Optimise retrieval of feature from context

(cherry picked from commit 4113505)
qgis · Mar 7, 2019 · 1b4e592 · 1b4e592
1 parent afaaabf
commit 1b4e592
Showing 1 changed file with 8 additions and 5 deletions.
diff --git a/src/core/expression/qgsexpressionnodeimpl.cpp b/src/core/expression/qgsexpressionnodeimpl.cpp
@@ -1237,13 +1237,16 @@ QVariant QgsExpressionNodeColumnRef::evalNode( QgsExpression *parent, const QgsE
     }
   }
 
-  if ( context && context->hasFeature() )
+  if ( context )
   {
     QgsFeature feature = context->feature();
-    if ( index >= 0 )
-      return feature.attribute( index );
-    else
-      return feature.attribute( mName );
+    if ( feature.isValid() )
+    {
+      if ( index >= 0 )
+        return feature.attribute( index );
+      else
+        return feature.attribute( mName );
+    }
   }
   return QVariant( '[' + mName + ']' );
 }