Pass by const ref where possible

python/core/qgsjsonutils.sip

@@ -248,7 +248,7 @@ class QgsJsonUtils
 %End
 
     static QString exportAttributes( const QgsFeature &feature, QgsVectorLayer *layer = 0,
-                                     QVector<QVariant> attributeWidgetCaches = QVector<QVariant>() );
+                                     const QVector<QVariant> &attributeWidgetCaches = QVector<QVariant>() );
 %Docstring
  Exports all attributes from a QgsFeature as a JSON map type.
  \param feature feature to export

python/core/qgsmaprenderertask.sip

@@ -48,7 +48,7 @@ class QgsMapRendererTask : QgsTask
  Adds ``annotations`` to be rendered on the map.
 %End
 
-    void addDecorations( QList< QgsMapDecoration * > decorations );
+    void addDecorations( const QList<QgsMapDecoration *> &decorations );
 %Docstring
  Adds ``decorations`` to be rendered on the map.
 %End

python/core/qgssettings.sip

@@ -166,7 +166,7 @@ Returns a list of all key top-level groups (same as childGroups) but only for gr
 Return the path to the Global Settings QSettings storage file
  :rtype: str
 %End
-    static bool setGlobalSettingsPath( QString path );
+    static bool setGlobalSettingsPath( const QString &path );
 %Docstring
 Set the Global Settings QSettings storage file
  :rtype: bool

python/gui/qgsfiledownloader.sip

@@ -32,7 +32,7 @@ class QgsFileDownloader : QObject
 %End
   public:
 
-    QgsFileDownloader( const QUrl &url, const QString &outputFileName, bool guiNotificationsEnabled = true, QString authcfg = QString() );
+    QgsFileDownloader( const QUrl &url, const QString &outputFileName, bool guiNotificationsEnabled = true, const QString &authcfg = QString() );
 %Docstring
  QgsFileDownloader
  \param url the download url

src/app/dwg/qgsdwgimportdialog.cpp

@@ -267,7 +267,7 @@ void QgsDwgImportDialog::on_pbImportDrawing_clicked()
   on_pbLoadDatabase_clicked();
 }
 
-QgsVectorLayer *QgsDwgImportDialog::layer( QgsLayerTreeGroup *layerGroup, QString layerFilter, QString table )
+QgsVectorLayer *QgsDwgImportDialog::layer( QgsLayerTreeGroup *layerGroup, const QString &layerFilter, const QString &table )
 {
   QgsVectorLayer *l = new QgsVectorLayer( QString( "%1|layername=%2" ).arg( leDatabase->text(), table ), table, "ogr", false );
   l->setSubsetString( QString( "%1space=0 AND block=-1" ).arg( layerFilter ) );
@@ -283,7 +283,7 @@ QgsVectorLayer *QgsDwgImportDialog::layer( QgsLayerTreeGroup *layerGroup, QStrin
   return l;
 }
 
-void QgsDwgImportDialog::createGroup( QgsLayerTreeGroup *group, QString name, QStringList layers, bool visible )
+void QgsDwgImportDialog::createGroup( QgsLayerTreeGroup *group, const QString &name, const QStringList &layers, bool visible )
 {
   QgsLayerTreeGroup *layerGroup = group->addGroup( name );
   QgsDebugMsg( QString( " %1" ).arg( name ) ) ;

src/app/dwg/qgsdwgimportdialog.h

@@ -44,8 +44,8 @@ class QgsDwgImportDialog : public QDialog, private Ui::QgsDwgImportBase
     void showHelp();
 
   private:
-    QgsVectorLayer *layer( QgsLayerTreeGroup *layerGroup, QString layer, QString table );
+    QgsVectorLayer *layer( QgsLayerTreeGroup *layerGroup, const QString &layer, const QString &table );
-    void createGroup( QgsLayerTreeGroup *group, QString name, QStringList layers, bool visible );
+    void createGroup( QgsLayerTreeGroup *group, const QString &name, const QStringList &layers, bool visible );
     void updateUI();
     void expandInserts();
     void updateCheckState( Qt::CheckState state );

src/app/dwg/qgsdwgimporter.cpp

@@ -75,7 +75,7 @@ QgsDwgImporter::QgsDwgImporter( const QString &database, const QgsCoordinateRefe
   QgsDebugMsg( QString( "CRS %1[%2]: %3" ).arg( mCrs ).arg( ( qint64 ) mCrsH, 0, 16 ).arg( crswkt ) );
 }
 
-bool QgsDwgImporter::exec( QString sql, bool logError )
+bool QgsDwgImporter::exec( const QString &sql, bool logError )
 {
   if ( !mDs )
   {
@@ -104,7 +104,7 @@ bool QgsDwgImporter::exec( QString sql, bool logError )
   return false;
 }
 
-OGRLayerH QgsDwgImporter::query( QString sql )
+OGRLayerH QgsDwgImporter::query( const QString &sql )
 {
   if ( !mDs )
   {
@@ -259,7 +259,7 @@ bool QgsDwgImporter::import( const QString &drawing, QString &error, bool doExpa
 
   struct field
   {
-    field( QString name, OGRFieldType ogrType, int width = -1, int precision = -1 )
+    field( const QString &name, OGRFieldType ogrType, int width = -1, int precision = -1 )
       : mName( name ), mOgrType( ogrType ), mWidth( width ), mPrecision( precision )
     {}
 
@@ -271,7 +271,7 @@ bool QgsDwgImporter::import( const QString &drawing, QString &error, bool doExpa
 
   struct table
   {
-    table( QString name, QString desc, OGRwkbGeometryType wkbType, QList<field> fields )
+    table( const QString &name, const QString &desc, OGRwkbGeometryType wkbType, const QList<field> &fields )
       : mName( name ), mDescription( desc ), mWkbType( wkbType ), mFields( fields )
     {}
 
@@ -931,7 +931,7 @@ void QgsDwgImporter::addLayer( const DRW_Layer &data )
   OGR_F_Destroy( f );
 }
 
-void QgsDwgImporter::setString( OGRFeatureDefnH dfn, OGRFeatureH f, QString field, const std::string &value ) const
+void QgsDwgImporter::setString( OGRFeatureDefnH dfn, OGRFeatureH f, const QString &field, const std::string &value ) const
 {
   int idx = OGR_FD_GetFieldIndex( dfn, field.toLower().toUtf8().constData() );
   if ( idx < 0 )
@@ -942,7 +942,7 @@ void QgsDwgImporter::setString( OGRFeatureDefnH dfn, OGRFeatureH f, QString fiel
   OGR_F_SetFieldString( f, idx, value.c_str() );
 }
 
