Fix some Clazy detaching container warnings

(not all are valid, but at worst this flips some more
Q_FOREACH uses to c++11 for loops)

src/app/dwg/qgsdwgimportdialog.cpp

@@ -471,7 +471,7 @@ void QgsDwgImportDialog::on_buttonBox_accepted()
     QgsLayerTreeGroup *dwgGroup = QgisApp::instance()->layerTreeView()->layerTreeModel()->rootGroup()->addGroup( leLayerGroup->text() );
     Q_ASSERT( dwgGroup );
 
-    Q_FOREACH ( QString layer, layers.keys() )
+    Q_FOREACH ( const QString &layer, layers.keys() )
     {
       createGroup( dwgGroup, layer, QStringList( layer ), layers[layer] );
     }

src/app/dwg/qgsdwgimporter.cpp

@@ -2606,7 +2606,7 @@ bool QgsDwgImporter::expandInserts( QString &error )
     QTransform t;
     t.translate( p.x(), p.y() ).scale( xscale, yscale ).rotateRadians( angle );
 
-    Q_FOREACH ( QString name, QStringList() << "hatches" << "lines" << "polylines" << "texts" << "points" )
+    Q_FOREACH ( const QString &name, QStringList() << "hatches" << "lines" << "polylines" << "texts" << "points" )
     {
       OGRLayerH src = OGR_DS_ExecuteSQL( mDs, QString( "SELECT * FROM %1 WHERE block=%2" ).arg( name ).arg( handle ).toUtf8().constData(), nullptr, nullptr );
       if ( !src )

src/app/qgscrashreport.cpp

@@ -108,7 +108,7 @@ const QString QgsCrashReport::toHtml() const
   }
 
   QString report;
-  Q_FOREACH ( QString line, reportData )
+  Q_FOREACH ( const QString &line, reportData )
   {
     report += line + "<br>";
   }

src/app/qgsjoindialog.cpp

@@ -171,7 +171,8 @@ void QgsJoinDialog::joinedLayerChanged( QgsMapLayer *layer )
 
   mUseJoinFieldsSubset->setChecked( false );
   QStandardItemModel *subsetModel = new QStandardItemModel( this );
-  Q_FOREACH ( const QgsField &field, vLayer->fields() )
+  const QgsFields layerFields = vLayer->fields();
+  for ( const QgsField &field : layerFields )
   {
     QStandardItem *subsetItem = new QStandardItem( field.name() );
     subsetItem->setCheckable( true );

src/app/qgsmaplayerstyleguiutils.cpp

@@ -62,7 +62,7 @@ QList<QAction *> QgsMapLayerStyleGuiUtils::actionsUseStyle( QgsMapLayer *layer,
   bool onlyOneStyle = mgr->styles().count() == 1;
 
   QList<QAction *> actions;
-  Q_FOREACH ( QString name, mgr->styles() )
+  Q_FOREACH ( const QString &name, mgr->styles() )
   {
     bool active = name == mgr->currentStyle();
     QAction *actionUse = new QAction( name, parent );

src/core/composer/qgscomposerattributetablev2.cpp

@@ -201,7 +201,8 @@ void QgsComposerAttributeTableV2::resetColumns()
 
   //rebuild columns list from vector layer fields
   int idx = 0;
-  Q_FOREACH ( const QgsField &field, source->fields() )
+  const QgsFields sourceFields = source->fields();
+  for ( const auto &field : sourceFields )
   {
     QString currentAlias = source->attributeDisplayName( idx );
     QgsComposerTableColumn *col = new QgsComposerTableColumn;
@@ -319,7 +320,7 @@ void QgsComposerAttributeTableV2::setDisplayedFields( const QStringList &fields,
   qDeleteAll( mColumns );
   mColumns.clear();
 
