Show subscription payments that are not linked to a period

[remcotolsma]

At the moment, payments that are connected to a subscription, but not to a specific subscription period, will not be shown with a subscription. This may, for example, concern a payment of €0.01 for a payment method/mandate change. But also WooCommerce Subscriptions renewal payments are no longer linked to a specific subscription period.

wp-pay-core/views/meta-box-subscription-payments.php

Line 22 in 6308ab6

$periods = $subscription->get_payments_by_period();

wp-pay-core/src/Subscriptions/Subscription.php

Lines 333 to 390 in 6308ab6

	/**
	* Get payments by period.
	*
	* @return array
	*/
	public function get_payments_by_period() {
	$payments = $this->get_payments();
	$periods = [];
	foreach ( $payments as $payment ) {
	// Get period for this subscription.
	$period = null;
	$payment_periods = $payment->get_periods();
	if ( null === $payment_periods ) {
	continue;
	}
	foreach ( $payment_periods as $period ) {
	if ( $this->get_id() === $period->get_phase()->get_subscription()->get_id() ) {
	break;
	}
	}
	if ( null === $period ) {
	continue;
	}
	// Add period to result.
	$start = $period->get_start_date()->getTimestamp();
	if ( ! \array_key_exists( $start, $periods ) ) {
	$periods[ $start ] = [
	'period' => $period,
	'payments' => [],
	'can_retry' => true,
	];
	}
	// Add payment to result.
	$periods[ $start ]['payments'][ $payment->get_date()->getTimestamp() ] = $payment;
	if ( \in_array( $payment->get_status(), [ PaymentStatus::OPEN, PaymentStatus::SUCCESS ], true ) ) {
	$periods[ $start ]['can_retry'] = false;
	}
	}
	// Sort periods and payments.
	\krsort( $periods );
	foreach ( $periods as &$period ) {
	\ksort( $period['payments'] );
	}
	return $periods;
	}

These periodless payments should be shown with subscriptions.

1. Payments without period are not listed in the subscription payments meta box.

Originally posted by @rvdsteege in pronamic/wp-pronamic-pay-woocommerce#40 (review)

A little bit related:

• Introduce public subscription view page for cancel, renew and mandate actions wp-pronamic-pay#201