QtDBus: Convert some loops to ranged for loops

Convert some loops that are using Java-style iterators into
ranged for loops for better readability.

Change-Id: I14f6339608d201fe06a753be236db52815cbf5c4
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

9 files changed, 86 insertions, 154 deletions

diff --git a/src/dbus/qdbusabstractadaptor.cpp b/src/dbus/qdbusabstractadaptor.cpp
index 717707ae9c..77e86ed949 100644
--- a/src/dbus/qdbusabstractadaptor.cpp
+++ b/src/dbus/qdbusabstractadaptor.cpp
@@ -37,11 +37,9 @@ QDBusAdaptorConnector *qDBusFindAdaptorConnector(QObject *obj)
 {
     if (!obj)
         return nullptr;
-    const QObjectList &children = obj->children();
-    QObjectList::ConstIterator it = children.constBegin();
-    QObjectList::ConstIterator end = children.constEnd();
-    for ( ; it != end; ++it) {
-        QDBusAdaptorConnector *connector = qobject_cast<QDBusAdaptorConnector *>(*it);
+
+    for (QObject *child : std::as_const(obj->children())) {
+        QDBusAdaptorConnector *connector = qobject_cast<QDBusAdaptorConnector *>(child);
         if (connector) {
             connector->polish();
             return connector;
@@ -227,11 +225,8 @@ void QDBusAdaptorConnector::polish()
         return;                 // avoid working multiple times if multiple adaptors were added
 
     waitingForPolish = false;
-    const QObjectList &objs = parent()->children();
-    QObjectList::ConstIterator it = objs.constBegin();
-    QObjectList::ConstIterator end = objs.constEnd();
-    for ( ; it != end; ++it) {
-        QDBusAbstractAdaptor *adaptor = qobject_cast<QDBusAbstractAdaptor *>(*it);
+    for (QObject *child : std::as_const(parent()->children())) {
+        QDBusAbstractAdaptor *adaptor = qobject_cast<QDBusAbstractAdaptor *>(child);
         if (adaptor)
             addAdaptor(adaptor);
     }
diff --git a/src/dbus/qdbusargument.h b/src/dbus/qdbusargument.h
index 475c47f442..f1ecb91f0d 100644
--- a/src/dbus/qdbusargument.h
+++ b/src/dbus/qdbusargument.h
@@ -222,10 +222,8 @@ inline const QDBusArgument &operator>>(const QDBusArgument &arg, Container<T> &l
 inline QDBusArgument &operator<<(QDBusArgument &arg, const QVariantList &list)
 {
     arg.beginArray(QMetaType::fromType<QDBusVariant>());
-    QVariantList::ConstIterator it = list.constBegin();
-    QVariantList::ConstIterator end = list.constEnd();
-    for ( ; it != end; ++it)
-        arg << QDBusVariant(*it);
+    for (const QVariant &value : list)
+        arg << QDBusVariant(value);
     arg.endArray();
     return arg;
 }
@@ -284,11 +282,9 @@ inline const QDBusArgument &operator>>(const QDBusArgument &arg, Container<Key,
 inline QDBusArgument &operator<<(QDBusArgument &arg, const QVariantMap &map)
 {
     arg.beginMap(QMetaType::fromType<QString>(), QMetaType::fromType<QDBusVariant>());
-    QVariantMap::ConstIterator it = map.constBegin();
-    QVariantMap::ConstIterator end = map.constEnd();
-    for ( ; it != end; ++it) {
+    for (const auto &[key, value] : map.asKeyValueRange()) {
         arg.beginMapEntry();
-        arg << it.key() << QDBusVariant(it.value());
+        arg << key << QDBusVariant(value);
         arg.endMapEntry();
     }
     arg.endMap();
@@ -298,11 +294,9 @@ inline QDBusArgument &operator<<(QDBusArgument &arg, const QVariantMap &map)
 inline QDBusArgument &operator<<(QDBusArgument &arg, const QVariantHash &map)
 {
     arg.beginMap(QMetaType::fromType<QString>(), QMetaType::fromType<QDBusVariant>());
-    QVariantHash::ConstIterator it = map.constBegin();
-    QVariantHash::ConstIterator end = map.constEnd();
-    for ( ; it != end; ++it) {
+    for (const auto &[key, value] : map.asKeyValueRange()) {
         arg.beginMapEntry();
-        arg << it.key() << QDBusVariant(it.value());
+        arg << key << QDBusVariant(value);
         arg.endMapEntry();
     }
     arg.endMap();
diff --git a/src/dbus/qdbusconnection.cpp b/src/dbus/qdbusconnection.cpp
index 2203f047b1..cebbc23d7d 100644
--- a/src/dbus/qdbusconnection.cpp
+++ b/src/dbus/qdbusconnection.cpp
@@ -124,9 +124,7 @@ void QDBusConnectionManager::run()
 
