1) Create a php file
<?php

namespace TestA\TestB\TestC;

class A
{
private $items;

public function __construct()
{
    $this->items = array("\x0" => 1);
}

}

class B extends A {
public function foo() {
echo 1; // Set breakpoint here and inspect $items
}
}

(new B())->foo();

2) Put breakpoint inside 'foo' method and start debugging.

3) Call 'property_get' command for 'TestA\TestB\TestC\Aitems'.
<- property_get -i 20 -n $this->TestA\TestB\TestC\Aitems -d 0 -c 0 -p 0

Result:
<property name="$this->TestA\TestB\TestC\Aitems" fullname="$this->TestA\TestB\TestC\Aitems" type="array" children="1" numchildren="1" page="0" pagesize="100">
<property type="int">
<name encoding="base64"><![CDATA[AA==]]></name>
<fullname encoding="base64"><![CDATA[JHRoaXMtPipUZXN0QVxcVGVzdEJcXFRlc3RDXFxBKml0ZW1zWyIAIl0=]]></fullname><value encoding="base64"><![CDATA[MQ==]]></value>
</property>

Where fullname decodes in "$this->TestA\TestB\TestC\Aitems["\x0"]"