var_dump includes non-existing (but somehow existing?) properties

[kkmuffme]

Description

I was using tideways PHP https://tideways.com/profiler/downloads "Span" https://support.tideways.com/documentation/reference/php-extension/custom-timespans.html
For some reason var_dump shows that the object has public properties, but upon accessing them, it fails, since these properties are not actually public.
property_exists() also returns false on it

ReflectionProperty also fails

ReflectionException: Property Tideways\Profiler\Span::$start does not exist

Which would mean it doesn't exist at all, neither privately nor publically.
Not sure what is going on here

The following code:

<?php
$span = \Tideways\Profiler::createSpan('other text');
$span->annotate(
	array(
		'title' => 'some text',
	)
);
var_dump($span);
var_dump(property_exists($span, 'start'));
var_dump($span->start);

https://support.tideways.com/documentation/reference/php-extension/custom-timespans.html

Resulted in this output:

object(Tideways\Profiler\Span)#2495 (6) {
  ["s"] => string(16) "redacted1"
  ["p"] => string(16) "redacted2"
  ["t"] => string(16) "redacted2"
  ["start"] => int(1731425730246)
  ["n"] => string(6) "custom"
  ["a"] => array(2) {
    ["title"] => string(6) "some text"
    ["custom_type"] => string(11) "other text"
  }
}
bool(false)
NULL

But I expected this output instead: (actually this is wrong too, since it's not "private" either, since ReflectionProperty fails. Not sure what is going on here)

object(Tideways\Profiler\Span)#2495 (6) {
  ["s":"Tideways\Profiler\Span":private] => string(16) "redacted1"
  ["p":"Tideways\Profiler\Span":private] => string(16) "redacted2"
  ["t":"Tideways\Profiler\Span":private] => string(16) "redacted2"
  ["start":"Tideways\Profiler\Span":private] => int(1731425730246)
  ["n":"Tideways\Profiler\Span":private] => string(6) "custom"
  ["a":"Tideways\Profiler\Span":private] => array(2) {
    ["title"] => string(6) "some text"
    ["custom_type"] => string(11) "other text"
  }
}
bool(false)
NULL

PHP Version

8.3

Operating System

No response

[cmb69]

Well, don't know about that extension (consider to ask Tideways), but I would assume that these properties are implemented similar to DateTime properties (see https://3v4l.org/Y684E). That is certainly not a bug in var_dump() or property_exists(), but rather a limitation of the extension.

[iluuu1994]

Please contact Tideways. I'm not sure the extension is even open-source. There is not evident bug on PHPs side.