-void QgsDwgImporter::setDouble( OGRFeatureDefnH dfn, OGRFeatureH f, QString field, double value ) const
+void QgsDwgImporter::setDouble( OGRFeatureDefnH dfn, OGRFeatureH f, const QString &field, double value ) const
 {
   int idx = OGR_FD_GetFieldIndex( dfn, field.toLower().toUtf8().constData() );
   if ( idx < 0 )
@@ -953,7 +953,7 @@ void QgsDwgImporter::setDouble( OGRFeatureDefnH dfn, OGRFeatureH f, QString fiel
   OGR_F_SetFieldDouble( f, idx, value );
 }
 
-void QgsDwgImporter::setInteger( OGRFeatureDefnH dfn, OGRFeatureH f, QString field, int value ) const
+void QgsDwgImporter::setInteger( OGRFeatureDefnH dfn, OGRFeatureH f, const QString &field, int value ) const
 {
   int idx = OGR_FD_GetFieldIndex( dfn, field.toLower().toUtf8().constData() );
   if ( idx < 0 )
@@ -964,7 +964,7 @@ void QgsDwgImporter::setInteger( OGRFeatureDefnH dfn, OGRFeatureH f, QString fie
   OGR_F_SetFieldInteger( f, idx, value );
 }
 
-void QgsDwgImporter::setPoint( OGRFeatureDefnH dfn, OGRFeatureH f, QString field, const DRW_Coord &p ) const
+void QgsDwgImporter::setPoint( OGRFeatureDefnH dfn, OGRFeatureH f, const QString &field, const DRW_Coord &p ) const
 {
   QVector<double> ext( 3 );
   ext[0] = p.x;

src/app/dwg/qgsdwgimporter.h

@@ -168,17 +168,17 @@ class QgsDwgImporter : public DRW_Interface
   private:
     void startTransaction();
     void commitTransaction();
-    bool exec( QString sql, bool logError = true );
+    bool exec( const QString &sql, bool logError = true );
-    OGRLayerH query( QString sql );
+    OGRLayerH query( const QString &sql );
 
     void addEntity( OGRFeatureDefnH dfn, OGRFeatureH f, const DRW_Entity &data );
     QString colorString( int color, int color24, int transparency, const std::string &layer ) const;
     double lineWidth( int lWeight, const std::string &layer ) const;
     QString linetypeString( const std::string &linetype, const std::string &layer ) const;
-    void setString( OGRFeatureDefnH dfn, OGRFeatureH f, QString field, const std::string &value ) const;
+    void setString( OGRFeatureDefnH dfn, OGRFeatureH f, const QString &field, const std::string &value ) const;
-    void setDouble( OGRFeatureDefnH dfn, OGRFeatureH f, QString field, double value ) const;
+    void setDouble( OGRFeatureDefnH dfn, OGRFeatureH f, const QString &field, double value ) const;
-    void setInteger( OGRFeatureDefnH dfn, OGRFeatureH f, QString field, int value ) const;
+    void setInteger( OGRFeatureDefnH dfn, OGRFeatureH f, const QString &field, int value ) const;
-    void setPoint( OGRFeatureDefnH dfn, OGRFeatureH f, QString field, const DRW_Coord &value ) const;
+    void setPoint( OGRFeatureDefnH dfn, OGRFeatureH f, const QString &field, const DRW_Coord &value ) const;
 
     bool curveFromLWPolyline( const DRW_LWPolyline &data, QgsCompoundCurve &cc );
 

src/app/nodetool/qgsnodetool.cpp

@@ -1784,7 +1784,7 @@ void QgsNodeTool::CircularBand::updateRubberBand( const QgsPointXY &mapPoint )
 }
 
 
-void QgsNodeTool::validationErrorFound( QgsGeometry::Error e )
+void QgsNodeTool::validationErrorFound( const QgsGeometry::Error &e )
 {
   QgsGeometryValidator *validator = qobject_cast<QgsGeometryValidator *>( sender() );
   if ( !validator )

src/app/nodetool/qgsnodetool.h

@@ -90,7 +90,7 @@ class APP_EXPORT QgsNodeTool : public QgsMapToolAdvancedDigitizing
 
     void deleteNodeEditorSelection();
 
-    void validationErrorFound( QgsGeometry::Error e );
+    void validationErrorFound( const QgsGeometry::Error &e );
 
     void validationFinished();
 

src/app/qgisapp.cpp

@@ -603,7 +603,7 @@ static bool cmpByText_( QAction *a, QAction *b )
 QgisApp *QgisApp::sInstance = nullptr;
 
 // constructor starts here
-QgisApp::QgisApp( QSplashScreen *splash, bool restorePlugins, bool skipVersionCheck, const QString rootProfileLocation, const QString activeProfile, QWidget *parent, Qt::WindowFlags fl )
+QgisApp::QgisApp( QSplashScreen *splash, bool restorePlugins, bool skipVersionCheck, const QString &rootProfileLocation, const QString &activeProfile, QWidget *parent, Qt::WindowFlags fl )
   : QMainWindow( parent, fl )
   , mSplash( splash )
   , mShowProjectionTab( false )
@@ -1505,7 +1505,7 @@ bool QgisApp::event( QEvent *event )
   return done;
 }
 
-void QgisApp::dataSourceManager( QString pageName )
+void QgisApp::dataSourceManager( const QString &pageName )
 {
   if ( ! mDataSourceManagerDialog )
   {
@@ -11768,7 +11768,7 @@ void QgisApp::endProfile()
   QgsApplication::profiler()->end();
 }
 
-void QgisApp::functionProfile( void ( QgisApp::*fnc )(), QgisApp *instance, QString name )
+void QgisApp::functionProfile( void ( QgisApp::*fnc )(), QgisApp *instance, const QString &name )
 {
   startProfile( name );
   ( instance->*fnc )();
@@ -12484,7 +12484,7 @@ QMenu *QgisApp::createPopupMenu()
 }
 
 
-void QgisApp::showSystemNotification( const QString title, const QString message )
+void QgisApp::showSystemNotification( const QString &title, const QString &message )
 {
   // Menubar icon is hidden by default. Show to enable notification bubbles
   mTray->show();

src/app/qgisapp.h

@@ -165,8 +165,8 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
   public:
     //! Constructor
     QgisApp( QSplashScreen *splash, bool restorePlugins = true,
-             bool skipVersionCheck = false, const QString rootProfileLocation = QString(),
+             bool skipVersionCheck = false, const QString &rootProfileLocation = QString(),
-             const QString activeProfile = QString(),
+             const QString &activeProfile = QString(),
              QWidget *parent = nullptr, Qt::WindowFlags fl = Qt::Window );
     //! Constructor for unit tests
     QgisApp();
@@ -377,7 +377,7 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
      * \param title
      * \param message
      */
-    void showSystemNotification( const QString title, const QString message );
+    void showSystemNotification( const QString &title, const QString &message );
 