-  QgsFields layerFields = source->fields();
+  const QgsFields layerFields = source->fields();
 
   if ( !fields.isEmpty() )
   {
@@ -340,7 +341,7 @@ void QgsComposerAttributeTableV2::setDisplayedFields( const QStringList &fields,
   {
     //resetting, so add all attributes to columns
     int idx = 0;
-    Q_FOREACH ( const QgsField &field, layerFields )
+    for ( const QgsField &field : layerFields )
     {
       QString currentAlias = source->attributeDisplayName( idx );
       QgsComposerTableColumn *col = new QgsComposerTableColumn;

src/core/providers/memory/qgsmemoryproviderutils.cpp

@@ -61,7 +61,7 @@ QgsVectorLayer *QgsMemoryProviderUtils::createMemoryLayer( const QString &name,
   {
     parts << QStringLiteral( "crs=" ) + crs.authid();
   }
-  Q_FOREACH ( const QgsField &field, fields )
+  for ( const auto &field : fields )
   {
     parts << QStringLiteral( "field=%1:%2" ).arg( field.name(), memoryLayerFieldType( field.type() ) );
   }

src/core/qgsattributetableconfig.cpp

@@ -80,7 +80,7 @@ void QgsAttributeTableConfig::update( const QgsFields &fields )
     }
   }
 
-  Q_FOREACH ( const QgsField &field, fields )
+  for ( const auto &field : fields )
   {
     if ( !columns.contains( field.name() ) )
     {

src/core/qgsdataitem.cpp

@@ -1135,10 +1135,8 @@ void QgsZipItem::init()
     // keys << "ogr" << "gdal";
     keys << QStringLiteral( "gdal" ) << QStringLiteral( "ogr" );
 
-    QStringList::const_iterator i;
-    for ( i = keys.begin(); i != keys.end(); ++i )
+    for ( const auto &k : qgsAsConst( keys ) )
     {
-      QString k( *i );
       QgsDebugMsgLevel( "provider " + k, 3 );
       // some providers hangs with empty uri (PostGIS) etc...
       // -> using libraries directly

src/core/qgsgml.cpp

@@ -603,7 +603,7 @@ void QgsGmlStreamingParser::startElement( const XML_Char *el, const XML_Char **a
   {
     QString currentTypename( QString::fromUtf8( pszLocalName, localNameLen ) );
     QMap< QString, LayerProperties >::const_iterator iter = mMapTypeNameToProperties.constFind( currentTypename );
-    if ( iter != mMapTypeNameToProperties.end() )
+    if ( iter != mMapTypeNameToProperties.constEnd() )
     {
       mFeatureTupleDepth = mParseDepth;
       mCurrentTypename = currentTypename;

src/core/qgsjsonutils.cpp

@@ -178,7 +178,7 @@ QString QgsJsonExporter::exportFeature( const QgsFeature &feature, const QVarian
           QgsFeatureIterator it = childLayer->getFeatures( req );
           QVector<QVariant> attributeWidgetCaches;
           int fieldIndex = 0;
-          Q_FOREACH ( const QgsField &field, childLayer->fields() )
+          for ( const auto &field : childLayer->fields() )
           {
             QgsEditorWidgetSetup setup = field.editorWidgetSetup();
             QgsFieldFormatter *fieldFormatter = QgsApplication::fieldFormatterRegistry()->fieldFormatter( setup.type() );

src/core/qgsofflineediting.cpp

@@ -497,7 +497,8 @@ QgsVectorLayer *QgsOfflineEditing::copyVectorLayer( QgsVectorLayer *layer, sqlit
   // create table
   QString sql = QStringLiteral( "CREATE TABLE '%1' (" ).arg( tableName );
   QString delim = QLatin1String( "" );
-  Q_FOREACH ( const QgsField &field, layer->dataProvider()->fields() )
+  const QgsFields providerFields = layer->dataProvider()->fields();
+  for ( const auto &field : providerFields )
   {
     QString dataType = QLatin1String( "" );
     QVariant::Type type = field.type();

src/core/qgsprojectproperty.cpp

@@ -27,22 +27,26 @@ QgsProjectProperty::QgsProjectProperty() //NOLINT
 
 void QgsProjectPropertyValue::dump( int tabs ) const
 {
+  Q_UNUSED( tabs );
+#ifdef QGISDEBUG
+
   QString tabString;
   tabString.fill( '\t', tabs );
 
   if ( QVariant::StringList == mValue.type() )
   {
-    QStringList sl = mValue.toStringList();
+    const QStringList sl = mValue.toStringList();
 
