<?php

final class ChildClass extends VendorClass
{
    private bool $executed;
    
    public function run(): void
    {
        $this->executed = false;
        
        parent::run();
        
        if (!$this->executed) {
            echo 'not run';
        }
    }
    
    protected function execute(): void
    {
        $this->executed = true;
        
        parent::run();
    }
}

class VendorClass
{
    public function run()
    {
        $this->execute();
    }
    protected function execute()
    {
    }
}

(new ChildClass)->run();