Handle bad interval for cron schedule

[westonruter]

Trac ticket: https://core.trac.wordpress.org/ticket/64404

---

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[westonruter]

This will be true when the $interval is false. I'm not sure if that is desirable or not.

[peterwilsoncc]

When this function eventually falls through to wp_schedule_event() the following code is run:

wordpress-develop/src/wp-includes/cron.php

Lines 235 to 245 in 8b0250c

	// Make sure timestamp is a positive integer.
	if ( ! is_numeric( $timestamp ) || $timestamp <= 0 ) {
	if ( $wp_error ) {
	return new WP_Error(
	'invalid_timestamp',
	__( 'Event timestamp must be a valid Unix timestamp.' )
	);
	}
	return false;
	}

This will change the behavior if the interval has been changed to false in wp_get_schedules() in an attempt to prevent the rescheduling of events so is probably undesirable.

[westonruter]

Maybe the $recurrence should be included here as well?

[peterwilsoncc]

I think this would be good if a named schedule is used, ie if the code doesn't fall back to

wordpress-develop/src/wp-includes/cron.php

Lines 361 to 368 in 8b0250c

	// Now we try to get it from the saved interval in case the schedule disappears.
	if ( 0 === $interval ) {
	$scheduled_event = wp_get_scheduled_event( $hook, $args, $timestamp );
	if ( $scheduled_event && isset( $scheduled_event->interval ) ) {
	$interval = $scheduled_event->interval;
	}
	}

[peterwilsoncc]

I've added a few notes inline.

[peterwilsoncc]

When this function eventually falls through to wp_schedule_event() the following code is run:

wordpress-develop/src/wp-includes/cron.php

Lines 235 to 245 in 8b0250c

	// Make sure timestamp is a positive integer.
	if ( ! is_numeric( $timestamp ) || $timestamp <= 0 ) {
	if ( $wp_error ) {
	return new WP_Error(
	'invalid_timestamp',
	__( 'Event timestamp must be a valid Unix timestamp.' )
	);
	}
	return false;
	}

This will change the behavior if the interval has been changed to false in wp_get_schedules() in an attempt to prevent the rescheduling of events so is probably undesirable.

[peterwilsoncc]

Suggested change

	if ( ! is_int( $interval ) || $interval <= 0 ) {
	if ( ! is_numeric( $interval ) || $interval <= 0 ) {

Matches the behaivour of the existing check in wp_schedule_event()

[peterwilsoncc]

I think this would be good if a named schedule is used, ie if the code doesn't fall back to

wordpress-develop/src/wp-includes/cron.php

Lines 361 to 368 in 8b0250c

	// Now we try to get it from the saved interval in case the schedule disappears.
	if ( 0 === $interval ) {
	$scheduled_event = wp_get_scheduled_event( $hook, $args, $timestamp );
	if ( $scheduled_event && isset( $scheduled_event->interval ) ) {
	$interval = $scheduled_event->interval;
	}
	}