 
     //! Actions to be inserted in menus and toolbars
@@ -793,7 +793,7 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
      * \param pageName the page name, usually the provider name or "browser" (for the browser panel)
      *        or "ogr" (vector layers) or "raster" (raster layers)
      */
-    void dataSourceManager( QString pageName = QString() );
+    void dataSourceManager( const QString &pageName = QString() );
 
     /** Add a raster layer directly without prompting user for location
       The caller must provide information compatible with the provider plugin
@@ -1599,7 +1599,7 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
   private:
     void startProfile( const QString &name );
     void endProfile();
-    void functionProfile( void ( QgisApp::*fnc )(), QgisApp *instance, QString name );
+    void functionProfile( void ( QgisApp::*fnc )(), QgisApp *instance, const QString &name );
 
     /** This method will open a dialog so the user can select GDAL sublayers to load
      * \returns true if any items were loaded

src/app/qgsattributeactionpropertiesdialog.cpp

@@ -31,7 +31,7 @@
 #include <QFileDialog>
 #include <QImageWriter>
 
-QgsAttributeActionPropertiesDialog::QgsAttributeActionPropertiesDialog( QgsAction::ActionType type, const QString &description, const QString &shortTitle, const QString &iconPath, const QString &actionText, bool capture, QSet<QString> actionScopes, QgsVectorLayer *layer, QWidget *parent )
+QgsAttributeActionPropertiesDialog::QgsAttributeActionPropertiesDialog( QgsAction::ActionType type, const QString &description, const QString &shortTitle, const QString &iconPath, const QString &actionText, bool capture, const QSet<QString> &actionScopes, QgsVectorLayer *layer, QWidget *parent )
   : QDialog( parent )
   , mLayer( layer )
 {

src/app/qgsattributeactionpropertiesdialog.h

@@ -28,7 +28,7 @@ class QgsAttributeActionPropertiesDialog: public QDialog, private Ui::QgsAttribu
     Q_OBJECT
 
   public:
-    QgsAttributeActionPropertiesDialog( QgsAction::ActionType type, const QString &description, const QString &shortTitle, const QString &iconPath, const QString &actionText, bool capture, QSet<QString> actionScopes, QgsVectorLayer *layer, QWidget *parent = nullptr );
+    QgsAttributeActionPropertiesDialog( QgsAction::ActionType type, const QString &description, const QString &shortTitle, const QString &iconPath, const QString &actionText, bool capture, const QSet<QString> &actionScopes, QgsVectorLayer *layer, QWidget *parent = nullptr );
 
     QgsAttributeActionPropertiesDialog( QgsVectorLayer *layer, QWidget *parent = nullptr );
 

src/app/qgsmapsavedialog.cpp

@@ -40,7 +40,7 @@
 
 Q_GUI_EXPORT extern int qt_defaultDpiX();
 
-QgsMapSaveDialog::QgsMapSaveDialog( QWidget *parent, QgsMapCanvas *mapCanvas, QList< QgsDecorationItem * > decorations, QList< QgsAnnotation *> annotations, DialogType type )
+QgsMapSaveDialog::QgsMapSaveDialog( QWidget *parent, QgsMapCanvas *mapCanvas, const QList<QgsDecorationItem *> &decorations, const QList< QgsAnnotation *> &annotations, DialogType type )
   : QDialog( parent )
   , mDialogType( type )
   , mMapCanvas( mapCanvas )

src/app/qgsmapsavedialog.h

@@ -48,8 +48,8 @@ class APP_EXPORT QgsMapSaveDialog: public QDialog, private Ui::QgsMapSaveDialog
     /** Constructor for QgsMapSaveDialog
      */
     QgsMapSaveDialog( QWidget *parent = nullptr, QgsMapCanvas *mapCanvas = nullptr,
-                      QList< QgsDecorationItem * > decorations = QList< QgsDecorationItem * >(),
+                      const QList< QgsDecorationItem * > &decorations = QList< QgsDecorationItem * >(),
-                      QList< QgsAnnotation *> annotations = QList< QgsAnnotation * >(),
+                      const QList<QgsAnnotation *> &annotations = QList< QgsAnnotation * >(),
                       DialogType type = Image );
 
     //! returns extent rectangle

src/core/expression/qgsexpressionfunction.cpp

@@ -131,8 +131,8 @@ QgsStaticExpressionFunction::QgsStaticExpressionFunction( const QString &fnname,
     FcnEval fcn,
     const QString &group,
     const QString &helpText,
-    std::function < bool ( const QgsExpressionNodeFunction *node ) > usesGeometry,
+    const std::function < bool ( const QgsExpressionNodeFunction *node ) > &usesGeometry,
-    std::function < QSet<QString>( const QgsExpressionNodeFunction *node ) > referencedColumns,
+    const std::function < QSet<QString>( const QgsExpressionNodeFunction *node ) > &referencedColumns,
     bool lazyEval,
     const QStringList &aliases,
     bool handlesNull )
@@ -182,7 +182,7 @@ bool QgsStaticExpressionFunction::prepare( const QgsExpressionNodeFunction *node
   return true;
 }
 
-void QgsStaticExpressionFunction::setIsStaticFunction( std::function<bool ( const QgsExpressionNodeFunction *, QgsExpression *, const QgsExpressionContext * )> isStatic )
+void QgsStaticExpressionFunction::setIsStaticFunction( const std::function<bool ( const QgsExpressionNodeFunction *, QgsExpression *, const QgsExpressionContext * )> &isStatic )
 {
   mIsStaticFunc = isStatic;
 }
@@ -193,7 +193,7 @@ void QgsStaticExpressionFunction::setIsStatic( bool isStatic )
   mIsStatic = isStatic;
 }
 
-void QgsStaticExpressionFunction::setPrepareFunction( std::function<bool ( const QgsExpressionNodeFunction *, QgsExpression *, const QgsExpressionContext * )> prepareFunc )
+void QgsStaticExpressionFunction::setPrepareFunction( const std::function<bool ( const QgsExpressionNodeFunction *, QgsExpression *, const QgsExpressionContext * )> &prepareFunc )
 {
   mPrepareFunc = prepareFunc;
 }

src/core/expression/qgsexpressionfunction.h

@@ -369,8 +369,8 @@ class QgsStaticExpressionFunction : public QgsExpressionFunction
                                  FcnEval fcn,
                                  const QString &group,
                                  const QString &helpText,
-                                 std::function < bool ( const QgsExpressionNodeFunction *node ) > usesGeometry,
+                                 const std::function< bool( const QgsExpressionNodeFunction * )> &usesGeometry,
-                                 std::function < QSet<QString>( const QgsExpressionNodeFunction *node ) > referencedColumns,
+                                 const std::function< QSet<QString>( const QgsExpressionNodeFunction * )> &referencedColumns,
                                  bool lazyEval = false,
                                  const QStringList &aliases = QStringList(),
                                  bool handlesNull = false );
@@ -423,7 +423,7 @@ class QgsStaticExpressionFunction : public QgsExpressionFunction
      * By default this is set to a function that checks all arguments that have been passed to the variable
      * and if all of them are static, it will be assumed that the function is static as well.
      */
-    void setIsStaticFunction( std::function < bool( const QgsExpressionNodeFunction *node, QgsExpression *parent, const QgsExpressionContext *context ) > isStatic );
+    void setIsStaticFunction( const std::function< bool ( const QgsExpressionNodeFunction *, QgsExpression *, const QgsExpressionContext * ) > &isStatic );
 
