feat(wavl): refactor fixDelete

Signed-off-by: Matej Focko <mfocko@redhat.com>

wavl.js

@@ -20,7 +20,7 @@ class WAVLTree extends AVLTree {
         );
     }
 
-    fixDelete(x, y, z, reversed, rotateLeft, rotateRight) {
+    fixDelete(x, y, z, reversed, rotatingAroundRoot, rotateLeft, rotateRight) {
         let newRoot = x;
         let [v, w] = [y.left, y.right];
 
@@ -32,23 +32,40 @@ class WAVLTree extends AVLTree {
 
         if (wDiff == 1 && y.parent) {
             newRoot = rotateLeft(y.parent);
+            if (rotatingAroundRoot) {
+                this.root = newRoot;
+            }
+            this.record();
 
             y.promote();
+            this.record();
+
             z.demote();
+            this.record();
 
             if (z.type() == LEAF) {
                 z.demote();
+                this.record();
             }
         } else if (wDiff == 2 && v && v.parent) {
             rotateRight(v.parent);
+            this.record();
+
             newRoot = rotateLeft(v.parent);
+            if (rotatingAroundRoot) {
+                this.root = newRoot;
+            }
+            this.record();
 
             v.promote().promote();
-            y.demote();
+            this.record();
-            z.demote().demote();
-        }
 
-        return newRoot;
+            y.demote();
+            this.record();
+
+            z.demote().demote();
+            this.record();
+        }
     }
 
     bottomUpDelete(x, parent) {
@@ -67,8 +84,11 @@ class WAVLTree extends AVLTree {
             (yDiff == 2 || nodeDifferences(y).equals([2, 2]))
         ) {
             parent.demote();
+            this.record();
+
             if (yDiff != 2) {
                 y.demote();
+                this.record();
             }
 
             x = parent;
@@ -88,34 +108,31 @@ class WAVLTree extends AVLTree {
         }
 
         let rotatingAroundRoot = parent.parent == null;
-        let newRoot = parent;
 
         let parentNodeDiffs = nodeDifferences(parent);
         if (parentNodeDiffs.sort().equals([1, 3])) {
             if (parent.left === x) {
-                newRoot = this.fixDelete(
+                this.fixDelete(
                     x,
                     parent.right,
                     parent,
                     false,
+                    rotatingAroundRoot,
                     rotateLeft,
                     rotateRight
                 );
             } else {
-                newRoot = this.fixDelete(
+                this.fixDelete(
                     x,
                     parent.left,
                     parent,
                     true,
+                    rotatingAroundRoot,
                     rotateRight,
                     rotateLeft
                 );
             }
         }
-
-        if (rotatingAroundRoot) {
-            this.root = newRoot;
-        }
     }
 
     deleteFixup(y, parent) {
@@ -123,6 +140,7 @@ class WAVLTree extends AVLTree {
 
         if (nodeDifferences(z).equals([2, 2])) {
             z.demote();
+            this.record();
         }
 
         if (!parent) {