fix

lib/entity/nullentity.php

@@ -0,0 +1,19 @@
+<?php
+
+
+namespace Bx\Null\Entity;
+
+
+use Bx\Null\IFields\NullFields;
+use Wt\Core\Supports\Entity;
+
+class NullEntity extends Entity
+{
+    /**
+     * @return NullFields
+     */
+    public function fields()
+    {
+        return parent::fields();
+    }
+}