     // cleanup:
     const auto locker = qt_scoped_lock(mutex);
-    for (QHash<QString, QDBusConnectionPrivate *>::const_iterator it = connectionHash.constBegin();
-         it != connectionHash.constEnd(); ++it) {
-        QDBusConnectionPrivate *d = it.value();
+    for (QDBusConnectionPrivate *d : std::as_const(connectionHash)) {
         if (!d->ref.deref()) {
             delete d;
         } else {
diff --git a/src/dbus/qdbusintegrator.cpp b/src/dbus/qdbusintegrator.cpp
index 5f95465b30..bd4b46fbda 100644
--- a/src/dbus/qdbusintegrator.cpp
+++ b/src/dbus/qdbusintegrator.cpp
@@ -409,17 +409,14 @@ static QObject *findChildObject(const QDBusConnectionPrivate::ObjectTreeNode *ro
             pos = (pos == -1 ? length : pos);
             auto pathComponent = QStringView{fullpath}.mid(start, pos - start);
 
-            const QObjectList children = obj->children();
-
             // find a child with the proper name
             QObject *next = nullptr;
-            QObjectList::ConstIterator it = children.constBegin();
-            QObjectList::ConstIterator end = children.constEnd();
-            for ( ; it != end; ++it)
-                if ((*it)->objectName() == pathComponent) {
-                    next = *it;
+            for (QObject *child : std::as_const(obj->children())) {
+                if (child->objectName() == pathComponent) {
+                    next = child;
                     break;
                 }
+            }
 
             if (!next)
                 break;
@@ -561,7 +558,7 @@ bool QDBusConnectionPrivate::handleMessage(const QDBusMessage &amsg)
 
 static void huntAndDestroy(QObject *needle, QDBusConnectionPrivate::ObjectTreeNode &haystack)
 {
-    for (auto &node : haystack.children)
+    for (QDBusConnectionPrivate::ObjectTreeNode &node : haystack.children)
         huntAndDestroy(needle, node);
 
     auto isInactive = [](const QDBusConnectionPrivate::ObjectTreeNode &node) { return !node.isActive(); };
@@ -605,11 +602,11 @@ static void huntAndEmit(DBusConnection *connection, DBusMessage *msg,
                         QObject *needle, const QDBusConnectionPrivate::ObjectTreeNode &haystack,
                         bool isScriptable, bool isAdaptor, const QString &path = QString())
 {
-    QDBusConnectionPrivate::ObjectTreeNode::DataList::ConstIterator it = haystack.children.constBegin();
-    QDBusConnectionPrivate::ObjectTreeNode::DataList::ConstIterator end = haystack.children.constEnd();
-    for ( ; it != end; ++it) {
-        if (it->isActive())
-            huntAndEmit(connection, msg, needle, *it, isScriptable, isAdaptor, path + u'/' + it->name);
+    for (const QDBusConnectionPrivate::ObjectTreeNode &node : std::as_const(haystack.children)) {
+        if (node.isActive()) {
+            huntAndEmit(connection, msg, needle, node, isScriptable, isAdaptor,
+                        path + u'/' + node.name);
+        }
     }
 
