Add mandatory options to QgsVectorLayer ctor

... and deprecate the rest.

In QGIS 4 we'll have to get rid of the deprecated default ctor and
create a new one which takes no arguments.

python/core/auto_generated/qgsvectorlayer.sip.in

@@ -352,6 +352,7 @@ Constructor for LayerOptions.
 
     };
 
+
  explicit QgsVectorLayer( const QString &path = QString(), const QString &baseName = QString(),
         const QString &providerLib = "ogr", const QgsVectorLayer::LayerOptions &options = QgsVectorLayer::LayerOptions() ) /Deprecated/;
 %Docstring

python/core/auto_generated/raster/qgsrasterlayer.sip.in

@@ -104,12 +104,21 @@ Constructor. Provider is not set.
     struct LayerOptions
     {
 
-      explicit LayerOptions( bool loadDefaultStyle = true,
-                             const QgsCoordinateTransformContext &transformContext = QgsCoordinateTransformContext() );
+ explicit LayerOptions( bool loadDefaultStyle = true ) /Deprecated/;
 %Docstring
 Constructor for LayerOptions.
+
+.. deprecated:: Use version with transformContext argument instead
+%End
+
+      explicit LayerOptions( const QgsCoordinateTransformContext &transformContext, bool loadDefaultStyle = true );
+%Docstring
+Constructor for LayerOptions.
+
+.. versionadded:: 3.10
 %End
 
+
       bool loadDefaultStyle;
 
       QgsCoordinateTransformContext transformContext;

src/app/browser/qgsinbuiltdataitemproviders.cpp

@@ -363,7 +363,8 @@ void QgsLayerItemGuiProvider::populateContextMenu( QgsDataItem *item, QMenu *men
       {
         case QgsMapLayerType::VectorLayer:
         {
-          std::unique_ptr<QgsVectorLayer> layer( new QgsVectorLayer( layerItem->uri(), layerItem->name(), layerItem->providerKey() ) );
+          const QgsVectorLayer::LayerOptions options { QgsProject::instance()->transformContext() };
+          std::unique_ptr<QgsVectorLayer> layer( new QgsVectorLayer( options, layerItem->uri(), layerItem->name(), layerItem->providerKey() ) );
           if ( layer && layer->isValid() )
           {
             QgisApp::instance()->saveAsFile( layer.get(), false, false );

src/app/dwg/qgsdwgimportdialog.cpp

@@ -148,9 +148,9 @@ void QgsDwgImportDialog::pbLoadDatabase_clicked()
 
   bool lblVisible = false;
 
-  QgsVectorLayer::LayerOptions options;
+  QgsVectorLayer::LayerOptions options { QgsProject::instance()->transformContext() };
   options.loadDefaultStyle = false;
-  std::unique_ptr<QgsVectorLayer> d( new QgsVectorLayer( QStringLiteral( "%1|layername=drawing" ).arg( mDatabaseFileWidget->filePath() ), QStringLiteral( "layers" ), QStringLiteral( "ogr" ), options ) );
+  std::unique_ptr<QgsVectorLayer> d( new QgsVectorLayer( options, QStringLiteral( "%1|layername=drawing" ).arg( mDatabaseFileWidget->filePath() ), QStringLiteral( "layers" ), QStringLiteral( "ogr" ) ) );
   if ( d && d->isValid() )
   {
     int idxPath = d->fields().lookupField( QStringLiteral( "path" ) );
@@ -185,7 +185,7 @@ void QgsDwgImportDialog::pbLoadDatabase_clicked()
 
   lblMessage->setVisible( lblVisible );
 
