Gets inherited permissions working, adds lots of unit tests, few more tests to write now.

src/Umbraco.Core/StringExtensions.cs

@@ -41,6 +41,22 @@ namespace Umbraco.Core
                 ToCSharpEscapeChars[escape[0]] = escape[1];
         }
 
+        /// <summary>
+        /// Convert a path to node ids in the order from right to left (deepest to shallowest)
+        /// </summary>
+        /// <param name="path"></param>
+        /// <returns></returns>
+        internal static int[] GetIdsFromPathReversed(this string path)
+        {
+            var nodeIds = path.Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries)
+                .Select(x => x.TryConvertTo<int>())
+                .Where(x => x.Success)
+                .Select(x => x.Result)
+                .Reverse()
+                .ToArray();
+            return nodeIds;
+        }
+
         /// <summary>
         /// Removes new lines and tabs
         /// </summary>