With UPE enabled, customers are being charged multiple times for renewal order

[james-allan]

Describe the bug

On the latest version of WC Payments (5.5 - released last week), subscription customers are being charged multiple times for renewal orders.

The cause of this was introduced in this PR:

• POC: Multiple instances of single-method UPE at checkout #3968

As part of that PR, multiple instances of the payment method classes (eg CC_Payment_Gateway) are instantiated in each request. Those payment method classes extend WC_Payment_Gateway_WCPay and call that base class constructor. That class hierarchy leads to multiple calls of $this->maybe_init_subscriptions() which hooks onto the 'woocommerce_scheduled_subscription_payment_' . $this->id hook each time (code ref).

For as many 'woocommerce_scheduled_subscription_payment_' . $this->id functions that are hooked on, there are that many charge requests for renewal orders. For example, with legacy UPE this was 2 (CC + UPE). But with UPE SPlit enabled there were like 8 renewal order charges (CC + all the UPE ones).

To Reproduce

1. Enable WC Payments 5.5.0
   2.Enable UPE.
2. Enable the WC Subscriptions extension.
   3. Optional. Create a subscription product if you don't have one.
3. Purchase the subscription.
4. Go to the edit subscription screen and from the actions drop down, process a renewal order. (see screenshot below).
5. Go to your Stripe dashboard and the transaction list.
6. Note there are 2 or more charges for the same renewal order ID.

Admin Process renewal action.

Actual behavior

For every payment method class that extends the WC_Payment_Gateway_WCPay class, there's a $this->maybe_init_subscriptions() call and that leads to multiple instances WC Payments hooking onto woocommerce_scheduled_subscription_payment_.

For each one of those functions hooked onto that hook, there's a renewal charge being processed.

Screenshots

Duplicate charges.

Expected behavior

A customer should only be charged once for each renewal order.

[csmcneill]

Affected merchants so far:

• 5997330-zen
• 5993042-zen
• 5995326-zen
• 5988005-zen

[ryanr14]

5996496-zen

[rashedripon]

41069772-hc

[shevene]

5992705-zen

[Mxchael]

5996940-zen

[thisissandip]

41098166-hc

[thisissandip]

36540221-hc
41098883-hc

[thisissandip]

6000842-zen

[francoishvz]

40957388-hc

[seanbelly]

5999165-zd-woothemes

[csmcneill]

37442085-hc

[sarbouw]

6003016-zen

[shaunkuschel]

6003901-zen
40296706-hc

[francoishvz]

40471767-hc

[francoishvz]

41142097-hc

[c-shultz]

This has been addressed by #5625 which released in the 5.5.1 patch.