-  std::unique_ptr<QgsVectorLayer> l( new QgsVectorLayer( QStringLiteral( "%1|layername=layers" ).arg( mDatabaseFileWidget->filePath() ), QStringLiteral( "layers" ), QStringLiteral( "ogr" ), options ) );
+  std::unique_ptr<QgsVectorLayer> l( new QgsVectorLayer( options, QStringLiteral( "%1|layername=layers" ).arg( mDatabaseFileWidget->filePath() ), QStringLiteral( "layers" ), QStringLiteral( "ogr" ) ) );
   if ( l && l->isValid() )
   {
     int idxName = l->fields().lookupField( QStringLiteral( "name" ) );
@@ -263,9 +263,9 @@ void QgsDwgImportDialog::pbImportDrawing_clicked()
 
 QgsVectorLayer *QgsDwgImportDialog::layer( QgsLayerTreeGroup *layerGroup, const QString &layerFilter, const QString &table )
 {
-  QgsVectorLayer::LayerOptions options;
+  QgsVectorLayer::LayerOptions options { QgsProject::instance()->transformContext() };
   options.loadDefaultStyle = false;
-  QgsVectorLayer *l = new QgsVectorLayer( QStringLiteral( "%1|layername=%2" ).arg( mDatabaseFileWidget->filePath(), table ), table, QStringLiteral( "ogr" ), options );
+  QgsVectorLayer *l = new QgsVectorLayer( options, QStringLiteral( "%1|layername=%2" ).arg( mDatabaseFileWidget->filePath(), table ), table, QStringLiteral( "ogr" ) );
   l->setSubsetString( QStringLiteral( "%1space=0 AND block=-1" ).arg( layerFilter ) );
 
   if ( l->featureCount() == 0 )

src/app/qgisapp.cpp

@@ -4638,7 +4638,7 @@ static void setupVectorLayer( const QString &vectorLayerPath,
     QString composedURI( uriParts.value( QStringLiteral( "path" ) ).toString() );
     composedURI += "|layername=" + rawLayerName;
 
-    auto newLayer = qgis::make_unique<QgsVectorLayer>( composedURI, layer->name(), QStringLiteral( "ogr" ), options );
+    auto newLayer = qgis::make_unique<QgsVectorLayer>( options, composedURI, layer->name(), QStringLiteral( "ogr" ) );
     if ( newLayer && newLayer->isValid() )
     {
       delete layer;
@@ -4716,7 +4716,7 @@ bool QgisApp::addVectorLayersPrivate( const QStringList &layerQStringList, const
       QApplication::setOverrideCursor( Qt::WaitCursor );
       qApp->processEvents();
     }
-    QgsVectorLayer *layer = new QgsVectorLayer( src, baseName, QStringLiteral( "ogr" ), options );
+    QgsVectorLayer *layer = new QgsVectorLayer( options, src, baseName, QStringLiteral( "ogr" ) );
     Q_CHECK_PTR( layer );
     if ( isVsiCurl || isRemoteUrl )
     {
@@ -5256,7 +5256,7 @@ QList<QgsMapLayer *> QgisApp::askUserForOGRSublayers( QgsVectorLayer *layer )
     QString name = fileName + " " + def.layerName;
     QgsVectorLayer::LayerOptions options { QgsProject::instance()->transformContext() };
     options.loadDefaultStyle = false;
-    QgsVectorLayer *layer = new QgsVectorLayer( composedURI, name, QStringLiteral( "ogr" ), options );
+    QgsVectorLayer *layer = new QgsVectorLayer( options, composedURI, name, QStringLiteral( "ogr" ) );
     if ( layer && layer->isValid() )
     {
       result << layer;
@@ -5320,7 +5320,7 @@ void QgisApp::addDatabaseLayers( QStringList const &layerPathList, QString const
 
