Merge pull request #6603 from slarosa/fix_18435

Fixes #18435: QGIS crash when deleting auxiliary layer

Author: luipir

src/core/qgsvectorlayer.cpp

@@ -4304,7 +4304,8 @@ void QgsVectorLayer::setAuxiliaryLayer( QgsAuxiliaryLayer *alayer )
   }
 
   mAuxiliaryLayer.reset( alayer );
-  mAuxiliaryLayer->setParent( this );
+  if ( mAuxiliaryLayer )
+    mAuxiliaryLayer->setParent( this );
   updateFields();
 }
 

tests/src/python/test_qgsauxiliarystorage.py

@@ -361,6 +361,26 @@ def testClear(self):
         al.clear()
         self.assertEqual(al.featureCount(), 0)
 
+    def testSetAuxiliaryLayer(self):
+        s = QgsAuxiliaryStorage()
+        self.assertTrue(s.isValid())
+
+        # Create a new auxiliary layer with 'pk' as key
+        vl = createLayer()
+        pkf = vl.fields().field(vl.fields().indexOf('pk'))
+        al = s.createAuxiliaryLayer(pkf, vl)
+        self.assertTrue(al.isValid())
+        vl.setAuxiliaryLayer(al)
+
+        self.assertIsNotNone(vl.auxiliaryLayer())
+
+        # Clear auxiliary layer
+        al.clear()
+        # Remove auxiliary layer
+        vl.setAuxiliaryLayer()
+
+        self.assertIsNone(vl.auxiliaryLayer())
+
     def testCreateProperty(self):
         s = QgsAuxiliaryStorage()
         self.assertTrue(s.isValid())