Fix updating parent max

Author: dan-on

src/IntervalTree.php

@@ -341,18 +341,14 @@ private function treeSearch(Node $node, Node $searchNode): ?Node
     private function treeSearchInterval(Node $searchNode, Node $fromNode = null): Iterator
     {
         $fromNode = $fromNode ?? $this->root;
-        $stack = [$fromNode];
-        while (!empty($stack)) {
-            $node = array_pop($stack);
-            if ($node->getLeft() !== $this->nilNode && !$node->notIntersectLeftSubtree($searchNode)) {
-                yield from $this->treeSearchInterval($searchNode, $node->getLeft());
-            }
-            if ($node->intersect($searchNode)) {
-                yield $node;
-            }
-            if ($node->getRight() !== $this->nilNode && !$node->notIntersectRightSubtree($searchNode)) {
-                yield from $this->treeSearchInterval($searchNode, $node->getRight());
-            }
+        if ($fromNode->getLeft() !== $this->nilNode && !$fromNode->notIntersectLeftSubtree($searchNode)) {
+            yield from $this->treeSearchInterval($searchNode, $fromNode->getLeft());
+        }
+        if ($fromNode->intersect($searchNode)) {
+            yield $fromNode;
+        }
+        if ($fromNode->getRight() !== $this->nilNode && !$fromNode->notIntersectRightSubtree($searchNode)) {
+            yield from $this->treeSearchInterval($searchNode, $fromNode->getRight());
         }
     }
 
@@ -445,7 +441,7 @@ private function rotateRight(Node $y): void
     /**
      * @return Iterator<Node>
      */
-    private function treeWalk(): Iterator
+    public function treeWalk(): Iterator
     {
         if ($this->root !== null) {
             $stack = [$this->root];

src/Node.php

@@ -132,6 +132,9 @@ public function updateMax(): void
         if ($this->getLeft()->max !== null) {
             $this->max = $this->max->merge($this->getLeft()->max);
         }
+        if ($this->getParent() !== null) {
+            $this->getParent()->updateMax();
+        }
     }
 
     public function notIntersectLeftSubtree(Node $searchNode): bool