-    for ( QStringList::const_iterator i = sl.begin(); i != sl.end(); ++i )
+    for ( const auto &string : sl )
     {
-      QgsDebugMsg( QString( "%1[%2] " ).arg( tabString, *i ) );
+      QgsDebugMsg( QString( "%1[%2] " ).arg( tabString, string ) );
     }
   }
   else
   {
     QgsDebugMsg( QString( "%1%2" ).arg( tabString, mValue.toString() ) );
   }
+#endif
 }
 
 bool QgsProjectPropertyValue::readXml( const QDomNode &keyNode )

src/core/qgsvectorlayer.cpp

@@ -257,7 +257,7 @@ QgsVectorLayer *QgsVectorLayer::clone() const
     layer->setDefaultValueExpression( i, defaultValueExpression( i ) );
 
     QMap< QgsFieldConstraints::Constraint, QgsFieldConstraints::ConstraintStrength> constraints = fieldConstraintsAndStrength( i );
-    for ( QgsFieldConstraints::Constraint c : constraints.keys() )
+    Q_FOREACH ( QgsFieldConstraints::Constraint c,  constraints.keys() )
     {
       layer->setFieldConstraint( i, c, constraints.value( c ) );
     }

src/core/qgsvectorlayereditbuffer.cpp

@@ -320,7 +320,7 @@ bool QgsVectorLayerEditBuffer::commitChanges( QStringList &commitErrors )
     {
       if ( provider->doesStrictFeatureTypeCheck() )
       {
-        for ( QgsFeature f : mAddedFeatures )
+        for ( const auto &f : qgsAsConst( mAddedFeatures ) )
         {
           if ( ( ! f.hasGeometry() ) ||
                ( f.geometry().wkbType() == provider->wkbType() ) )

src/core/qgsvectorlayerjoinbuffer.cpp

@@ -564,7 +564,8 @@ bool QgsVectorLayerJoinBuffer::addFeatures( QgsFeatureList &features, QgsFeature
           }
           else
           {
-            Q_FOREACH ( const QgsField &field, joinFeature.fields() )
+            const QgsFields joinFields = joinFeature.fields();
+            for ( const auto &field : joinFields )
             {
               QVariant newValue = joinFeature.attribute( field.name() );
               int fieldIndex = joinLayer->fields().indexOf( field.name() );
@@ -576,7 +577,8 @@ bool QgsVectorLayerJoinBuffer::addFeatures( QgsFeatureList &features, QgsFeature
         {
           // joined feature is added only if one of its field is not null
           bool notNullFields = false;
-          Q_FOREACH ( const QgsField &field, joinFeature.fields() )
+          const QgsFields joinFields = joinFeature.fields();
+          for ( const auto &field : joinFields )
           {
             if ( field.name() == info.joinFieldName() )
               continue;

src/core/qgsvectorlayerjoininfo.cpp

@@ -56,7 +56,8 @@ QgsFeature QgsVectorLayerJoinInfo::extractJoinedFeature( const QgsFeature &featu
     joinFeature.setFields( joinLayer()->fields() );
     joinFeature.setAttribute( joinFieldName(), idFieldValue );
 
