Added root ids.

src/data/mod.rs

@@ -15,6 +15,7 @@ struct IDPath {
 impl IDPath {
     fn new() -> Self {
         let mut path = Vec::new();
+        path.push(Uuid::nil());
         Self { path: path }
     }
 
@@ -24,7 +25,9 @@ impl IDPath {
 
     fn extend(&self, addition: Uuid) -> Self {
         let mut result = self.clone();
+        result.path.pop();
         result.path.push(addition);
+        result.path.push(Uuid::nil());
         result
     }
 
@@ -39,8 +42,9 @@ mod ids {
 
     #[test]
     fn create_idpath() {
+        let expected = [Uuid::nil()];
         let id = IDPath::new();
-        assert_eq!(id.path.len(), 0);
+        assert_eq!(id.path, expected);
     }
 
     #[test]
@@ -56,20 +60,18 @@ mod ids {
     #[test]
     fn extend_idpath() {
         let mut path: Vec<Uuid> = Vec::new();
+        path.push(Uuid::nil());
         let mut id = IDPath::new();
-        for _ in 1..5 {
+        for count in 1..5 {
+            assert_eq!(id.path.len(), count);
             let extended = IDPath::next();
             id = id.extend(extended.clone());
+            path.pop();
             path.push(extended);
+            path.push(Uuid::nil());
             assert_eq!(id.path, path);
         }
     }
-
-    #[test]
-    fn get_root() {
-        let mut id = IDPath::new();
-        id.root();
-    }
 }
 
 struct Cache {