[wp-trac] [WordPress Trac] #63987: wp_get_scheduled_event() incorrectly returns false for cron events scheduled with a timestamp of 0.

[WordPress Trac]

#63987: wp_get_scheduled_event() incorrectly returns false for cron events
scheduled with a timestamp of 0.
--------------------------+-----------------------------
 Reporter:  codekraft     |      Owner:  (none)
     Type:  defect (bug)  |     Status:  new
 Priority:  normal        |  Milestone:  Awaiting Review
Component:  Cron API      |    Version:  trunk
 Severity:  normal        |   Keywords:
  Focuses:                |
--------------------------+-----------------------------
 When using the wp_get_scheduled_event() function to retrieve a scheduled
 cron event, it incorrectly returns false if the event's timestamp is
 exactly 0 (the Unix epoch).

 wp_get_scheduled_event can be found in wp-includes/cron.php:787

 **The issue**

 The issue lies in this line:

 {{{#!php
 <?php
 if ( ! $timestamp ) {
 }}}


 In PHP, the integer 0 is evaluated as false in a boolean context. This
 causes the function to enter the "get next event" block, which then fails
 to find the event at timestamp 0 and ultimately returns false, despite the
 event existing in the cron array.

 **How to Reproduce**
 Schedule a cron event with a timestamp of 0. You can do this by manually
 adding it to the cron array or by using a function like this:

 {{{#!php
 <?php
 // Add an event with a timestamp of 0.
 // This is for demonstration purposes. In a real scenario, this might
 happen due to a bug in a plugin.
 $crons = _get_cron_array();
 $crons[0]['my_test_hook']['unique_key'] = array(
     'schedule' => false,
     'args'     => array(),
 );
 _set_cron_array($crons);
 }}}

 Attempt to retrieve this specific event using wp_get_scheduled_event()
 with the timestamp 0:

 {{{#!php
 <?php
 $event = wp_get_scheduled_event( 'my_test_hook', array(), 0 );
 }}}

 Check the result.

 {{{#!php
 <?php
 if ( false === $event ) {
     echo "The function returned false. This is the bug.";
 } else {
     echo "The function correctly found the event.";
 }
 }}}

 Expected behavior: The function should return the event object, as the
 event with a timestamp of 0 exists.

 Current behavior: The function returns false, indicating the event does
 not exist. So i cannot remove that event from the cron array using
 `wp_unschedule_event`

 **Suggested Fix**

 A possible fix is to change the if condition to be more explicit, for
 example:
 {{{#!php
 <?php
 if ( null === $timestamp ) {
 }}}

 This would only trigger the "get next event" logic when no timestamp is
 provided, correctly handling a timestamp of 0 as a valid value.

-- 
Ticket URL: <https://core.trac.wordpress.org/ticket/63987>
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