-    Q_FOREACH ( const QgsField &field, joinFeature.fields() )
+    const QgsFields joinFields = joinFeature.fields();
+    for ( const auto &field : joinFields )
     {
       const QString prefixedName = prefixedFieldName( field );
 

src/core/qgsvirtuallayerdefinitionutils.cpp

@@ -48,7 +48,8 @@ QgsVirtualLayerDefinition QgsVirtualLayerDefinitionUtils::fromJoinedLayer( QgsVe
       def.setUid( uid );
     }
   }
-  Q_FOREACH ( const QgsField &f, layer->dataProvider()->fields() )
+  const QgsFields providerFields = layer->dataProvider()->fields();
+  for ( const auto &f : providerFields )
   {
     columns << "t." + f.name();
   }
@@ -72,7 +73,8 @@ QgsVirtualLayerDefinition QgsVirtualLayerDefinitionUtils::fromJoinedLayer( QgsVe
     }
     else
     {
-      Q_FOREACH ( const QgsField &f, joinedLayer->fields() )
+      const QgsFields joinFields = joinedLayer->fields();
+      for ( const QgsField &f : joinFields )
       {
         if ( f.name() == join.joinFieldName() )
           continue;

src/core/qgsziputils.cpp

@@ -132,7 +132,7 @@ bool QgsZipUtils::zip( const QString &zipFilename, const QStringList &files )
 
   if ( rc == ZIP_ER_OK && z != NULL )
   {
-    Q_FOREACH ( QString file, files )
+    for ( const auto &file : files )
     {
       QFileInfo fileInfo( file );
       if ( !fileInfo.exists() )

src/gui/qgsattributeform.cpp

@@ -2009,7 +2009,8 @@ void QgsAttributeForm::updateJoinedFields( const QgsEditorWidgetWrapper &eww )
     }
     else
     {
-      Q_FOREACH ( const QgsField &field, joinFeature.fields() )
+      const QgsFields joinFields = joinFeature.fields();
+      for ( const QgsField &field : joinFields )
       {
         QString prefixedName = info->prefixedFieldName( field );
         QVariant val;

src/gui/qgsfilewidget.cpp

@@ -80,9 +80,12 @@ QString QgsFileWidget::filePath()
 QStringList QgsFileWidget::splitFilePaths( const QString &path )
 {
   QStringList paths;
-  for ( auto pathsPart : path.split( QRegExp( "\"\\s+\"" ), QString::SkipEmptyParts ) )
+  const QStringList pathParts = path.split( QRegExp( "\"\\s+\"" ), QString::SkipEmptyParts );
+  for ( const auto &pathsPart : pathParts )
   {
-    paths.append( pathsPart.remove( QRegExp( "(^\\s*\")|(\"\\s*)" ) ) );
+    QString cleaned = pathsPart;
+    cleaned.remove( QRegExp( "(^\\s*\")|(\"\\s*)" ) );
+    paths.append( cleaned );
   }
   return paths;
 }

src/gui/qgsmaptoolidentify.cpp

@@ -610,11 +610,12 @@ bool QgsMapToolIdentify::identifyRasterLayer( QList<IdentifyResult> *results, Qg
         }
 
         // list of feature stores for a single sublayer
-        QgsFeatureStoreList featureStoreList = values.value( i ).value<QgsFeatureStoreList>();
+        const QgsFeatureStoreList featureStoreList = values.value( i ).value<QgsFeatureStoreList>();
 
-        Q_FOREACH ( QgsFeatureStore featureStore, featureStoreList )
+        for ( const QgsFeatureStore &featureStore : featureStoreList )
         {
-          Q_FOREACH ( QgsFeature feature, featureStore.features() )
+          const QgsFeatureList storeFeatures = featureStore.features();
+          for ( QgsFeature feature : storeFeatures )
           {
             attributes.clear();
             // WMS sublayer and feature type, a sublayer may contain multiple feature types.

src/gui/qgsoptionsdialogbase.cpp

@@ -232,7 +232,7 @@ void QgsOptionsDialogBase::searchText( const QString &text )
     mOptListWidget->setRowHidden( r, !text.isEmpty() );
   }
 
