vector file writer fixes:

* don't apply un-overridden default options
* DGN: don't export attributes and fix layername to "elements"

(cherry picked from commit 7634b0b)

Author: jef-n

src/app/ogr/qgsvectorlayersaveasdialog.cpp

@@ -347,7 +347,7 @@ void QgsVectorLayerSaveAsDialog::on_mFormatComboBox_currentIndexChanged( int idx
   bool fieldsAsDisplayedValues = false;
 
   const QString sFormat( format() );
-  if ( sFormat == QLatin1String( "DXF" ) )
+  if ( sFormat == QLatin1String( "DXF" ) || sFormat == QLatin1String( "DGN" ) )
   {
     mAttributesSelection->setEnabled( false );
     selectAllFields = false;
@@ -686,24 +686,27 @@ QStringList QgsVectorLayerSaveAsDialog::datasourceOptions() const
       {
         case QgsVectorFileWriter::Int:
         {
+          QgsVectorFileWriter::IntOption *opt = dynamic_cast<QgsVectorFileWriter::IntOption *>( *it );
           QSpinBox *sb = mDatasourceOptionsGroupBox->findChild<QSpinBox *>( it.key() );
-          if ( sb )
+          if ( opt && sb && sb->value() != opt->defaultValue )
             options << QStringLiteral( "%1=%2" ).arg( it.key() ).arg( sb->value() );
           break;
         }
 
         case QgsVectorFileWriter::Set:
         {
+          QgsVectorFileWriter::SetOption *opt = dynamic_cast<QgsVectorFileWriter::SetOption *>( *it );
           QComboBox *cb = mDatasourceOptionsGroupBox->findChild<QComboBox *>( it.key() );
-          if ( cb && !cb->currentData().isNull() )
+          if ( opt && cb && cb->itemData( cb->currentIndex() ) != opt->defaultValue )
             options << QStringLiteral( "%1=%2" ).arg( it.key(), cb->currentText() );
           break;
         }
 
         case QgsVectorFileWriter::String:
         {
+          QgsVectorFileWriter::StringOption *opt = dynamic_cast<QgsVectorFileWriter::StringOption *>( *it );
           QLineEdit *le = mDatasourceOptionsGroupBox->findChild<QLineEdit *>( it.key() );
-          if ( le )
+          if ( opt && le && le->text() != opt->defaultValue )
             options << QStringLiteral( "%1=%2" ).arg( it.key(), le->text() );
           break;
         }
@@ -738,24 +741,26 @@ QStringList QgsVectorLayerSaveAsDialog::layerOptions() const
       {
         case QgsVectorFileWriter::Int:
         {
+          QgsVectorFileWriter::IntOption *opt = dynamic_cast<QgsVectorFileWriter::IntOption *>( *it );
           QSpinBox *sb = mLayerOptionsGroupBox->findChild<QSpinBox *>( it.key() );
-          if ( sb )
-            options << QStringLiteral( "%1=%2" ).arg( it.key() ).arg( sb->value() );
-          break;
+          if ( opt && sb && sb->value() != opt->defaultValue )
+            break;
         }
 
         case QgsVectorFileWriter::Set:
         {
+          QgsVectorFileWriter::SetOption *opt = dynamic_cast<QgsVectorFileWriter::SetOption *>( *it );
           QComboBox *cb = mLayerOptionsGroupBox->findChild<QComboBox *>( it.key() );
-          if ( cb && !cb->currentData().isNull() )
+          if ( opt && cb && cb->itemData( cb->currentIndex() ) != opt->defaultValue )
             options << QStringLiteral( "%1=%2" ).arg( it.key(), cb->currentText() );
           break;
         }
 
         case QgsVectorFileWriter::String:
         {
+          QgsVectorFileWriter::StringOption *opt = dynamic_cast<QgsVectorFileWriter::StringOption *>( *it );
           QLineEdit *le = mLayerOptionsGroupBox->findChild<QLineEdit *>( it.key() );
-          if ( le && !le->text().isEmpty() )
+          if ( opt && le && le->text() != opt->defaultValue )
             options << QStringLiteral( "%1=%2" ).arg( it.key(), le->text() );
           break;
         }

src/core/qgsvectorfilewriter.cpp

@@ -270,6 +270,7 @@ void QgsVectorFileWriter::init( QString vectorFileName,
     options = new char *[ datasourceOptions.size() + 1 ];
     for ( int i = 0; i < datasourceOptions.size(); i++ )
     {
+      QgsDebugMsg( QString( "-dsco=%1" ).arg( datasourceOptions[i] ) );
       options[i] = CPLStrdup( datasourceOptions[i].toLocal8Bit().constData() );
     }
     options[ datasourceOptions.size()] = nullptr;
@@ -374,6 +375,7 @@ void QgsVectorFileWriter::init( QString vectorFileName,
     options = new char *[ layerOptions.size() + 1 ];
     for ( int i = 0; i < layerOptions.size(); i++ )
     {
+      QgsDebugMsg( QString( "-lco=%1" ).arg( layerOptions[i] ) );
       options[i] = CPLStrdup( layerOptions[i].toLocal8Bit().constData() );
     }
     options[ layerOptions.size()] = nullptr;
@@ -382,10 +384,18 @@ void QgsVectorFileWriter::init( QString vectorFileName,
   // disable encoding conversion of OGR Shapefile layer
   CPLSetConfigOption( "SHAPE_ENCODING", "" );
 
-  if ( action == CreateOrOverwriteFile || action == CreateOrOverwriteLayer )
+  if ( driverName == QLatin1String( "DGN" ) )
+  {
+    mLayer = OGR_DS_GetLayerByName( mDS, "elements" );
+  }
+  else if ( action == CreateOrOverwriteFile || action == CreateOrOverwriteLayer )
+  {
     mLayer = OGR_DS_CreateLayer( mDS, layerName.toUtf8().constData(), mOgrRef, wkbType, options );
+  }
   else
+  {
     mLayer = OGR_DS_GetLayerByName( mDS, layerName.toUtf8().constData() );
+  }
 
   if ( options )
   {
@@ -1329,7 +1339,7 @@ QMap<QString, QgsVectorFileWriter::MetaData> QgsVectorFileWriter::initMetaData()
                            false  // Default value
                          ) );
 
-  datasetOptions.insert( QStringLiteral( "COPY_SEED_FILE_COLOR_TABLEE" ), new BoolOption(
+  datasetOptions.insert( QStringLiteral( "COPY_SEED_FILE_COLOR_TABLE" ), new BoolOption(
                            QObject::tr( "Indicates whether the color table should be copied from the seed file." ),
                            false  // Default value
                          ) );