     if (needle == haystack.obj) {
@@ -1074,12 +1071,8 @@ QDBusConnectionPrivate::~QDBusConnectionPrivate()
 void QDBusConnectionPrivate::collectAllObjects(QDBusConnectionPrivate::ObjectTreeNode &haystack,
                                                QSet<QObject *> &set)
 {
-    QDBusConnectionPrivate::ObjectTreeNode::DataList::Iterator it = haystack.children.begin();
-
-    while (it != haystack.children.end()) {
-        collectAllObjects(*it, set);
-        it++;
-    }
+    for (ObjectTreeNode &child : haystack.children)
+        collectAllObjects(child, set);
 
     if (haystack.obj)
         set.insert(haystack.obj);
@@ -1107,11 +1100,9 @@ void QDBusConnectionPrivate::closeConnection()
         }
     }
 
-    for (auto it = pendingCalls.begin(); it != pendingCalls.end(); ++it) {
-        auto call = *it;
-        if (!call->ref.deref()) {
+    for (QDBusPendingCallPrivate *call : pendingCalls) {
+        if (!call->ref.deref())
             delete call;
-        }
     }
     pendingCalls.clear();
 
@@ -1122,18 +1113,12 @@ void QDBusConnectionPrivate::closeConnection()
     // dangling pointer.
     QSet<QObject *> allObjects;
     collectAllObjects(rootNode, allObjects);
-    SignalHookHash::const_iterator sit = signalHooks.constBegin();
-    while (sit != signalHooks.constEnd()) {
-        allObjects.insert(sit.value().obj);
-        ++sit;
-    }
+    for (const SignalHook &signalHook : std::as_const(signalHooks))
+        allObjects.insert(signalHook.obj);
 
     // now disconnect ourselves
-    QSet<QObject *>::const_iterator oit = allObjects.constBegin();
-    while (oit != allObjects.constEnd()) {
-        (*oit)->disconnect(this);
-        ++oit;
-    }
+    for (QObject *obj : std::as_const(allObjects))
+        obj->disconnect(this);
 }
 
 void QDBusConnectionPrivate::handleDBusDisconnection()
@@ -1175,11 +1160,9 @@ void QDBusConnectionPrivate::doDispatch()
     if (mode == ClientMode || mode == PeerMode) {
         if (dispatchEnabled && !pendingMessages.isEmpty()) {
             // dispatch previously queued messages
-            PendingMessageList::Iterator it = pendingMessages.begin();
-            PendingMessageList::Iterator end = pendingMessages.end();
-            for ( ; it != end; ++it) {
-                qDBusDebug() << this << "dequeueing message" << *it;
-                handleMessage(std::move(*it));
+            for (QDBusMessage &message : pendingMessages) {
+                qDBusDebug() << this << "dequeueing message" << message;
+                handleMessage(std::move(message));
             }
             pendingMessages.clear();
         }
@@ -1459,14 +1442,11 @@ void QDBusConnectionPrivate::activateObject(ObjectTreeNode &node, const QDBusMes
         if (msg.interface().isEmpty()) {
             // place the call in all interfaces
             // let the first one that handles it to work
-            QDBusAdaptorConnector::AdaptorMap::ConstIterator it =
-                connector->adaptors.constBegin();
-            QDBusAdaptorConnector::AdaptorMap::ConstIterator end =
-                connector->adaptors.constEnd();
-
-            for ( ; it != end; ++it)
-                if (activateCall(it->adaptor, newflags, msg))
+            for (const QDBusAdaptorConnector::AdaptorData &adaptorData :
+                 std::as_const(connector->adaptors)) {
+                if (activateCall(adaptorData.adaptor, newflags, msg))
                     return;
+            }
         } else {
             // check if we have an interface matching the name that was asked:
             QDBusAdaptorConnector::AdaptorMap::ConstIterator it;
diff --git a/src/dbus/qdbusinternalfilters.cpp b/src/dbus/qdbusinternalfilters.cpp
index 57ae0326e7..d860a02180 100644
--- a/src/dbus/qdbusinternalfilters.cpp
+++ b/src/dbus/qdbusinternalfilters.cpp
@@ -76,11 +76,8 @@ static const char peerInterfaceXml[] =
 static QString generateSubObjectXml(QObject *object)
 {
     QString retval;
-    const QObjectList &objs = object->children();
-    QObjectList::ConstIterator it = objs.constBegin();
-    QObjectList::ConstIterator end = objs.constEnd();
-    for ( ; it != end; ++it) {
-        QString name = (*it)->objectName();
+    for (const QObject *child : object->children()) {
+        QString name = child->objectName();
         if (!name.isEmpty() && QDBusUtil::isValidPartOfObjectPath(name))
             retval += "  <node name=\""_L1 + name + "\"/>\n"_L1;
     }
@@ -116,20 +113,22 @@ QString qDBusIntrospectObject(const QDBusConnectionPrivate::ObjectTreeNode &node
             (connector = qDBusFindAdaptorConnector(node.obj))) {
 
