NodeDiff nodeDiff = graph.getNodeDiff();
if (bodyNode != null) {
ClassTag oldTag = getClassTag(klass);
if (nodeDiff != null && oldTag != null) {
List<Node> partialDiff = nodeDiff.diff(bodyNode, oldTag.getBodyNode());
if (partialDiff != null) {
Logger.debug(SourceLocation.of(bodyNode), "class partial update: %s %s", klass, partialDiff.size());
for (Node dirty : partialDiff) {
graph.createVertex(dirty);
}