Get rid of the old QVariant conversion codepath

All conversions do now happen through QMetaType::convert().

Change-Id: I70f7a883262087768acccf8361d34c0490ff2b43
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/kernel/qmetatype.cpp

@@ -1236,6 +1236,10 @@ static const struct : QMetaTypeModuleHelper
             result = QCborValue(QCborValue::Null);
             return true;
         );
+        QMETATYPE_CONVERTER(Nullptr, QCborValue,
+            result = nullptr;
+            return source.isNull();
+        );
         QMETATYPE_CONVERTER_ASSIGN(QCborValue, Bool);
         QMETATYPE_CONVERTER_ASSIGN(QCborValue, Int);
         QMETATYPE_CONVERTER_ASSIGN(QCborValue, UInt);
@@ -1423,7 +1427,12 @@ static const struct : QMetaTypeModuleHelper
         QMETATYPE_CONVERTER(QJsonValue, Nullptr,
             Q_UNUSED(source);
             result = QJsonValue(QJsonValue::Null);
-            return true;);
+            return true;
+        );
+        QMETATYPE_CONVERTER(Nullptr, QJsonValue,
+            result = nullptr;
+            return source.isNull();
+        );
         QMETATYPE_CONVERTER(QJsonValue, Bool,
             result = QJsonValue(source);
             return true;);
@@ -1842,6 +1851,13 @@ bool QMetaType::convert(const void *from, int fromTypeId, void *to, int toTypeId
     QMetaType toType(toTypeId);
     if (toType.flags() & QMetaType::IsEnumeration)
         return convertToEnum(from, fromTypeId, to, toType);
+    if (toTypeId == Nullptr) {
+        *static_cast<std::nullptr_t *>(to) = nullptr;
+        if (fromType.flags() & QMetaType::IsPointer) {
+            if (*static_cast<const void * const *>(from) == nullptr)
+                return true;
+        }
+    }
     return false;
 }
 

src/corelib/kernel/qvariant.cpp

@@ -245,36 +245,6 @@ static qreal qConvertToRealNumber(const QVariant::Private *d, bool *ok)
     }
 }
 
-/*!
- \internal
-
- Converts \a d to type \a t, which is placed in \a result.
- */
-static bool convert(const QVariant::Private *d, int t, void *result)
-{
-    Q_ASSERT(d->typeId() != t);
-    Q_ASSERT(result);
-
-    switch (uint(t)) {
-    case QMetaType::Nullptr:
-        *static_cast<std::nullptr_t *>(result) = nullptr;
-        if (QMetaType::typeFlags(t) & (QMetaType::PointerToGadget | QMetaType::PointerToQObject)
-            || d->typeId() == QMetaType::VoidStar) {
-            if (d->get<const void *>() == nullptr)
-                break;
-        }
-#ifndef QT_BOOTSTRAPPED
-        if (d->typeId() == QMetaType::QCborValue && d->get<QCborValue>().isNull())
-            break;
-#endif
-        return false;
-
-    default:
-        return false;
-    }
-    return true;
-}
-
 // the type of d has already been set, but other field are not set
 static void customConstruct(QVariant::Private *d, const void *copy)
 {
@@ -1391,11 +1361,7 @@ inline T qVariantToHelper(const QVariant::Private &d)
         return d.get<T>();
 
     T ret;
-    const void * const from = d.storage();
-    if (QMetaType::convert(from, d.typeId(), &ret, targetType.id()))
-        return ret;
-
-    convert(&d, targetType.id(), &ret);
+    QMetaType::convert(d.storage(), d.typeId(), &ret, targetType.id());
     return ret;
 }
 
@@ -1823,10 +1789,7 @@ inline T qNumVariantToHelper(const QVariant::Private &d, bool *ok, const T& val)
         return val;
 
     T ret = 0;
-    if (QMetaType::convert(d.storage(), d.typeId(), &ret, t))
-        return ret;
-
-    bool success = convert(&d, t, &ret);
+    bool success = QMetaType::convert(d.storage(), d.typeId(), &ret, t);
     if (ok)
         *ok = success;
     return ret;
@@ -1928,12 +1891,7 @@ bool QVariant::toBool() const
         return d.get<bool>();
 
     bool res = false;
-
-    if (QMetaType::convert(constData(), d.typeId(), &res, QMetaType::Bool))
-        return res;
-
-    ::convert(&d, Bool, &res);
-
+    QMetaType::convert(constData(), d.typeId(), &res, QMetaType::Bool);
     return res;
 }
 
@@ -2469,13 +2427,9 @@ bool QVariant::convert(int targetTypeId)
         return true;
     }
 
-    bool isOk = false;
-    isOk = QMetaType::convert(oldValue.constData(), oldValue.d.typeId(), data(), targetTypeId);
-    if (!isOk)
-        isOk = ::convert(&oldValue.d, targetTypeId, data());
-
-    d.is_null = !isOk;
-    return isOk;
+    bool ok = QMetaType::convert(oldValue.constData(), oldValue.d.typeId(), data(), targetTypeId);
+    d.is_null = !ok;
+    return ok;
 }
 
 /*!
@@ -2485,9 +2439,7 @@ bool QVariant::convert(int targetTypeId)
 */
 bool QVariant::convert(const int type, void *ptr) const
 {
-    if (QMetaType::convert(constData(), d.typeId(), ptr, type))
-        return true;
-    return ::convert(&d, type, ptr);
+    return QMetaType::convert(constData(), d.typeId(), ptr, type);
 }