             // trasverse every adaptor in this object
-            QDBusAdaptorConnector::AdaptorMap::ConstIterator it = connector->adaptors.constBegin();
-            QDBusAdaptorConnector::AdaptorMap::ConstIterator end = connector->adaptors.constEnd();
-            for ( ; it != end; ++it) {
+            for (const QDBusAdaptorConnector::AdaptorData &adaptorData :
+                 std::as_const(connector->adaptors)) {
                 // add the interface:
-                QString ifaceXml = QDBusAbstractAdaptorPrivate::retrieveIntrospectionXml(it->adaptor);
+                QString ifaceXml =
+                        QDBusAbstractAdaptorPrivate::retrieveIntrospectionXml(adaptorData.adaptor);
                 if (ifaceXml.isEmpty()) {
                     // add the interface's contents:
-                    ifaceXml += qDBusGenerateMetaObjectXml(QString::fromLatin1(it->interface),
-                                                           it->adaptor->metaObject(),
-                                                           &QDBusAbstractAdaptor::staticMetaObject,
-                                                           QDBusConnection::ExportScriptableContents
-                                                           | QDBusConnection::ExportNonScriptableContents);
-
-                    QDBusAbstractAdaptorPrivate::saveIntrospectionXml(it->adaptor, ifaceXml);
+                    ifaceXml += qDBusGenerateMetaObjectXml(
+                            QString::fromLatin1(adaptorData.interface),
+                            adaptorData.adaptor->metaObject(),
+                            &QDBusAbstractAdaptor::staticMetaObject,
+                            QDBusConnection::ExportScriptableContents
+                                    | QDBusConnection::ExportNonScriptableContents);
+
+                    QDBusAbstractAdaptorPrivate::saveIntrospectionXml(adaptorData.adaptor,
+                                                                      ifaceXml);
                 }
 
                 xml_data += ifaceXml;
@@ -151,13 +150,10 @@ QString qDBusIntrospectObject(const QDBusConnectionPrivate::ObjectTreeNode &node
         xml_data += generateSubObjectXml(node.obj);
     } else {
         // generate from the object tree
-        QDBusConnectionPrivate::ObjectTreeNode::DataList::ConstIterator it =
-            node.children.constBegin();
-        QDBusConnectionPrivate::ObjectTreeNode::DataList::ConstIterator end =
-            node.children.constEnd();
-        for ( ; it != end; ++it)
-            if (it->obj || !it->children.isEmpty())
-                xml_data += "  <node name=\""_L1 + it->name + "\"/>\n"_L1;
+        for (const QDBusConnectionPrivate::ObjectTreeNode &node : node.children) {
+            if (node.obj || !node.children.isEmpty())
+                xml_data += "  <node name=\""_L1 + node.name + "\"/>\n"_L1;
+        }
     }
 
     xml_data += "</node>\n"_L1;
@@ -195,7 +191,7 @@ QDBusMessage qDBusPropertyGet(const QDBusConnectionPrivate::ObjectTreeNode &node
     QString interface_name = msg.arguments().at(0).toString();
     QByteArray property_name = msg.arguments().at(1).toString().toUtf8();
 
