Doc #77202 [Opn->Csd]: DateInterval compare unpredictable result

Edit report at https://bugs.php.net/bug.php?id=77202&edit=1

 ID:                 77202
 Updated by:         [email protected]
 Reported by:        thomas dot wanka at gmx dot net
 Summary:            DateInterval compare unpredictable result
-Status:             Open
+Status:             Closed
 Type:               Documentation Problem
 Package:            Date/time related
 Operating System:   Linux
 PHP Version:        7.2.12
-Assigned To:        
+Assigned To:        derick
 Block user comment: N
 Private report:     N

 New Comment:

Thank you for your bug report. This issue has already been fixed
in the latest released version of PHP, which you can download at
http://www.php.net/downloads.php

This was addressed in PHP 7.4, where the script (After fixing syntax), now shows:

Warning: Cannot compare DateInterval objects in Standard input code on line 11


Previous Comments:
------------------------------------------------------------------------
[2018-12-04 23:04:14] a at b dot c dot de

See also Bug #74940

------------------------------------------------------------------------
[2018-11-26 11:23:37] a at b dot c dot de

Where did you read that > could be used to compare objects in the first place?



What does happen is that if you do a debugging dump of a DateTime object it creates a bunch of additional properties.
<?php
$old = DateTime::createFromFormat('Y-m-d H:i:s', '2018-11-26 09:29:00'); 
$now = new DateTime('now',new DateTimeZone('Europe/Berlin'));
$actualDiff = $now->diff($old);

echo "Weekday: ", $actualDiff->weekday;
echo "\n";
print_r($actualDiff);
echo "\n";
echo "Weekday: ", $actualDiff->weekday;

------------------------------------------------------------------------
[2018-11-26 08:53:54] thomas dot wanka at gmx dot net

Description:
------------
The result if compare operator on two DateInterval objects is unpredictable.
See code in the "test script" section:
the result of the if() statement depends on the code before. If, for instance, you print the DateInterval, the internal structure seems to change, and the result is correct. Otherwise, the result is not correct. The system should output an error or a warning if the compare operater is not fully implemented.

Test script:
---------------
<?php
$old = DateTime::createFromFormat('Y-m-d H:i:s', '2018-11-26 09:29:00'); 
// constant here for demo only, i read datetime field from database
$now = new DateTime('now',new DateTimeZone('Europe/Berlin'));
$maxdiff = new DateInterval('PT30M');
$actualDiff = $now->diff($old);

// echo "<pre>"; print_r($now); echo "</pre><br />";
// echo "<pre>"; print_r($maxdiff ); echo "</pre><br />";

if ($actualDiff>$maxDiff) echo "time is up" else echo "just wait";
?>


Expected result:
----------------
throw an error if an nvalid operator ist used 
minimum request: add information about this behauviour into documentation of DateInterval

Actual result:
--------------
operator is performed, result is unpredictable


------------------------------------------------------------------------



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Edit this bug report at https://bugs.php.net/bug.php?id=77202&edit=1