-  for ( QPair< QgsSearchHighlightOptionWidget *, int > rsw : mRegisteredSearchWidgets )
+  for ( const QPair< QgsSearchHighlightOptionWidget *, int > &rsw : qgsAsConst( mRegisteredSearchWidgets ) )
   {
     rsw.first->reset();
     if ( !text.isEmpty() && rsw.first->searchHighlight( text ) )

src/gui/symbology/qgspointdisplacementrendererwidget.cpp

@@ -72,7 +72,8 @@ QgsPointDisplacementRendererWidget::QgsPointDisplacementRendererWidget( QgsVecto
   //insert attributes into combo box
   if ( layer )
   {
-    Q_FOREACH ( const QgsField &f, layer->fields() )
+    const QgsFields layerFields = layer->fields();
+    for ( const QgsField &f : layerFields )
     {
       mLabelFieldComboBox->addItem( f.name() );
     }

src/providers/grass/qgsgrass.cpp

@@ -2369,7 +2369,7 @@ void QgsGrass::createTable( dbDriver *driver, const QString &tableName, const Qg
   }
 
   QStringList fieldsStringList;
-  Q_FOREACH ( const QgsField &field, fields )
+  for ( const QgsField &field : fields )
   {
     QString name = field.name().toLower().replace( QLatin1String( " " ), QLatin1String( "_" ) );
     if ( name.at( 0 ).isDigit() )

src/providers/grass/qgsgrassvectormaplayer.cpp

@@ -332,10 +332,10 @@ void QgsGrassVectorMapLayer::close()
   }
 }
 
-QStringList QgsGrassVectorMapLayer::fieldNames( QgsFields &fields )
+QStringList QgsGrassVectorMapLayer::fieldNames( const QgsFields &fields )
 {
   QStringList list;
-  Q_FOREACH ( const QgsField &field, fields )
+  for ( const QgsField &field : fields )
   {
     list << field.name();
   }
@@ -598,7 +598,7 @@ void QgsGrassVectorMapLayer::createTable( const QgsFields &fields, QString &erro
 
   QgsFields catFields;
   catFields.append( QgsField( mFieldInfo->key, QVariant::Int, QStringLiteral( "integer" ) ) );
-  Q_FOREACH ( const QgsField &field, fields )
+  for ( const QgsField &field : fields )
   {
     catFields.append( field );
   }
@@ -643,7 +643,7 @@ void QgsGrassVectorMapLayer::createTable( const QgsFields &fields, QString &erro
 
   if ( mFieldInfo )
   {
-    Q_FOREACH ( const QgsField &field, fields )
+    for ( const QgsField &field : fields )
     {
       mTableFields.append( field );
       mAttributeFields.append( field );

src/providers/grass/qgsgrassvectormaplayer.h

@@ -65,7 +65,7 @@ class GRASS_LIB_EXPORT QgsGrassVectorMapLayer : public QObject
      *  This fields are used by layers which are not editied to reflect current state of editing. */
     QgsFields &tableFields() { return mTableFields; }
 
-    static QStringList fieldNames( QgsFields &fields );
+    static QStringList fieldNames( const QgsFields &fields );
 
     QMap<int, QList<QVariant> > &attributes() { return mAttributes; }
 

src/providers/wfs/qgswfsshareddata.cpp

@@ -371,7 +371,7 @@ bool QgsWFSSharedData::createCache()
     {
       mCacheTablename = QStringLiteral( "features" );
       sql = QStringLiteral( "CREATE TABLE %1 (%2 INTEGER PRIMARY KEY" ).arg( mCacheTablename, fidName );
-      Q_FOREACH ( const QgsField &field, cacheFields )
+      for ( const QgsField &field : qgsAsConst( cacheFields ) )
       {
         QString type( QStringLiteral( "VARCHAR" ) );
         if ( field.type() == QVariant::Int )