     QgsVectorLayer::LayerOptions options { QgsProject::instance()->transformContext() };
     options.loadDefaultStyle = false;
-    QgsVectorLayer *layer = new QgsVectorLayer( uri.uri( false ), uri.table(), providerKey, options );
+    QgsVectorLayer *layer = new QgsVectorLayer( options, uri.uri( false ), uri.table(), providerKey );
     Q_CHECK_PTR( layer );
 
     if ( ! layer )
@@ -5397,7 +5397,8 @@ void QgisApp::replaceSelectedVectorLayer( const QString &oldId, const QString &u
   if ( !old )
     return;
   QgsVectorLayer *oldLayer = static_cast<QgsVectorLayer *>( old );
-  QgsVectorLayer *newLayer = new QgsVectorLayer( uri, layerName, provider );
+  const QgsVectorLayer::LayerOptions options { QgsProject::instance()->transformContext() };
+  QgsVectorLayer *newLayer = new QgsVectorLayer( options, uri, layerName, provider );
   if ( !newLayer || !newLayer->isValid() )
     return;
 
@@ -9853,7 +9854,8 @@ void QgisApp::layerSubsetString()
                                 QMessageBox::Yes | QMessageBox::No ) == QMessageBox::Yes )
     {
       QgsVirtualLayerDefinition def = QgsVirtualLayerDefinitionUtils::fromJoinedLayer( vlayer );
-      QgsVectorLayer *newLayer = new QgsVectorLayer( def.toString(), vlayer->name() + " (virtual)", QStringLiteral( "virtual" ) );
+      const QgsVectorLayer::LayerOptions options { QgsProject::instance()->transformContext() };
+      QgsVectorLayer *newLayer = new QgsVectorLayer( options, def.toString(), vlayer->name() + " (virtual)", QStringLiteral( "virtual" ) );
       if ( newLayer->isValid() )
       {
         duplicateVectorStyle( vlayer, newLayer );
@@ -11111,7 +11113,7 @@ QgsVectorLayer *QgisApp::addVectorLayerPrivate( const QString &vectorLayerPath,
   QgsVectorLayer::LayerOptions options { QgsProject::instance()->transformContext() };
   // Default style is loaded later in this method
   options.loadDefaultStyle = false;
-  QgsVectorLayer *layer = new QgsVectorLayer( vectorLayerPath, baseName, providerKey, options );
+  QgsVectorLayer *layer = new QgsVectorLayer( options, vectorLayerPath, baseName, providerKey );
 
   if ( authok && layer && layer->isValid() )
   {

src/app/qgsappscreenshots.cpp

@@ -42,9 +42,10 @@ QgsAppScreenShots::QgsAppScreenShots( const QString &saveDirectory )
   : mSaveDirectory( saveDirectory )
 {
   QString layerDef = QStringLiteral( "Point?crs=epsg:4326&field=pk:integer&field=my_text:string&field=fk_polygon:integer&field=my_double:double&key=pk" );
-  mLineLayer = new QgsVectorLayer( layerDef, QStringLiteral( "Line Layer" ), QStringLiteral( "memory" ) );
+  const QgsVectorLayer::LayerOptions options { QgsProject::instance()->transformContext() };
+  mLineLayer = new QgsVectorLayer( options, layerDef, QStringLiteral( "Line Layer" ), QStringLiteral( "memory" ) );
   layerDef = QStringLiteral( "Polygon?crs=epsg:2056&field=pk:integer&field=my_text:string&field=my_integer:integer&field=height:double&key=pk" );
-  mPolygonLayer = new QgsVectorLayer( layerDef, QStringLiteral( "Polygon Layer" ), QStringLiteral( "memory" ) );
+  mPolygonLayer = new QgsVectorLayer( options, layerDef, QStringLiteral( "Polygon Layer" ), QStringLiteral( "memory" ) );
 
   QString dataPath( TEST_DATA_DIR ); //defined in CmakeLists.txt
   mRasterLayer = new QgsRasterLayer( dataPath + "/raster/with_color_table.tif", QStringLiteral( "raster" ), QStringLiteral( "gdal" ) );

