Replaces "instanceof Node" in favor of NodeTrait::hasTrait()

Author: David DiMaria

src/Collection.php

@@ -77,7 +77,9 @@ public function toTree($root = null)
      */
     protected function getRootNodeId($root = null)
     {
-        if ($root instanceof Node) return $root->getKey();
+        if (NodeTrait::hasTrait($root)) {
+            return $root->getKey();
+        }
 
         // If root node is not specified we take parent id of node with
         // least lft value as root node id.

src/QueryBuilder.php

@@ -84,7 +84,7 @@ public function whereAncestorOf($id)
 
         $key = $this->query->getGrammar()->wrap($keyName);
 
-        if ($id instanceof Node)
+        if (NodeTrait::hasTrait($id))
         {
             $dataSource = '?';
 
@@ -167,7 +167,7 @@ public function orWhereNodeBetween($values)
      */
     public function whereDescendantOf($id, $boolean = 'and', $not = false)
     {
-        if ($id instanceof Node)
+        if (NodeTrait::hasTrait($id))
         {
             $data = $id->getBounds();
         }