-    QDBusAdaptorConnector *connector;
+    const QDBusAdaptorConnector *connector;
     QVariant value;
     bool interfaceFound = false;
     if (node.flags & QDBusConnection::ExportAdaptors &&
@@ -204,12 +200,11 @@ QDBusMessage qDBusPropertyGet(const QDBusConnectionPrivate::ObjectTreeNode &node
         // find the class that implements interface_name or try until we've found the property
         // in case of an empty interface
         if (interface_name.isEmpty()) {
-            for (QDBusAdaptorConnector::AdaptorMap::ConstIterator it = connector->adaptors.constBegin(),
-                 end = connector->adaptors.constEnd(); it != end; ++it) {
-                const QMetaObject *mo = it->adaptor->metaObject();
+            for (const QDBusAdaptorConnector::AdaptorData &adaptorData : connector->adaptors) {
+                const QMetaObject *mo = adaptorData.adaptor->metaObject();
                 int pidx = mo->indexOfProperty(property_name);
                 if (pidx != -1) {
-                    value = mo->property(pidx).read(it->adaptor);
+                    value = mo->property(pidx).read(adaptorData.adaptor);
                     break;
                 }
             }
@@ -361,9 +356,9 @@ QDBusMessage qDBusPropertySet(const QDBusConnectionPrivate::ObjectTreeNode &node
         // find the class that implements interface_name or try until we've found the property
         // in case of an empty interface
         if (interface_name.isEmpty()) {
-            for (QDBusAdaptorConnector::AdaptorMap::ConstIterator it = connector->adaptors.constBegin(),
-                 end = connector->adaptors.constEnd(); it != end; ++it) {
-                int status = writeProperty(it->adaptor, property_name, value);
+            for (const QDBusAdaptorConnector::AdaptorData &adaptorData :
+                 std::as_const(connector->adaptors)) {
+                int status = writeProperty(adaptorData.adaptor, property_name, value);
                 if (status == PropertyNotFound)
                     continue;
                 return propertyWriteReply(msg, interface_name, property_name, status);
@@ -401,10 +396,8 @@ QDBusMessage qDBusPropertySet(const QDBusConnectionPrivate::ObjectTreeNode &node
 // unite two QVariantMaps, but don't generate duplicate keys
 static QVariantMap &operator+=(QVariantMap &lhs, const QVariantMap &rhs)
 {
-    QVariantMap::ConstIterator it = rhs.constBegin(),
-                              end = rhs.constEnd();
-    for ( ; it != end; ++it)
-        lhs.insert(it.key(), it.value());
+    for (const auto &[key, value] : rhs.asKeyValueRange())
+        lhs.insert(key, value);
     return lhs;
 }
 
@@ -461,9 +454,10 @@ QDBusMessage qDBusPropertyGetAll(const QDBusConnectionPrivate::ObjectTreeNode &n
 
         if (interface_name.isEmpty()) {
             // iterate over all interfaces
-            for (QDBusAdaptorConnector::AdaptorMap::ConstIterator it = connector->adaptors.constBegin(),
-                 end = connector->adaptors.constEnd(); it != end; ++it) {
-                result += readAllProperties(it->adaptor, QDBusConnection::ExportAllProperties);
+            for (const QDBusAdaptorConnector::AdaptorData &adaptorData :
+                 std::as_const(connector->adaptors)) {
+                result += readAllProperties(adaptorData.adaptor,
+                                            QDBusConnection::ExportAllProperties);
             }
         } else {
             // find the class that implements interface_name
diff --git a/src/dbus/qdbusmarshaller.cpp b/src/dbus/qdbusmarshaller.cpp
index e3fb298fbe..480b19774e 100644
--- a/src/dbus/qdbusmarshaller.cpp
+++ b/src/dbus/qdbusmarshaller.cpp
@@ -206,10 +206,8 @@ inline void QDBusMarshaller::append(const QStringList &arg)
 
