Difference and split with lines can be used in in-place mode

src/analysis/processing/qgsalgorithmdifference.cpp

@@ -16,6 +16,7 @@
 #include "qgsalgorithmdifference.h"
 
 #include "qgsoverlayutils.h"
+#include "qgsvectorlayer.h"
 
 ///@cond PRIVATE
 
@@ -51,6 +52,22 @@ QString QgsDifferenceAlgorithm::shortHelpString() const
                         "be manually updated." );
 }
 
+bool QgsDifferenceAlgorithm::supportInPlaceEdit( const QgsMapLayer *l ) const
+{
+  const QgsVectorLayer *layer = qobject_cast< const QgsVectorLayer * >( l );
+  if ( !layer )
+    return false;
+
+  return layer->isSpatial();
+}
+
+QgsProcessingAlgorithm::Flags QgsDifferenceAlgorithm::flags() const
+{
+  Flags f = QgsProcessingAlgorithm::flags();
+  f |= QgsProcessingAlgorithm::FlagSupportsInPlaceEdits;
+  return f;
+}
+
 QgsProcessingAlgorithm *QgsDifferenceAlgorithm::createInstance() const
 {
   return new QgsDifferenceAlgorithm();

src/analysis/processing/qgsalgorithmdifference.h

@@ -33,7 +33,8 @@ class QgsDifferenceAlgorithm : public QgsProcessingAlgorithm
     QString group() const override;
     QString groupId() const override;
     QString shortHelpString() const override;
-
+    bool supportInPlaceEdit( const QgsMapLayer *layer ) const override;
+    QgsProcessingAlgorithm::Flags flags() const override;
   protected:
     QgsProcessingAlgorithm *createInstance() const override;
     void initAlgorithm( const QVariantMap &configuration = QVariantMap() ) override;

src/analysis/processing/qgsalgorithmsplitwithlines.cpp

@@ -17,7 +17,7 @@
 
 #include "qgsalgorithmsplitwithlines.h"
 #include "qgsgeometryengine.h"
-
+#include "qgsvectorlayer.h"
 ///@cond PRIVATE
 
 QString QgsSplitWithLinesAlgorithm::name() const
@@ -65,6 +65,22 @@ QgsSplitWithLinesAlgorithm *QgsSplitWithLinesAlgorithm::createInstance() const
   return new QgsSplitWithLinesAlgorithm();
 }
 
+QgsProcessingAlgorithm::Flags QgsSplitWithLinesAlgorithm::flags() const
+{
+  Flags f = QgsProcessingAlgorithm::flags();
+  f |= QgsProcessingAlgorithm::FlagSupportsInPlaceEdits;
+  return f;
+}
+
+bool QgsSplitWithLinesAlgorithm::supportInPlaceEdit( const QgsMapLayer *l ) const
+{
+  const QgsVectorLayer *layer = qobject_cast< const QgsVectorLayer * >( l );
+  if ( !layer )
+    return false;
+
+  return true;
+}
+
 QVariantMap QgsSplitWithLinesAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
 {
   std::unique_ptr< QgsFeatureSource > source( parameterAsSource( parameters, QStringLiteral( "INPUT" ), context ) );

src/analysis/processing/qgsalgorithmsplitwithlines.h

@@ -43,7 +43,8 @@ class QgsSplitWithLinesAlgorithm : public QgsProcessingAlgorithm
     QString groupId() const override;
     QString shortHelpString() const override;
     QgsSplitWithLinesAlgorithm *createInstance() const override SIP_FACTORY;
-
+    QgsProcessingAlgorithm::Flags flags() const override;
+    bool supportInPlaceEdit( const QgsMapLayer *layer ) const override;
   protected:
 
     QVariantMap processAlgorithm( const QVariantMap &parameters,