Fix QDebug cumulating operator<< with many Q_ENUM

The problem is that the operator<< was taking a non-const reference to the QDebug
object. This causes a problem as all other operator<< return a temporary.
Since every other roperator<< takes the QDebug by value, we should also take it by value
in this case.

Move the operator<< in qdebug.h because i don't want to #include qdebug.h from qobject.h
And move the qt_QMetaEnum_debugOperator to be in the corresponding .cpp

Task-number: QTBUG-44462
Change-Id: Ia01629224c58930c2997e767efc43de90d6309e2
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@theqtcompany.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/src/corelib/io/qdebug.cpp b/src/corelib/io/qdebug.cpp
index b0ee715c75..7b49505228 100644
--- a/src/corelib/io/qdebug.cpp
+++ b/src/corelib/io/qdebug.cpp
@@ -40,6 +40,7 @@
 #endif
 
 #include "qdebug.h"
+#include "qmetaobject.h"
 #include <private/qtextstream_p.h>
 #include <private/qtools_p.h>
 
@@ -643,4 +644,23 @@ QDebugStateSaver::~QDebugStateSaver()
     d->restoreState();
 }
 
+#ifndef QT_NO_QOBJECT
+/*!
+    \internal
+ */
+QDebug qt_QMetaEnum_debugOperator(QDebug &dbg, int value, const QMetaObject *meta, const char *name)
+{
+    QDebugStateSaver saver(dbg);
+    QMetaEnum me = meta->enumerator(meta->indexOfEnumerator(name));
+    const char *key = me.valueToKey(value);
+    dbg.nospace() << meta->className() << "::" << name << '(';
+    if (key)
+        dbg << key;
+    else
+        dbg << value;
+    dbg << ')';
+    return dbg;
+}
+#endif
+
 QT_END_NAMESPACE