 Q_CORE_EXPORT void unregisterHandler(const int /* Modules::Names */ name);
 }
 
+#if !defined(QT_NO_DEBUG_STREAM) && !defined(Q_BROKEN_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 *d)
+        {
+            dbg.nospace() << "QVariant::Type(" << d->type << ")";
+        }
+    };
+
+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);
+    }
+
+    void delegate(const QMetaTypeSwitcher::UnknownType*)
+    {
+        if (m_d->type == QVariant::UserType)
+            m_debugStream.nospace() << "QVariant::UserType";
+        else
+            qWarning("Trying to stream an instance of an invalid type, type id: %i", m_d->type);
+    }
+    void delegate(const void*)
+    {
+        m_debugStream.nospace() << "QVariant::Invalid";
+    }
+private:
+    QDebug m_debugStream;
+    QVariant::Private *m_d;
+};
+#endif
+
 QT_END_NAMESPACE
 
 #endif // QVARIANT_P_H