From 4eee1f521074164244c16ec1f40a1efaed395dea Mon Sep 17 00:00:00 2001
From: ansuz <ansuz@transitiontech.ca>
Date: Mon, 22 Feb 2016 17:56:17 +0100
Subject: [PATCH] add orderOfNodes function to tree library

---
 www/common/treesome.js | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/www/common/treesome.js b/www/common/treesome.js
index 1c6b69ab5..08743b1c7 100644
--- a/www/common/treesome.js
+++ b/www/common/treesome.js
@@ -146,7 +146,7 @@ define([], function () {
             if (root && el.parentNode === root.childNodes[0]) { return null; }
             return rightmostNode(previousNode(el.parentNode));
         } else {
-            return rightmostNode(el.parentNode.childNodes[i-1])
+            return rightmostNode(el.parentNode.childNodes[i-1]);
         }
     };
 
@@ -162,5 +162,22 @@ define([], function () {
         }
     };
 
+    var orderOfNodes = tree.orderOfNodes = function (a, b, root) {
+        // b might not be supplied
+        if (!b) { return; }
+        // a and b might be the same element
+        if (a === b) { return 0; }
+
+        var cur = b;
+        while (cur) {
+            cur = previousNode(cur, root);
+            // if you find 'a' while traversing backwards
+            // they are in the expected order
+            if (cur === a) { return 1; }
+        }
+        // otherwise 
+        return -1;
+    };
+
     return tree;
 });