     /**
      * Tag this function as either static or not static.
@@ -440,7 +440,7 @@ class QgsStaticExpressionFunction : public QgsExpressionFunction
      * By default this is set to a function that checks all arguments that have been passed to the variable
      * and if all of them are static, it will be assumed that the function is static as well.
      */
-    void setPrepareFunction( std::function < bool( const QgsExpressionNodeFunction *node, QgsExpression *parent, const QgsExpressionContext *context ) > prepareFunc );
+    void setPrepareFunction( const std::function< bool( const QgsExpressionNodeFunction *, QgsExpression *, const QgsExpressionContext * )> &prepareFunc );
 
     static const QList<QgsExpressionFunction *> &functions();
 

src/core/geometry/qgsgeometryeditutils.cpp

@@ -223,7 +223,7 @@ bool QgsGeometryEditUtils::deletePart( QgsAbstractGeometry *geom, int partNum )
 
 std::unique_ptr<QgsAbstractGeometry> QgsGeometryEditUtils::avoidIntersections( const QgsAbstractGeometry &geom,
     const QList<QgsVectorLayer *> &avoidIntersectionsLayers,
-    QHash<QgsVectorLayer *, QSet<QgsFeatureId> > ignoreFeatures )
+    const QHash<QgsVectorLayer *, QSet<QgsFeatureId> > &ignoreFeatures )
 {
   std::unique_ptr<QgsGeometryEngine> geomEngine( QgsGeometry::createGeometryEngine( &geom ) );
   if ( !geomEngine )

src/core/geometry/qgsgeometryeditutils.h

@@ -72,7 +72,7 @@ class QgsGeometryEditUtils
      */
     static std::unique_ptr< QgsAbstractGeometry > avoidIntersections( const QgsAbstractGeometry &geom,
         const QList<QgsVectorLayer *> &avoidIntersectionsLayers,
-        QHash<QgsVectorLayer *, QSet<QgsFeatureId> > ignoreFeatures = ( QHash<QgsVectorLayer *, QSet<QgsFeatureId> >() ) );
+        const QHash<QgsVectorLayer *, QSet<QgsFeatureId> > &ignoreFeatures = ( QHash<QgsVectorLayer *, QSet<QgsFeatureId> >() ) );
 };
 
 #endif // QGSGEOMETRYEDITUTILS_H

src/core/processing/qgsnativealgorithms.cpp

@@ -249,7 +249,7 @@ QgsDissolveAlgorithm *QgsDissolveAlgorithm::createInstance() const
 }
 
 QVariantMap QgsCollectorAlgorithm::processCollection( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback,
-    std::function<QgsGeometry( const QList< QgsGeometry >& )> collector, int maxQueueLength )
+    const std::function<QgsGeometry( const QList< QgsGeometry >& )> &collector, int maxQueueLength )
 {
   std::unique_ptr< QgsFeatureSource > source( parameterAsSource( parameters, QStringLiteral( "INPUT" ), context ) );
   if ( !source )
@@ -1399,7 +1399,7 @@ QVariantMap QgsSelectByLocationAlgorithm::processAlgorithm( const QVariantMap &p
 void QgsLocationBasedAlgorithm::process( QgsFeatureSource *targetSource,
     QgsFeatureSource *intersectSource,
     const QList< int > &selectedPredicates,
-    std::function < void( const QgsFeature & ) > handleFeatureFunction,
+    const std::function < void( const QgsFeature & ) > &handleFeatureFunction,
     bool onlyRequireTargetIds,
     QgsFeedback *feedback )
 {

src/core/processing/qgsnativealgorithms.h

@@ -139,7 +139,7 @@ class QgsCollectorAlgorithm : public QgsProcessingAlgorithm
   protected:
 
     QVariantMap processCollection( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback,
-                                   std::function<QgsGeometry( const QList< QgsGeometry >& )> collector, int maxQueueLength = 0 );
+                                   const std::function<QgsGeometry( const QList<QgsGeometry>& )> &collector, int maxQueueLength = 0 );
 };
 
 /**
@@ -505,7 +505,7 @@ class QgsLocationBasedAlgorithm : public QgsProcessingAlgorithm
 
     Predicate reversePredicate( Predicate predicate ) const;
     QStringList predicateOptionsList() const;
-    void process( QgsFeatureSource *targetSource, QgsFeatureSource *intersectSource, const QList<int> &selectedPredicates, std::function<void ( const QgsFeature & )> handleFeatureFunction, bool onlyRequireTargetIds, QgsFeedback *feedback );
+    void process( QgsFeatureSource *targetSource, QgsFeatureSource *intersectSource, const QList<int> &selectedPredicates, const std::function< void( const QgsFeature & )> &handleFeatureFunction, bool onlyRequireTargetIds, QgsFeedback *feedback );
 };
 
 /**

src/core/qgsfeaturerequest.cpp

@@ -114,7 +114,7 @@ QgsFeatureRequest &QgsFeatureRequest::setInvalidGeometryCheck( QgsFeatureRequest
   return *this;
 }
 
-QgsFeatureRequest &QgsFeatureRequest::setInvalidGeometryCallback( std::function<void ( const QgsFeature & )> callback )
+QgsFeatureRequest &QgsFeatureRequest::setInvalidGeometryCallback( const std::function<void ( const QgsFeature & )> &callback )
 {
   mInvalidGeometryCallback = callback;
   return *this;
@@ -248,7 +248,7 @@ QgsFeatureRequest &QgsFeatureRequest::setDestinationCrs( const QgsCoordinateRefe
   return *this;
 }
 