     QDBusMarshaller sub(capabilities);
     open(sub, DBUS_TYPE_ARRAY, DBUS_TYPE_STRING_AS_STRING);
-    QStringList::ConstIterator it = arg.constBegin();
-    QStringList::ConstIterator end = arg.constEnd();
-    for ( ; it != end; ++it)
-        sub.append(*it);
+    for (const QString &s : arg)
+        sub.append(s);
     // don't call sub.close(): it auto-closes
 }
 
diff --git a/src/dbus/qdbusmessage.cpp b/src/dbus/qdbusmessage.cpp
index fb3f8600e1..6372fe0496 100644
--- a/src/dbus/qdbusmessage.cpp
+++ b/src/dbus/qdbusmessage.cpp
@@ -155,14 +155,12 @@ DBusMessage *QDBusMessagePrivate::toDBusMessage(const QDBusMessage &message, QDB
     d_ptr->parametersValidated = true;
 
     QDBusMarshaller marshaller(capabilities);
-    QVariantList::ConstIterator it =  d_ptr->arguments.constBegin();
-    QVariantList::ConstIterator cend = d_ptr->arguments.constEnd();
     q_dbus_message_iter_init_append(msg, &marshaller.iterator);
     if (!d_ptr->message.isEmpty())
         // prepend the error message
         marshaller.append(d_ptr->message);
-    for ( ; it != cend; ++it)
-        marshaller.appendVariantInternal(*it);
+    for (const QVariant &argument : std::as_const(d_ptr->arguments))
+        marshaller.appendVariantInternal(argument);
 
     // check if everything is ok
     if (marshaller.ok)
@@ -239,10 +237,8 @@ QDBusMessage QDBusMessagePrivate::makeLocal(const QDBusConnectionPrivate &conn,
 
     // determine if we are carrying any complex types
     QString computedSignature;
-    QVariantList::ConstIterator it = asSent.d_ptr->arguments.constBegin();
-    QVariantList::ConstIterator end = asSent.d_ptr->arguments.constEnd();
-    for ( ; it != end; ++it) {
-        QMetaType id = it->metaType();
+    for (const QVariant &argument : std::as_const(asSent.d_ptr->arguments)) {
+        QMetaType id = argument.metaType();
         const char *signature = QDBusMetaType::typeToSignature(id);
         if ((id.id() != QMetaType::QStringList && id.id() != QMetaType::QByteArray &&
              qstrlen(signature) != 1) || id == QMetaType::fromType<QDBusVariant>()) {
@@ -804,12 +800,10 @@ static QDebug operator<<(QDebug dbg, QDBusMessage::MessageType t)
 static void debugVariantList(QDebug dbg, const QVariantList &list)
 {
     bool first = true;
-    QVariantList::ConstIterator it = list.constBegin();
-    QVariantList::ConstIterator end = list.constEnd();
-    for ( ; it != end; ++it) {
+    for (const QVariant &elem : list) {
         if (!first)
             dbg.nospace() << ", ";
-        dbg.nospace() << qPrintable(QDBusUtil::argumentToString(*it));
+        dbg.nospace() << qPrintable(QDBusUtil::argumentToString(elem));
         first = false;
     }
 }
diff --git a/src/dbus/qdbusmetaobject.cpp b/src/dbus/qdbusmetaobject.cpp
index d2ca9df869..22641c9249 100644
--- a/src/dbus/qdbusmetaobject.cpp
+++ b/src/dbus/qdbusmetaobject.cpp
@@ -208,10 +208,7 @@ void QDBusMetaObjectGenerator::parseMethods()
     //  Add cloned methods when the remote object has return types
     //
 
-    QDBusIntrospection::Methods::ConstIterator method_it = data->methods.constBegin();
-    QDBusIntrospection::Methods::ConstIterator method_end = data->methods.constEnd();
-    for ( ; method_it != method_end; ++method_it) {
-        const QDBusIntrospection::Method &m = *method_it;
+    for (const QDBusIntrospection::Method &m : std::as_const(data->methods)) {
         Method mm;
 
         mm.name = m.name.toLatin1();
@@ -284,10 +281,7 @@ void QDBusMetaObjectGenerator::parseMethods()
 
 void QDBusMetaObjectGenerator::parseSignals()
 {
-    QDBusIntrospection::Signals::ConstIterator signal_it = data->signals_.constBegin();
-    QDBusIntrospection::Signals::ConstIterator signal_end = data->signals_.constEnd();
-    for ( ; signal_it != signal_end; ++signal_it) {
-        const QDBusIntrospection::Signal &s = *signal_it;
+    for (const QDBusIntrospection::Signal &s : std::as_const(data->signals_)) {
         Method mm;
 
