Error after upgrading to PHP 8.0

[michaelbeil]

Describe the bug
A customer (ticket 447938) ran into this error after upgrading to PHP 8.0:

Warning: Undefined array key “edit” in /usr/www/users/x/y.x.com/wp-content/plugins/pmpro-auto-renewal-checkbox/pmpro-auto-renewal-checkbox.php on line 38

To Reproduce
Steps to reproduce the behavior on customer site:

1. Activate Paid Memberships Pro, and Auto-Renewal Checkbox Add On
2. Set PHP version to PHP 8.0 or higher, see the following error on the main (paid) checkout page:

Warning: Undefined array key “edit” in /usr/www/users/x/y.x.com/wp-content/plugins/pmpro-auto-renewal-checkbox/pmpro-auto-renewal-checkbox.php on line 38

Expected behavior
There should not be an error.

Isolating the problem:

• Deactivated other plugins and confirmed this bug occurs when only Paid Memberships Pro, and Auto-Renewal Checkbox Add On is active.
• This bug happens with a default WordPress theme active, or Memberlite.
• Reproduce this bug consistently using the steps above.

This came up in ticket 441951, but I have not been able to replicate this.

WordPress Environment

Paid Memberships Pro 2.9.5, Auto-Renewal Checkbox 0.3.0, WordPress 6.0.2, PHP 8.0.22

[ipokkel]

Another fatal error was encountered while running PHP8 (8.1.9)

An error of type E_ERROR was caused in line 127 of the file /wp-content/plugins/pmpro-auto-renewal-checkbox/includes/cancel-on-next-payment-date.php. Error message: Uncaught TypeError: date(): Argument #2 ($timestamp) must be of type ?int, string given.

pmpro-auto-renewal-checkbox/includes/cancel-on-next-payment-date.php

Line 127 in 18ddc90

$expiration_date = date( 'Y-m-d H:i:s', $pmpro_next_payment_timestamp );

To Reproduce

1. Activate Paid Memberships Pro, and Auto-Renewal Checkbox Add On
2. Set the PHP version to PHP 8.1.9 or higher
3. Navigate to Users > All Users
4. Select a user(s) that belongs to a recurring payment subscription.
5. Select Delete from the Bulk Actions drop-down and click on Apply button
6. Check both Cancel any related membership levels first. This may trigger cancellations at the gateway or other third party services and Delete any related membership history. Order history will be retained options
7. Confirm Deletion
8. See error.

[JarrydLong]

@ipokkel and I have tested this again but haven't been able to consistently replicate the issue.

We'll keep an eye on this and apply a fix when we can replicate the issue consistently.

[britwylie]

Similar error?

[error] 2699860#2699860: *467369 FastCGI sent in stderr: "PHP message: PHP Fatal error: Uncaught TypeError: date(): Argument #2 ($timestamp) must be of type ?int, string given in /var/www/sitename.com/wp-content/plugins/paid-memberships-pro/classes/gateways/class.pmprogateway_paypalexpress.php:829

PHP version 8.3
User checkout in Paypal, with or without recurring payments.
On "complete payment" redirect, transaction fails.
Wordpress and PMPro updated today.