-QgsFeatureRequest &QgsFeatureRequest::setTransformErrorCallback( std::function<void ( const QgsFeature & )> callback )
+QgsFeatureRequest &QgsFeatureRequest::setTransformErrorCallback( const std::function<void ( const QgsFeature & )> &callback )
 {
   mTransformErrorCallback = callback;
   return *this;

src/core/qgsfeaturerequest.h

@@ -352,7 +352,7 @@ class CORE_EXPORT QgsFeatureRequest
      * \see invalidGeometryCallback()
      */
 #ifndef SIP_RUN
-    QgsFeatureRequest &setInvalidGeometryCallback( std::function< void( const QgsFeature & ) > callback );
+    QgsFeatureRequest &setInvalidGeometryCallback( const std::function< void( const QgsFeature & )> &callback );
 #else
     QgsFeatureRequest &setInvalidGeometryCallback( SIP_PYCALLABLE / AllowNone / );
     % MethodCode
@@ -545,7 +545,7 @@ class CORE_EXPORT QgsFeatureRequest
      * \see setDestinationCrs()
      */
 #ifndef SIP_RUN
-    QgsFeatureRequest &setTransformErrorCallback( std::function< void( const QgsFeature & ) > callback );
+    QgsFeatureRequest &setTransformErrorCallback( const std::function< void( const QgsFeature & )> &callback );
 #else
     QgsFeatureRequest &setTransformErrorCallback( SIP_PYCALLABLE / AllowNone / );
     % MethodCode

src/core/qgsjsonutils.cpp

@@ -287,7 +287,7 @@ QString QgsJsonUtils::encodeValue( const QVariant &value )
   }
 }
 
-QString QgsJsonUtils::exportAttributes( const QgsFeature &feature, QgsVectorLayer *layer, QVector<QVariant> attributeWidgetCaches )
+QString QgsJsonUtils::exportAttributes( const QgsFeature &feature, QgsVectorLayer *layer, const QVector<QVariant> &attributeWidgetCaches )
 {
   QgsFields fields = feature.fields();
   QString attrs;

src/core/qgsjsonutils.h

@@ -246,7 +246,7 @@ class CORE_EXPORT QgsJsonUtils
      * to speed up exporting the attributes for multiple features from the same layer.
      */
     static QString exportAttributes( const QgsFeature &feature, QgsVectorLayer *layer = nullptr,
-                                     QVector<QVariant> attributeWidgetCaches = QVector<QVariant>() );
+                                     const QVector<QVariant> &attributeWidgetCaches = QVector<QVariant>() );
 
     /** Parse a simple array (depth=1).
      * \param json the JSON to parse

src/core/qgsmaprenderertask.cpp

@@ -51,7 +51,7 @@ void QgsMapRendererTask::addAnnotations( QList< QgsAnnotation * > annotations )
   }
 }
 
-void QgsMapRendererTask::addDecorations( QList< QgsMapDecoration * > decorations )
+void QgsMapRendererTask::addDecorations( const QList< QgsMapDecoration * > &decorations )
 {
   mDecorations = decorations;
 }

src/core/qgsmaprenderertask.h

@@ -72,7 +72,7 @@ class CORE_EXPORT QgsMapRendererTask : public QgsTask
     /**
      * Adds \a decorations to be rendered on the map.
      */
-    void addDecorations( QList< QgsMapDecoration * > decorations );
+    void addDecorations( const QList<QgsMapDecoration *> &decorations );
 
     /**
      * Sets whether a world file will be created alongside an image file.

src/core/qgsprovidermetadata.cpp

@@ -28,7 +28,7 @@ QgsProviderMetadata::QgsProviderMetadata( QString const &_key,
   , library_( _library )
 {}
 
-QgsProviderMetadata::QgsProviderMetadata( const QString &key, const QString &description, QgsProviderMetadata::CreateDataProviderFunction createFunc )
+QgsProviderMetadata::QgsProviderMetadata( const QString &key, const QString &description, const CreateDataProviderFunction &createFunc )
   : key_( key )
   , description_( description )
   , mCreateFunc( createFunc )

src/core/qgsprovidermetadata.h

@@ -61,7 +61,7 @@ class CORE_EXPORT QgsProviderMetadata
      * \since QGIS 3.0
      * \note not available in Python bindings
      */
-    SIP_SKIP QgsProviderMetadata( const QString &key, const QString &description, QgsProviderMetadata::CreateDataProviderFunction createFunc );
+    SIP_SKIP QgsProviderMetadata( const QString &key, const QString &description, const QgsProviderMetadata::CreateDataProviderFunction &createFunc );
 
     /** This returns the unique key associated with the provider
 

src/core/qgssettings.cpp

@@ -24,7 +24,7 @@
 
 QString QgsSettings::sGlobalSettingsPath = QString();
 
-bool QgsSettings::setGlobalSettingsPath( QString path )
+bool QgsSettings::setGlobalSettingsPath( const QString &path )
 {
   if ( QFileInfo::exists( path ) )
   {
@@ -279,7 +279,7 @@ void QgsSettings::setValue( const QString &key, const QVariant &value, const Qgs
 }
 
 // To lower case and clean the path
-QString QgsSettings::sanitizeKey( QString key ) const
+QString QgsSettings::sanitizeKey( const QString &key ) const
 {
   return QDir::cleanPath( key );
 }

src/core/qgssettings.h

@@ -155,7 +155,7 @@ class CORE_EXPORT QgsSettings : public QObject
     //! Return the path to the Global Settings QSettings storage file
     static QString globalSettingsPath() { return sGlobalSettingsPath; }
     //! Set the Global Settings QSettings storage file
-    static bool setGlobalSettingsPath( QString path );
+    static bool setGlobalSettingsPath( const QString &path );
     //! Adds prefix to the current group and starts reading from an array. Returns the size of the array.
     int beginReadArray( const QString &prefix );
 
@@ -229,7 +229,7 @@ class CORE_EXPORT QgsSettings : public QObject
 
     static QString sGlobalSettingsPath;
     void init();
-    QString sanitizeKey( QString key ) const;
+    QString sanitizeKey( const QString &key ) const;
     QSettings *mUserSettings = nullptr;
     QSettings *mGlobalSettings = nullptr;
     bool mUsingGlobalArray = false;

src/gui/qgsdatasourcemanagerdialog.cpp

@@ -78,7 +78,7 @@ QgsDataSourceManagerDialog::~QgsDataSourceManagerDialog()
   delete ui;
 }
 
-void QgsDataSourceManagerDialog::openPage( QString pageName )
+void QgsDataSourceManagerDialog::openPage( const QString &pageName )
 {
   int pageIdx = mPageNames.indexOf( pageName );
   if ( pageIdx != -1 )
@@ -122,7 +122,7 @@ void QgsDataSourceManagerDialog::vectorLayersAdded( const QStringList &layerQStr
 }
 
 
-void QgsDataSourceManagerDialog::addProviderDialog( QgsAbstractDataSourceWidget *dlg, const QString &providerKey, const QString &providerName, const QIcon &icon, QString toolTip )
+void QgsDataSourceManagerDialog::addProviderDialog( QgsAbstractDataSourceWidget *dlg, const QString &providerKey, const QString &providerName, const QIcon &icon, const QString &toolTip )
 {
   mPageNames.append( providerKey );
   ui->mOptionsStackedWidget->addWidget( dlg );

src/gui/qgsdatasourcemanagerdialog.h

@@ -60,7 +60,7 @@ class GUI_EXPORT QgsDataSourceManagerDialog : public QgsOptionsDialogBase, priva
      * \param pageName the page name, usually the provider name or "browser" (for the browser panel)
      *        or "ogr" (vector layers) or "raster" (raster layers)
      */
-    void openPage( QString pageName );
+    void openPage( const QString &pageName );
 
   public slots:
 
