<?php
 
function invokeWithReference(StdClass &$class)
{
    // Create args array using reference
    $args = [$class];
    $obj = new ReflectionClass('xyz');
    return $obj->newInstanceArgs($args);
}
 
class xyz
{
    public $class;
 
    public function __construct(StdClass $class)
    {
        $this->class = $class;
    }
 
    public function setTest2()
    {
        $this->class->test2 = 'goodbye';
    }
}
 
$class = new StdClass;
$instance = invokeWithReference($class);
 
$class->test = 'hello';
$instance->setTest2();
 
echo $instance->class->test;
echo PHP_EOL;
echo $class->test2;

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