src/app/qgsnewspatialitelayerdialog.cpp

@@ -454,7 +454,8 @@ bool QgsNewSpatialiteLayerDialog::apply()
     }
   }
 
-  QgsVectorLayer *layer = new QgsVectorLayer( QStringLiteral( "dbname='%1' table='%2'%3 sql=" )
+  const QgsVectorLayer::LayerOptions options { QgsProject::instance()->transformContext() };
+  QgsVectorLayer *layer = new QgsVectorLayer( options, QStringLiteral( "dbname='%1' table='%2'%3 sql=" )
       .arg( mDatabaseComboBox->currentText(),
             leLayerName->text(),
             mGeometryTypeBox->currentIndex() != 0 ? QStringLiteral( "(%1)" ).arg( leGeometryColumn->text() ) : QString() ),

src/app/qgsstatusbarcoordinateswidget.cpp

@@ -212,7 +212,8 @@ void QgsStatusBarCoordinatesWidget::contributors()
   }
   QString fileName = QgsApplication::pkgDataPath() + QStringLiteral( "/resources/data/contributors.json" );
   QFileInfo fileInfo = QFileInfo( fileName );
-  QgsVectorLayer *layer = new QgsVectorLayer( fileInfo.absoluteFilePath(),
+  const QgsVectorLayer::LayerOptions options { QgsProject::instance()->transformContext() };
+  QgsVectorLayer *layer = new QgsVectorLayer( options, fileInfo.absoluteFilePath(),
       tr( "QGIS Contributors" ), QStringLiteral( "ogr" ) );
   // Register this layer with the layers registry
   QgsProject::instance()->addMapLayer( layer );
@@ -228,7 +229,8 @@ void QgsStatusBarCoordinatesWidget::world()
   }
   QString fileName = QgsApplication::pkgDataPath() + QStringLiteral( "/resources/data/world_map.shp" );
   QFileInfo fileInfo = QFileInfo( fileName );
-  QgsVectorLayer *layer = new QgsVectorLayer( fileInfo.absoluteFilePath(),
+  const QgsVectorLayer::LayerOptions options { QgsProject::instance()->transformContext() };
+  QgsVectorLayer *layer = new QgsVectorLayer( options, fileInfo.absoluteFilePath(),
       tr( "World Map" ), QStringLiteral( "ogr" ) );
   // Register this layer with the layers registry
   QgsProject::instance()->addMapLayer( layer );
@@ -242,7 +244,8 @@ void QgsStatusBarCoordinatesWidget::hackfests()
   }
   QString fileName = QgsApplication::pkgDataPath() + QStringLiteral( "/resources/data/qgis-hackfests.json" );
   QFileInfo fileInfo = QFileInfo( fileName );
-  QgsVectorLayer *layer = new QgsVectorLayer( fileInfo.absoluteFilePath(),
+  const QgsVectorLayer::LayerOptions options { QgsProject::instance()->transformContext() };
+  QgsVectorLayer *layer = new QgsVectorLayer( options, fileInfo.absoluteFilePath(),
       tr( "QGIS Hackfests" ), QStringLiteral( "ogr" ) );
   // Register this layer with the layers registry
   QgsProject::instance()->addMapLayer( layer );

src/core/layout/qgslayoutitemmapoverview.cpp

@@ -33,7 +33,7 @@
 
 QgsLayoutItemMapOverview::QgsLayoutItemMapOverview( const QString &name, QgsLayoutItemMap *map )
   : QgsLayoutItemMapItem( name, map )
-  , mExtentLayer( qgis::make_unique< QgsVectorLayer >( QStringLiteral( "Polygon?crs=EPSG:4326" ), QStringLiteral( "overview" ), QStringLiteral( "memory" ) ) )
+  , mExtentLayer( qgis::make_unique< QgsVectorLayer >( QgsVectorLayer::LayerOptions( QgsCoordinateTransformContext() ), QStringLiteral( "Polygon?crs=EPSG:4326" ), QStringLiteral( "overview" ), QStringLiteral( "memory" ) ) )
 {
   createDefaultFrameSymbol();
 }