@@ -114,7 +114,7 @@ class GUI_EXPORT QgsDataSourceManagerDialog : public QgsOptionsDialogBase, priva
     void providerDialogsRefreshRequested();
 
   private:
-    void addProviderDialog( QgsAbstractDataSourceWidget *dlg, const QString &providerKey, const QString &providerName, const QIcon &icon, QString toolTip = QString() );
+    void addProviderDialog( QgsAbstractDataSourceWidget *dlg, const QString &providerKey, const QString &providerName, const QIcon &icon, const QString &toolTip = QString() );
     void makeConnections( QgsAbstractDataSourceWidget *dlg, const QString &providerKey );
     Ui::QgsDataSourceManagerDialog *ui;
     QgsBrowserDockWidget *mBrowserWidget = nullptr;

src/gui/qgsfiledownloader.cpp

@@ -26,7 +26,7 @@
 #include <QSslError>
 #endif
 
-QgsFileDownloader::QgsFileDownloader( const QUrl &url, const QString &outputFileName, bool enableGuiNotifications, QString authcfg )
+QgsFileDownloader::QgsFileDownloader( const QUrl &url, const QString &outputFileName, bool enableGuiNotifications, const QString &authcfg )
   : mUrl( url )
   , mDownloadCanceled( false )
   , mGuiNotificationsEnabled( enableGuiNotifications )

src/gui/qgsfiledownloader.h

@@ -53,7 +53,7 @@ class GUI_EXPORT QgsFileDownloader : public QObject
      * \param guiNotificationsEnabled if false, the downloader will not display any progress bar or error message
      * \param authcfg optionally apply this authentication configuration
      */
-    QgsFileDownloader( const QUrl &url, const QString &outputFileName, bool guiNotificationsEnabled = true, QString authcfg = QString() );
+    QgsFileDownloader( const QUrl &url, const QString &outputFileName, bool guiNotificationsEnabled = true, const QString &authcfg = QString() );
 
   signals:
     //! Emitted when the download has completed successfully

src/providers/gdal/qgsgdaldataitems.cpp

@@ -24,7 +24,7 @@ void buildSupportedRasterFileFilterAndExtensions( QString &fileFiltersString, QS
 
 
 QgsGdalLayerItem::QgsGdalLayerItem( QgsDataItem *parent,
-                                    QString name, QString path, QString uri,
+                                    const QString &name, const QString &path, const QString &uri,
                                     QStringList *sublayers )
   : QgsLayerItem( parent, name, path, uri, QgsLayerItem::Raster, QStringLiteral( "gdal" ) )
 {

src/providers/gdal/qgsgdaldataitems.h

@@ -27,7 +27,7 @@ class QgsGdalLayerItem : public QgsLayerItem
 
   public:
     QgsGdalLayerItem( QgsDataItem *parent,
-                      QString name, QString path, QString uri,
+                      const QString &name, const QString &path, const QString &uri,
                       QStringList *mSublayers = nullptr );
 
     bool setCrs( const QgsCoordinateReferenceSystem &crs ) override;

src/providers/gdal/qgsgdalprovider.cpp

@@ -103,7 +103,7 @@ int CPL_STDCALL progressCallback( double dfComplete,
   return true;
 }
 
-QgsGdalProvider::QgsGdalProvider( const QString &uri, QgsError error )
+QgsGdalProvider::QgsGdalProvider( const QString &uri, const QgsError &error )
   : QgsRasterDataProvider( uri )
   , mUpdate( false )
   , mValid( false )

src/providers/gdal/qgsgdalprovider.h

@@ -69,7 +69,7 @@ class QgsGdalProvider : public QgsRasterDataProvider, QgsGdalProviderBase
     QgsGdalProvider( QString const &uri = QString(), bool update = false );
 
     //! Create invalid provider with error
-    QgsGdalProvider( QString const &uri, QgsError error );
+    QgsGdalProvider( QString const &uri, const QgsError &error );
 
 
     ~QgsGdalProvider();

src/providers/ogr/qgsgeopackagedataitems.cpp

@@ -46,7 +46,7 @@ QgsDataItem *QgsGeoPackageDataItemProvider::createDataItem( const QString &path,
   return nullptr;
 }
 
-QgsGeoPackageRootItem::QgsGeoPackageRootItem( QgsDataItem *parent, QString name, QString path )
+QgsGeoPackageRootItem::QgsGeoPackageRootItem( QgsDataItem *parent, const QString &name, const QString &path )
   : QgsDataCollectionItem( parent, name, path )
 {
   mCapabilities |= Fast;
@@ -120,7 +120,7 @@ void QgsGeoPackageRootItem::createDatabase()
 #endif
 
 
-QgsGeoPackageConnectionItem::QgsGeoPackageConnectionItem( QgsDataItem *parent, QString name, QString path )
+QgsGeoPackageConnectionItem::QgsGeoPackageConnectionItem( QgsDataItem *parent, const QString &name, const QString &path )
   : QgsDataCollectionItem( parent, name, path )
   , mPath( path )
 {
@@ -328,7 +328,7 @@ bool QgsGeoPackageConnectionItem::handleDrop( const QMimeData *data, Qt::DropAct
 }
 
 
-bool QgsGeoPackageConnectionItem::deleteGeoPackageRasterLayer( const QString uri, QString &errCause )
+bool QgsGeoPackageConnectionItem::deleteGeoPackageRasterLayer( const QString &uri, QString &errCause )
 {
   bool result = false;
   // Better safe than sorry
@@ -526,7 +526,7 @@ void QgsGeoPackageAbstractLayerItem::deleteLayer()
 
 }
 
-QgsGeoPackageAbstractLayerItem::QgsGeoPackageAbstractLayerItem( QgsDataItem *parent, QString name, QString path, QString uri, QgsLayerItem::LayerType layerType, QString providerKey )
+QgsGeoPackageAbstractLayerItem::QgsGeoPackageAbstractLayerItem( QgsDataItem *parent, const QString &name, const QString &path, const QString &uri, QgsLayerItem::LayerType layerType, const QString &providerKey )
   : QgsLayerItem( parent, name, path, uri, layerType, providerKey )
 {
   setState( Populated ); // no children are expected
@@ -539,14 +539,14 @@ bool QgsGeoPackageAbstractLayerItem::executeDeleteLayer( QString &errCause )
 }
 
