From c772e90d686d9dd1d43b90cbcca4def924720257 Mon Sep 17 00:00:00 2001
From: Paul Campbell <pcampbell@kemitix.net>
Date: Sat, 18 Feb 2017 10:26:23 +0000
Subject: [PATCH] Node: streamParents(): added

---
 src/main/java/net/kemitix/node/Node.java     | 7 +++++++
 src/main/java/net/kemitix/node/NodeItem.java | 6 ++++++
 2 files changed, 13 insertions(+)

diff --git a/src/main/java/net/kemitix/node/Node.java b/src/main/java/net/kemitix/node/Node.java
index 6477681..ac16cb3 100644
--- a/src/main/java/net/kemitix/node/Node.java
+++ b/src/main/java/net/kemitix/node/Node.java
@@ -250,4 +250,11 @@ public interface Node<T> {
      * @return a stream of all the nodes in the tree below this node
      */
     Stream<Node<T>> streamAll();
+
+    /**
+     * Returns a stream of all the node's ancestor nodes.
+     *
+     * @return a stream of the node's parents recursively until the root node
+     */
+    Stream<Node<T>> streamParents();
 }
diff --git a/src/main/java/net/kemitix/node/NodeItem.java b/src/main/java/net/kemitix/node/NodeItem.java
index 70724c5..2c96f3f 100644
--- a/src/main/java/net/kemitix/node/NodeItem.java
+++ b/src/main/java/net/kemitix/node/NodeItem.java
@@ -375,4 +375,10 @@ class NodeItem<T> implements Node<T> {
         return Stream.concat(Stream.of(this), getChildren().stream()
                                                            .flatMap(Node::streamAll));
     }
+
+    @Override
+    public Stream<Node<T>> streamParents() {
+        return getParent().map(node -> Stream.concat(Stream.of(node), node.streamParents()))
+                          .orElseGet(Stream::empty);
+    }
 }