src/core/processing/qgsprocessingutils.cpp

@@ -214,7 +214,7 @@ class ProjectionSettingRestorer
 };
 ///@endcond PRIVATE
 
-QgsMapLayer *QgsProcessingUtils::loadMapLayerFromString( const QString &string, LayerHint typeHint )
+QgsMapLayer *QgsProcessingUtils::loadMapLayerFromString( const QString &string, const QgsCoordinateTransformContext &transformContext, LayerHint typeHint )
 {
   QStringList components = string.split( '|' );
   if ( components.isEmpty() )
@@ -237,9 +237,9 @@ QgsMapLayer *QgsProcessingUtils::loadMapLayerFromString( const QString &string,
   // brute force attempt to load a matching layer
   if ( typeHint == LayerHint::UnknownType || typeHint == LayerHint::Vector )
   {
-    QgsVectorLayer::LayerOptions options;
+    QgsVectorLayer::LayerOptions options { transformContext };
     options.loadDefaultStyle = false;
-    std::unique_ptr< QgsVectorLayer > layer( new QgsVectorLayer( string, name, QStringLiteral( "ogr" ), options ) );
+    std::unique_ptr< QgsVectorLayer > layer = qgis::make_unique<QgsVectorLayer>( options, string, name, QStringLiteral( "ogr" ) );
     if ( layer->isValid() )
     {
       return layer.release();
@@ -288,7 +288,7 @@ QgsMapLayer *QgsProcessingUtils::mapLayerFromString( const QString &string, QgsP
   if ( !allowLoadingNewLayers )
     return nullptr;
 
-  layer = loadMapLayerFromString( string, typeHint );
+  layer = loadMapLayerFromString( string, context.transformContext(), typeHint );
   if ( layer )
   {
     context.temporaryLayerStore()->addMapLayer( layer );
@@ -601,7 +601,8 @@ QgsFeatureSink *QgsProcessingUtils::createFeatureSink( QString &destination, Qgs
     else
     {
       //create empty layer
-      std::unique_ptr< QgsVectorLayerExporter > exporter( new QgsVectorLayerExporter( uri, providerKey, newFields, geometryType, crs, true, options, sinkFlags ) );
+      const QgsVectorLayer::LayerOptions layerOptions { context.transformContext() };
+      std::unique_ptr< QgsVectorLayerExporter > exporter = qgis::make_unique<QgsVectorLayerExporter>( uri, providerKey, newFields, geometryType, crs, true, options, sinkFlags );
       if ( exporter->errorCode() )
       {
         throw QgsProcessingException( QObject::tr( "Could not create layer %1: %2" ).arg( destination, exporter->errorMessage() ) );
@@ -610,15 +611,14 @@ QgsFeatureSink *QgsProcessingUtils::createFeatureSink( QString &destination, Qgs
       // use destination string as layer name (eg "postgis:..." )
       if ( !layerName.isEmpty() )
         uri += QStringLiteral( "|layername=%1" ).arg( layerName );
-      std::unique_ptr< QgsVectorLayer > layer( new QgsVectorLayer( uri, destination, providerKey ) );
+      std::unique_ptr< QgsVectorLayer > layer = qgis::make_unique<QgsVectorLayer>( layerOptions, uri, destination, providerKey );
       // update destination to layer ID
       destination = layer->id();
 
       context.temporaryLayerStore()->addMapLayer( layer.release() );
       return new QgsProcessingFeatureSink( exporter.release(), destination, context, true );
     }
   }
-  return nullptr;
 }
 
 void QgsProcessingUtils::createFeatureSinkPython( QgsFeatureSink **sink, QString &destination, QgsProcessingContext &context, const QgsFields &fields, QgsWkbTypes::Type geometryType, const QgsCoordinateReferenceSystem &crs, const QVariantMap &options )

src/core/processing/qgsprocessingutils.h

@@ -310,13 +310,27 @@ class CORE_EXPORT QgsProcessingUtils
      */
     static QgsMapLayer *mapLayerFromStore( const QString &string, QgsMapLayerStore *store, QgsProcessingUtils::LayerHint typeHint = QgsProcessingUtils::LayerHint::UnknownType );
 