 
-QgsGeoPackageVectorLayerItem::QgsGeoPackageVectorLayerItem( QgsDataItem *parent, QString name, QString path, QString uri, LayerType layerType )
+QgsGeoPackageVectorLayerItem::QgsGeoPackageVectorLayerItem( QgsDataItem *parent, const QString &name, const QString &path, const QString &uri, LayerType layerType )
   : QgsGeoPackageAbstractLayerItem( parent, name, path, uri, layerType, QStringLiteral( "ogr" ) )
 {
 
 }
 
 
-QgsGeoPackageRasterLayerItem::QgsGeoPackageRasterLayerItem( QgsDataItem *parent, QString name, QString path, QString uri )
+QgsGeoPackageRasterLayerItem::QgsGeoPackageRasterLayerItem( QgsDataItem *parent, const QString &name, const QString &path, const QString &uri )
   : QgsGeoPackageAbstractLayerItem( parent, name, path, uri, QgsLayerItem::LayerType::Raster, QStringLiteral( "gdal" ) )
 {
 

src/providers/ogr/qgsgeopackagedataitems.h

@@ -28,7 +28,7 @@ class QgsGeoPackageAbstractLayerItem : public QgsLayerItem
     Q_OBJECT
 
   protected:
-    QgsGeoPackageAbstractLayerItem( QgsDataItem *parent, QString name, QString path, QString uri, LayerType layerType, QString providerKey );
+    QgsGeoPackageAbstractLayerItem( QgsDataItem *parent, const QString &name, const QString &path, const QString &uri, LayerType layerType, const QString &providerKey );
 
     /** Subclasses need to implement this function with
      * the real deletion implementation
@@ -47,7 +47,7 @@ class QgsGeoPackageRasterLayerItem : public QgsGeoPackageAbstractLayerItem
     Q_OBJECT
 
   public:
-    QgsGeoPackageRasterLayerItem( QgsDataItem *parent, QString name, QString path, QString uri );
+    QgsGeoPackageRasterLayerItem( QgsDataItem *parent, const QString &name, const QString &path, const QString &uri );
   protected:
     virtual bool executeDeleteLayer( QString &errCause ) override;
 };
@@ -58,7 +58,7 @@ class QgsGeoPackageVectorLayerItem : public QgsGeoPackageAbstractLayerItem
     Q_OBJECT
 
   public:
-    QgsGeoPackageVectorLayerItem( QgsDataItem *parent, QString name, QString path, QString uri, LayerType layerType );
+    QgsGeoPackageVectorLayerItem( QgsDataItem *parent, const QString &name, const QString &path, const QString &uri, LayerType layerType );
   protected:
     virtual bool executeDeleteLayer( QString &errCause ) override;
 };
@@ -69,7 +69,7 @@ class QgsGeoPackageConnectionItem : public QgsDataCollectionItem
     Q_OBJECT
 
   public:
-    QgsGeoPackageConnectionItem( QgsDataItem *parent, QString name, QString path );
+    QgsGeoPackageConnectionItem( QgsDataItem *parent, const QString &name, const QString &path );
     QVector<QgsDataItem *> createChildren() override;
     virtual bool equal( const QgsDataItem *other ) override;
 
@@ -83,7 +83,7 @@ class QgsGeoPackageConnectionItem : public QgsDataCollectionItem
     static QgsLayerItem::LayerType layerTypeFromDb( const QString &geometryType );
 
     //! Delete a geopackage layer
-    static bool deleteGeoPackageRasterLayer( const QString uri, QString &errCause );
+    static bool deleteGeoPackageRasterLayer( const QString &uri, QString &errCause );
 
   public slots:
 #ifdef HAVE_GUI
@@ -102,7 +102,7 @@ class QgsGeoPackageRootItem : public QgsDataCollectionItem
     Q_OBJECT
 
   public:
-    QgsGeoPackageRootItem( QgsDataItem *parent, QString name, QString path );
+    QgsGeoPackageRootItem( QgsDataItem *parent, const QString &name, const QString &path );
 
     QVector<QgsDataItem *> createChildren() override;
 

src/providers/ogr/qgsgeopackagerasterwriter.cpp

@@ -24,7 +24,7 @@
 
 #include <QMessageBox>
 
-QgsGeoPackageRasterWriter::QgsGeoPackageRasterWriter( const QgsMimeDataUtils::Uri sourceUri, const QString outputUrl ):
+QgsGeoPackageRasterWriter::QgsGeoPackageRasterWriter( const QgsMimeDataUtils::Uri &sourceUri, const QString &outputUrl ):
   mSourceUri( sourceUri ),
   mOutputUrl( outputUrl )
 {

src/providers/ogr/qgsgeopackagerasterwriter.h

@@ -35,7 +35,7 @@ class QgsGeoPackageRasterWriter
       ErrUserCanceled, //!< User canceled the export
     };
 
-    QgsGeoPackageRasterWriter( const QgsMimeDataUtils::Uri sourceUri, const QString destinationPath );
+    QgsGeoPackageRasterWriter( const QgsMimeDataUtils::Uri &sourceUri, const QString &destinationPath );
     WriterError writeRaster( QgsFeedback *feedback, QString *errorMessage );
     const QString outputUrl() const { return mOutputUrl; }
 

src/providers/ogr/qgsgeopackagerasterwritertask.cpp

@@ -19,7 +19,7 @@
 ///@cond PRIVATE
 
 
-QgsGeoPackageRasterWriterTask::QgsGeoPackageRasterWriterTask( const QgsMimeDataUtils::Uri sourceUri, const QString destinationPath )
+QgsGeoPackageRasterWriterTask::QgsGeoPackageRasterWriterTask( const QgsMimeDataUtils::Uri &sourceUri, const QString &destinationPath )
   : QgsTask( tr( "Saving %1" ).arg( destinationPath ), QgsTask::CanCancel )
   , mWriter( sourceUri, destinationPath )
   , mFeedback( new QgsFeedback() )

src/providers/ogr/qgsgeopackagerasterwritertask.h

@@ -45,7 +45,7 @@ class QgsGeoPackageRasterWriterTask : public QgsTask
      * Constructor for QgsVectorFileWriterTask. Takes a source \a layer, destination \a fileName
      * and save \a options.
      */
-    QgsGeoPackageRasterWriterTask( const QgsMimeDataUtils::Uri sourceUri, const QString destinationPath );
+    QgsGeoPackageRasterWriterTask( const QgsMimeDataUtils::Uri &sourceUri, const QString &destinationPath );
 
     virtual void cancel() override;
 

src/providers/ogr/qgsogrdataitems.cpp

@@ -43,7 +43,7 @@ QGISEXTERN bool deleteLayer( const QString &uri, const QString &errCause );
 
