Adding the node at the starting point of a circular reference to the circular nodes now

Author: SQiShER

src/main/java/de/danielbechler/diff/DifferDelegator.java

@@ -71,8 +71,7 @@ private Node delegateWithCircularReferenceTracking(final Node parentNode, final
 		}
 		catch (CircularReferenceException e)
 		{
-			node = newCircularNode(parentNode, instances);
-			node.setCircleStartPath(e.getPropertyPath());
+			node = newCircularNode(parentNode, instances, e.getPropertyPath());
 			logCircularReference(node.getPropertyPath());
 		}
 		if (parentNode == null)
@@ -82,16 +81,32 @@ private Node delegateWithCircularReferenceTracking(final Node parentNode, final
 		return node;
 	}
 
+	private Node findNodeMatchingPropertyPath(final Node node, final PropertyPath propertyPath)
+	{
+		if (node == null)
+		{
+			return null;
+		}
+		if (node.matches(propertyPath))
+		{
+			return node;
+		}
+		return findNodeMatchingPropertyPath(node.getParentNode(), propertyPath);
+	}
+
 	private static Node newDefaultNode(final Node parentNode, final Instances instances, final Class<?> type)
 	{
 		return new DefaultNode(parentNode, instances.getSourceAccessor(), type);
 	}
 
-	private static Node newCircularNode(final Node parentNode,
-										final Instances instances)
+	private Node newCircularNode(final Node parentNode,
+								 final Instances instances,
+								 final PropertyPath circleStartPath)
 	{
 		final Node node = new DefaultNode(parentNode, instances.getSourceAccessor(), instances.getType());
 		node.setState(Node.State.CIRCULAR);
+		node.setCircleStartPath(circleStartPath);
+		node.setCircleStartNode(findNodeMatchingPropertyPath(parentNode, circleStartPath));
 		return node;
 	}
 

src/main/java/de/danielbechler/diff/node/DefaultNode.java

@@ -33,6 +33,7 @@ public class DefaultNode implements Node
 	private State state = State.UNTOUCHED;
 	private Node parentNode;
 	private PropertyPath circleStartPath;
+	private Node circleStartNode;
 	private Class<?> valueType;
 
 	public DefaultNode(final Node parentNode, final Accessor accessor, final Class<?> valueType)
@@ -441,4 +442,14 @@ public void setCircleStartPath(final PropertyPath circularStartPath)
 	{
 		this.circleStartPath = circularStartPath;
 	}
+
+	public Node getCircleStartNode()
+	{
+		return circleStartNode;
+	}
+
+	public void setCircleStartNode(final Node circleStartNode)
+	{
+		this.circleStartNode = circleStartNode;
+	}
 }

src/main/java/de/danielbechler/diff/node/Node.java

@@ -119,6 +119,10 @@ public enum State
 	 */
 	PropertyPath getCircleStartPath();
 
+	void setCircleStartNode(Node node);
+
+	Node getCircleStartNode();
+
 	/** @return Returns the type of the property represented by this node, or null if unavailable. */
 	Class<?> getType();
 

src/test/java/de/danielbechler/diff/integration/graph/CircularReferenceIntegrationTest.java

@@ -49,6 +49,8 @@ public void testCircularReference()
 
 		Assertions.assertThat(root.canonicalGet(workingA))
 				  .isSameAs(root.getChild("reference").getChild("reference").canonicalGet(workingA));
+		Assertions.assertThat(root.getChild("reference").getChild("reference").getCircleStartNode())
+				  .isSameAs(root);
 	}
 
 	@Test