+    /**
+     * Interprets a string as a map layer. The method will attempt to
+     * load a layer matching the passed \a string using the given coordinate
+     * \a transformContext.
+     * E.g. if the string is a file path,
+     * then the layer at this file path will be loaded.
+     * The caller takes responsibility for deleting the returned map layer.
+     *
+     * \since QGIS 3.8
+     */
+    static QgsMapLayer *loadMapLayerFromString( const QString &string, const QgsCoordinateTransformContext &transformContext, LayerHint typeHint = UnknownType );
+
     /**
      * Interprets a string as a map layer. The method will attempt to
      * load a layer matching the passed \a string. E.g. if the string is a file path,
      * then the layer at this file path will be loaded.
      * The caller takes responsibility for deleting the returned map layer.
+     *
+     * \deprecated use mapLayerFromString() that takes QgsCoordinateTransformContext as an argument instead
      */
-    static QgsMapLayer *loadMapLayerFromString( const QString &string, QgsProcessingUtils::LayerHint typeHint = QgsProcessingUtils::LayerHint::UnknownType );
+    Q_DECL_DEPRECATED static QgsMapLayer *loadMapLayerFromString( const QString &string, LayerHint typeHint = UnknownType ) SIP_DEPRECATED ;
 
     static void parseDestinationString( QString &destination, QString &providerKey, QString &uri, QString &layerName, QString &format, QMap<QString, QVariant> &options, bool &useWriter, QString &extension );
 

src/core/providers/memory/qgsmemoryproviderutils.cpp

@@ -74,6 +74,5 @@ QgsVectorLayer *QgsMemoryProviderUtils::createMemoryLayer( const QString &name,
   }
 
   QString uri = geomType + '?' + parts.join( '&' );
-
-  return new QgsVectorLayer( uri, name, QStringLiteral( "memory" ) );
+  return new QgsVectorLayer( QgsVectorLayer::LayerOptions( QgsCoordinateTransformContext() ), uri, name, QStringLiteral( "memory" ) );
 }

src/core/qgsauxiliarystorage.cpp

@@ -61,7 +61,9 @@ const QVector<QgsPalLayerSettings::Property> palHiddenProperties
 //
 
 QgsAuxiliaryLayer::QgsAuxiliaryLayer( const QString &pkField, const QString &filename, const QString &table, QgsVectorLayer *vlayer )
-  : QgsVectorLayer( QString( "%1|layername=%2" ).arg( filename, table ), QString( "%1_auxiliarystorage" ).arg( table ), "ogr" )
+  : QgsVectorLayer( QgsVectorLayer::LayerOptions( QgsCoordinateTransformContext( ) ),
+                    QString( "%1|layername=%2" ).arg( filename, table ),
+                    QString( "%1_auxiliarystorage" ).arg( table ), "ogr" )
   , mFileName( filename )
   , mTable( table )
   , mLayer( vlayer )

src/core/qgslayerdefinition.cpp

@@ -265,7 +265,8 @@ QList<QgsMapLayer *> QgsLayerDefinition::loadLayerDefinitionLayers( QDomDocument
 
     if ( type == QLatin1String( "vector" ) )
     {
-      layer = new QgsVectorLayer;
+      const QgsVectorLayer::LayerOptions options { QgsCoordinateTransformContext() };
+      layer = new QgsVectorLayer( options );
     }
     else if ( type == QLatin1String( "raster" ) )
     {

src/core/qgsmimedatautils.cpp

@@ -94,7 +94,8 @@ QgsVectorLayer *QgsMimeDataUtils::Uri::vectorLayer( bool &owner, QString &error
     return vectorLayer;
   }
   owner = true;
-  return new QgsVectorLayer( uri, name, providerKey );
+  const QgsVectorLayer::LayerOptions options { QgsProject::instance()->transformContext() };
+  return new QgsVectorLayer( options, uri, name, providerKey );
 }
 
 QgsRasterLayer *QgsMimeDataUtils::Uri::rasterLayer( bool &owner, QString &error ) const