 
 QgsOgrLayerItem::QgsOgrLayerItem( QgsDataItem *parent,
-                                  QString name, QString path, QString uri, LayerType layerType, bool isSubLayer )
+                                  const QString &name, const QString &path, const QString &uri, LayerType layerType, bool isSubLayer )
   : QgsLayerItem( parent, name, path, uri, layerType, QStringLiteral( "ogr" ) )
 {
   mIsSubLayer = isSubLayer;
@@ -395,7 +395,7 @@ static QgsOgrLayerItem *dataItemForLayer( QgsDataItem *parentItem, QString name,
 
 // ----
 
-QgsOgrDataCollectionItem::QgsOgrDataCollectionItem( QgsDataItem *parent, QString name, QString path )
+QgsOgrDataCollectionItem::QgsOgrDataCollectionItem( QgsDataItem *parent, const QString &name, const QString &path )
   : QgsDataCollectionItem( parent, name, path )
 {
 }

src/providers/ogr/qgsogrdataitems.h

@@ -57,7 +57,7 @@ class QgsOgrLayerItem : public QgsLayerItem
 {
     Q_OBJECT
   public:
-    QgsOgrLayerItem( QgsDataItem *parent, QString name, QString path, QString uri, LayerType layerType, bool isSubLayer = false );
+    QgsOgrLayerItem( QgsDataItem *parent, const QString &name, const QString &path, const QString &uri, LayerType layerType, bool isSubLayer = false );
 
     bool setCrs( const QgsCoordinateReferenceSystem &crs ) override;
 
@@ -81,7 +81,7 @@ class QgsOgrDataCollectionItem : public QgsDataCollectionItem
 {
     Q_OBJECT
   public:
-    QgsOgrDataCollectionItem( QgsDataItem *parent, QString name, QString path );
+    QgsOgrDataCollectionItem( QgsDataItem *parent, const QString &name, const QString &path );
 
     QVector<QgsDataItem *> createChildren() override;
 

src/providers/postgres/qgspostgresdataitems.cpp

@@ -39,7 +39,7 @@ QGISEXTERN bool deleteSchema( const QString &schema, const QgsDataSourceUri &uri
 
 
 // ---------------------------------------------------------------------------
-QgsPGConnectionItem::QgsPGConnectionItem( QgsDataItem *parent, QString name, QString path )
+QgsPGConnectionItem::QgsPGConnectionItem( QgsDataItem *parent, const QString &name, const QString &path )
   : QgsDataCollectionItem( parent, name, path )
 {
   mIconName = QStringLiteral( "mIconConnect.png" );
@@ -706,7 +706,7 @@ bool QgsPGSchemaItem::handleDrop( const QMimeData *data, Qt::DropAction )
 }
 
 // ---------------------------------------------------------------------------
-QgsPGRootItem::QgsPGRootItem( QgsDataItem *parent, QString name, QString path )
+QgsPGRootItem::QgsPGRootItem( QgsDataItem *parent, const QString &name, const QString &path )
   : QgsDataCollectionItem( parent, name, path )
 {
   mCapabilities |= Fast;

src/providers/postgres/qgspostgresdataitems.h

@@ -32,7 +32,7 @@ class QgsPGRootItem : public QgsDataCollectionItem
 {
     Q_OBJECT
   public:
-    QgsPGRootItem( QgsDataItem *parent, QString name, QString path );
+    QgsPGRootItem( QgsDataItem *parent, const QString &name, const QString &path );
 
     QVector<QgsDataItem *> createChildren() override;
 
@@ -55,7 +55,7 @@ class QgsPGConnectionItem : public QgsDataCollectionItem
 {
     Q_OBJECT
   public:
-    QgsPGConnectionItem( QgsDataItem *parent, QString name, QString path );
+    QgsPGConnectionItem( QgsDataItem *parent, const QString &name, const QString &path );
 
     QVector<QgsDataItem *> createChildren() override;
     virtual bool equal( const QgsDataItem *other ) override;

src/providers/spatialite/qgsspatialitedataitems.cpp

@@ -34,7 +34,7 @@
 
 QGISEXTERN bool deleteLayer( const QString &dbPath, const QString &tableName, QString &errCause );
 
-QgsSLLayerItem::QgsSLLayerItem( QgsDataItem *parent, QString name, QString path, QString uri, LayerType layerType )
+QgsSLLayerItem::QgsSLLayerItem( QgsDataItem *parent, const QString &name, const QString &path, const QString &uri, LayerType layerType )
   : QgsLayerItem( parent, name, path, uri, layerType, QStringLiteral( "spatialite" ) )
 {
   setState( Populated ); // no children are expected
@@ -76,7 +76,7 @@ void QgsSLLayerItem::deleteLayer()
 
 // ------
 
-QgsSLConnectionItem::QgsSLConnectionItem( QgsDataItem *parent, QString name, QString path )
+QgsSLConnectionItem::QgsSLConnectionItem( QgsDataItem *parent, const QString &name, const QString &path )
   : QgsDataCollectionItem( parent, name, path )
 {
   mDbPath = QgsSpatiaLiteConnection::connectionPath( name );
@@ -275,7 +275,7 @@ bool QgsSLConnectionItem::handleDrop( const QMimeData *data, Qt::DropAction )
 
 // ---------------------------------------------------------------------------
 
-QgsSLRootItem::QgsSLRootItem( QgsDataItem *parent, QString name, QString path )
+QgsSLRootItem::QgsSLRootItem( QgsDataItem *parent, const QString &name, const QString &path )
   : QgsDataCollectionItem( parent, name, path )
 {
   mCapabilities |= Fast;

src/providers/spatialite/qgsspatialitedataitems.h

@@ -21,7 +21,7 @@ class QgsSLLayerItem : public QgsLayerItem
 {
     Q_OBJECT
   public:
-    QgsSLLayerItem( QgsDataItem *parent, QString name, QString path, QString uri, LayerType layerType );
+    QgsSLLayerItem( QgsDataItem *parent, const QString &name, const QString &path, const QString &uri, LayerType layerType );
 
 #ifdef HAVE_GUI
     QList<QAction *> actions() override;
@@ -37,7 +37,7 @@ class QgsSLConnectionItem : public QgsDataCollectionItem
 {
     Q_OBJECT
   public:
-    QgsSLConnectionItem( QgsDataItem *parent, QString name, QString path );
+    QgsSLConnectionItem( QgsDataItem *parent, const QString &name, const QString &path );
 
     QVector<QgsDataItem *> createChildren() override;
     virtual bool equal( const QgsDataItem *other ) override;
@@ -63,7 +63,7 @@ class QgsSLRootItem : public QgsDataCollectionItem
 {
     Q_OBJECT
   public:
-    QgsSLRootItem( QgsDataItem *parent, QString name, QString path );
+    QgsSLRootItem( QgsDataItem *parent, const QString &name, const QString &path );
 
     QVector<QgsDataItem *> createChildren() override;