Merge pull request #2556 from mhugo/fix_nullp

Avoid insertion of null pointers in layer registry

Author: Hugo Mercier

src/core/qgsmaplayerregistry.cpp

@@ -119,7 +119,7 @@ void QgsMapLayerRegistry::removeMapLayers( const QStringList& theLayerIds )
   QList<QgsMapLayer*> layers;
   Q_FOREACH ( const QString &myId, theLayerIds )
   {
-    layers << mMapLayers[myId];
+    layers << mMapLayers.value( myId );
   }
 
   removeMapLayers( layers );
@@ -160,12 +160,13 @@ void QgsMapLayerRegistry::removeMapLayers( const QList<QgsMapLayer*>& layers )
 
 void QgsMapLayerRegistry::removeMapLayer( const QString& theLayerId )
 {
-  removeMapLayers( QList<QgsMapLayer*>() << mMapLayers[theLayerId] );
+  removeMapLayers( QList<QgsMapLayer*>() << mMapLayers.value( theLayerId ) );
 }
 
 void QgsMapLayerRegistry::removeMapLayer( QgsMapLayer* layer )
 {
-  removeMapLayers( QList<QgsMapLayer*>() << layer );
+  if ( layer )
+    removeMapLayers( QList<QgsMapLayer*>() << layer );
 }
 
 void QgsMapLayerRegistry::removeAllMapLayers()

tests/src/python/test_qgsmaplayerregistry.py

@@ -25,6 +25,11 @@ def test_RemoveLayerShouldNotSegFault(self):
         reg = QgsMapLayerRegistry.instance()
         # Should not segfault
         reg.removeMapLayers(['not_exists'])
+        reg.removeMapLayer('not_exists2')
+
+        # check also that the removal of an unexistant layer does not insert a null layer
+        for k, layer in reg.mapLayers().items():
+            assert(layer is not None)
 
 
 if __name__ == '__main__':