Investigate: Call to a member function `get_token()` on null

Describe the bug This issue was reported in the WP.org forums: https://wordpress.org/support/topic/call-to-a-member-function-get_token-on-null

The merchant provided the following stacktrace:

[27-Sep-2024 17:05:20 UTC] PHP Fatal error:  Uncaught Error: Call to a member function get_token() on null in /opt/horrifiq/public_html/wp-content/plugins/woocommerce-gateway-stripe/includes/payment-methods/class-wc-stripe-upe-payment-gateway.php:969
Stack trace:
#0 /opt/horrifiq/public_html/wp-content/plugins/woocommerce-gateway-stripe/includes/payment-methods/class-wc-stripe-upe-payment-gateway.php(1449): WC_Stripe_UPE_Payment_Gateway->process_payment_with_saved_payment_method()
#1 /opt/horrifiq/public_html/wp-content/plugins/woocommerce-gateway-stripe/includes/class-wc-gateway-stripe.php(459): WC_Stripe_UPE_Payment_Gateway->retry_after_error()
#2 /opt/horrifiq/public_html/wp-content/plugins/woocommerce-gateway-stripe/includes/payment-methods/class-wc-stripe-upe-payment-gateway.php(733): WC_Gateway_Stripe->process_payment()
#3 /opt/horrifiq/public_html/wp-content/plugins/woocommerce/includes/class-wc-checkout.php(1062): WC_Stripe_UPE_Payment_Gateway->process_payment()
#4 /opt/horrifiq/public_html/wp-content/plugins/woocommerce/includes/class-wc-checkout.php(1293): WC_Checkout->process_order_payment()
#5 /opt/horrifiq/public_html/wp-content/plugins/woocommerce-gateway-stripe/includes/payment-methods/class-wc-stripe-payment-request.php(1702): WC_Checkout->process_checkout()
#6 /opt/horrifiq/public_html/wp-includes/class-wp-hook.php(324): WC_Stripe_Payment_Request->ajax_create_order()
#7 /opt/horrifiq/public_html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters()
#8 /opt/horrifiq/public_html/wp-includes/plugin.php(517): WP_Hook->do_action()
#9 /opt/horrifiq/public_html/wp-content/plugins/woocommerce/includes/class-wc-ajax.php(96): do_action()
#10 /opt/horrifiq/public_html/wp-includes/class-wp-hook.php(324): WC_AJAX::do_wc_ajax()
#11 /opt/horrifiq/public_html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters()
#12 /opt/horrifiq/public_html/wp-includes/plugin.php(517): WP_Hook->do_action()
#13 /opt/horrifiq/public_html/wp-includes/template-loader.php(13): do_action()
#14 /opt/horrifiq/public_html/wp-blog-header.php(19): require_once('/home/816423.cl...')
#15 /opt/horrifiq/public_html/index.php(17): require('/home/816423.cl...')
#16 {main}
  thrown in /opt/horrifiq/public_html/wp-content/plugins/woocommerce-gateway-stripe/includes/payment-methods/class-wc-stripe-upe-payment-gateway.php on line 969

From the stacktrace, this issue seems to be coming from customers using Google Pay/Apple Pay buttons where creating the payment intent returns an error. This then leads to us calling $this->retry_after_error() from within WC_Gateway_Stripe->process_payment() which then incorrectly call process_payment_with_saved_payment_method without a token in POST.

It looks like this only impacts intents created during Apple Pay/Google Pay requests, so I believe this will be fixed by ECE but I'm opening this issue to make sure this fatal error isn't possible.

To Reproduce

I haven't been able to reproduce this

Expected behavior

Don't call process_payment_with_saved_payment_method() when an retrying an error from creating an intent with Apple Pay/Google Pay payemnts.

Screenshots If applicable, add screenshots to help explain your problem.

Environment (please complete the following information):

WordPress Version
WooCommerce Version
Stripe Plugin Version
Browser [e.g. chrome, safari] and Version
Any other plugins installed

Additional context Add any other context about the problem here.

woocommerce / woocommerce-gateway-stripe

Investigate: Call to a member function `get_token()` on null #3503