RecursiveIteratorIterator offsetSet Example

function test_set_values() {
        $data = [
            'test' => 'value',
            'level_one' => [
                'level_two' => [
                    'level_three' => [
                        'replace_this_array' => [
                            'key_one' => 'testing',
                            'key_two' => 'value',
                            'special_key' => 'replacement_value',
                            'four' => 'another value'
                        ]
                    ],
                    'ordinary_key' => 'value'
                ]
            ]
        ];

        $arrObject = json_decode( json_encode( $data ) );
        $completeIterator = new RecursiveIteratorIterator( new RecursiveArrayIterator( $arrObject ), RecursiveIteratorIterator::SELF_FIRST );

        foreach ( $completeIterator as $key => $value ) {
            if ( property_exists( $value, 'special_key' ) ) {
                $replaced_array = array_fill( 0, count( ( array ) $value ), $value->special_key );
                $combined_array = array_combine( array_keys( ( array ) $value ), array_values( $replaced_array ) );
                $combined_array['profession'] = 'Programmer';
                $current_depth = $completeIterator->getDepth();
                for ( $subDepth = $current_depth; $subDepth >= 0; $subDepth-- ) {
                    $subIterator = $completeIterator->getSubIterator( $subDepth );

                    // If we are on the level we want to change, use the replacements ($value) 
                    // other wise set the key to the parent iterators value
                    if ( $subDepth === $current_depth ) {
                        $newVal = ( object ) $combined_array;
                    } else {
                        $newVal = $completeIterator->getSubIterator( $subDepth + 1 )->getArrayCopy();
                    }
                    $subIterator->offsetSet( $subIterator->key(), $newVal );
                }
            }
        }

        print_r( $arrObject );
    }