         mm.name = s.name.toLatin1();
@@ -331,10 +325,7 @@ void QDBusMetaObjectGenerator::parseSignals()
 
 void QDBusMetaObjectGenerator::parseProperties()
 {
-    QDBusIntrospection::Properties::ConstIterator prop_it = data->properties.constBegin();
-    QDBusIntrospection::Properties::ConstIterator prop_end = data->properties.constEnd();
-    for ( ; prop_it != prop_end; ++prop_it) {
-        const QDBusIntrospection::Property &p = *prop_it;
+    for (const QDBusIntrospection::Property &p : std::as_const(data->properties)) {
         Property mp;
         Type type = findType(p.type.toLatin1(), p.annotations);
         if (type.id == QMetaType::UnknownType)
@@ -363,11 +354,8 @@ void QDBusMetaObjectGenerator::parseProperties()
 qsizetype QDBusMetaObjectGenerator::aggregateParameterCount(const QMap<QByteArray, Method> &map)
 {
     qsizetype sum = 0;
-    QMap<QByteArray, Method>::const_iterator it;
-    for (it = map.constBegin(); it != map.constEnd(); ++it) {
-        const Method &m = it.value();
+    for (const Method &m : map)
         sum += m.inputTypes.size() + qMax(qsizetype(1), m.outputTypes.size());
-    }
     return sum;
 }
 
@@ -444,11 +432,8 @@ void QDBusMetaObjectGenerator::write(QDBusMetaObject *obj)
     qsizetype currentMethodMetaTypeOffset = properties.size() + 1;
     for (int x = 0; x < 2; ++x) {
         // Signals must be added before other methods, to match moc.
-        QMap<QByteArray, Method> &map = (x == 0) ? signals_ : methods;
-        for (QMap<QByteArray, Method>::ConstIterator it = map.constBegin();
-             it != map.constEnd(); ++it) {
-            const Method &mm = it.value();
-
+        const QMap<QByteArray, Method> &map = (x == 0) ? signals_ : methods;
+        for (const Method &mm : map) {
             qsizetype argc = mm.inputTypes.size() + qMax(qsizetype(0), mm.outputTypes.size() - 1);
 
             idata[offset++] = strings.enter(mm.name);
@@ -514,12 +499,9 @@ void QDBusMetaObjectGenerator::write(QDBusMetaObject *obj)
 
     // add each property
     signatureOffset = header->propertyDBusData;
-    for (QMap<QByteArray, Property>::ConstIterator it = properties.constBegin();
-         it != properties.constEnd(); ++it) {
-        const Property &mp = it.value();
-
+    for (const auto &[name, mp] : std::as_const(properties).asKeyValueRange()) {
         // form is name, typeinfo, flags
-        idata[offset++] = strings.enter(it.key()); // name
+        idata[offset++] = strings.enter(name);
         Q_ASSERT(mp.type != QMetaType::UnknownType);
         idata[offset++] = mp.type;
         idata[offset++] = mp.flags;
diff --git a/src/dbus/qdbusmisc.cpp b/src/dbus/qdbusmisc.cpp
index b1da47111e..502624cd66 100644
--- a/src/dbus/qdbusmisc.cpp
+++ b/src/dbus/qdbusmisc.cpp
@@ -117,10 +117,7 @@ int qDBusParametersForMethod(const QList<QByteArray> &parameterTypes, QList<QMet
     metaTypes.append(QMetaType());        // return type
     int inputCount = 0;
     bool seenMessage = false;
-    QList<QByteArray>::ConstIterator it = parameterTypes.constBegin();
-    QList<QByteArray>::ConstIterator end = parameterTypes.constEnd();
-    for ( ; it != end; ++it) {
-        QByteArray type = *it;
+    for (QByteArray type : parameterTypes) {
         if (type.endsWith('*')) {
             errorMsg = "Pointers are not supported: "_L1 + QLatin1StringView(type);
             return -1;