Pass one installment at a time to dispatcher classes

app/services/solidus_subscriptions/checkout.rb

@@ -15,15 +15,15 @@ def process
         populate_order(order)
         finalize_order(order)
 
-        SolidusSubscriptions.configuration.success_dispatcher_class.new([installment], order).dispatch
+        SolidusSubscriptions.configuration.success_dispatcher_class.new(installment, order).dispatch
       rescue StateMachines::InvalidTransition
         if order.payments.any?(&:failed?)
-          SolidusSubscriptions.configuration.payment_failed_dispatcher_class.new([installment], order).dispatch
+          SolidusSubscriptions.configuration.payment_failed_dispatcher_class.new(installment, order).dispatch
         else
-          SolidusSubscriptions.configuration.failure_dispatcher_class.new([installment], order).dispatch
+          SolidusSubscriptions.configuration.failure_dispatcher_class.new(installment, order).dispatch
         end
       rescue ::Spree::Order::InsufficientStock
-        SolidusSubscriptions.configuration.out_of_stock_dispatcher_class.new([installment], order).dispatch
+        SolidusSubscriptions.configuration.out_of_stock_dispatcher_class.new(installment, order).dispatch
       end
 
       order

app/services/solidus_subscriptions/dispatcher/base.rb

@@ -3,17 +3,10 @@
 module SolidusSubscriptions
   module Dispatcher
     class Base
-      attr_reader :installments, :order
+      attr_reader :installment, :order
 
-      # Returns a new instance of this dispatcher.
-      #
-      # @param installments [Array<SolidusSubscriptions::Installment>] The installments to process
-      #   with this dispatcher
-      # @param order [Spree::Order] The order that was generated as a result of these installments
-      #
-      # @return [SolidusSubscriptions::Dispatcher]
-      def initialize(installments, order = nil)
-        @installments = installments
+      def initialize(installment, order)
+        @installment = installment
         @order = order
       end
 

app/services/solidus_subscriptions/dispatcher/failure_dispatcher.rb

@@ -1,15 +1,12 @@
 # frozen_string_literal: true
 
-# Handles failed installments.
 module SolidusSubscriptions
   module Dispatcher
     class FailureDispatcher < Base
       def dispatch
         order.touch(:completed_at)
         order.cancel
-        installments.each do |installment|
-          installment.failed!(order)
-        end
+        installment.failed!(order)
       end
     end
   end

app/services/solidus_subscriptions/dispatcher/out_of_stock_dispatcher.rb

@@ -1,11 +1,10 @@
 # frozen_string_literal: true
 
-# Handles installments that cannot be processed for lack of stock.
 module SolidusSubscriptions
   module Dispatcher
     class OutOfStockDispatcher < Base
       def dispatch
-        installments.each(&:out_of_stock)
+        installment.out_of_stock
       end
     end
   end

app/services/solidus_subscriptions/dispatcher/payment_failed_dispatcher.rb

@@ -1,19 +1,16 @@
 # frozen_string_literal: true
 
-# Handles payment failures for subscription installments.
 module SolidusSubscriptions
   module Dispatcher
     class PaymentFailedDispatcher < Base
       def dispatch
         order.touch(:completed_at)
         order.cancel
-        installments.each do |installment|
-          installment.payment_failed!(order)
-        end
+        installment.payment_failed!(order)
 
         ::Spree::Event.fire(
-          'solidus_subscriptions.installments_failed_payment',
-          installments: installments,
+          'solidus_subscriptions.installment_failed_payment',
+          installment: installment,
           order: order,
         )
       end

app/services/solidus_subscriptions/dispatcher/success_dispatcher.rb

@@ -1,17 +1,14 @@
 # frozen_string_literal: true
 
-# Handles installments that are processed successfully.
 module SolidusSubscriptions
   module Dispatcher
     class SuccessDispatcher < Base
       def dispatch
-        installments.each do |installment|
-          installment.success!(order)
-        end
+        installment.success!(order)
 
         ::Spree::Event.fire(
-          'solidus_subscriptions.installments_succeeded',
-          installments: installments,
+          'solidus_subscriptions.installment_processed',
+          installment: installment,
           order: order,
         )
       end

app/subscribers/solidus_subscriptions/churn_buster_subscriber.rb

@@ -6,8 +6,8 @@ module ChurnBusterSubscriber
 
     event_action :report_subscription_cancellation, event_name: 'solidus_subscriptions.subscription_canceled'
     event_action :report_subscription_ending, event_name: 'solidus_subscriptions.subscription_ended'
-    event_action :report_payment_success, event_name: 'solidus_subscriptions.installments_succeeded'
-    event_action :report_payment_failure, event_name: 'solidus_subscriptions.installments_failed_payment'
+    event_action :report_payment_success, event_name: 'solidus_subscriptions.installment_succeeded'
+    event_action :report_payment_failure, event_name: 'solidus_subscriptions.installment_failed_payment'
     event_action :report_payment_method_change, event_name: 'solidus_subscriptions.subscription_payment_method_changed'
 
     def report_subscription_cancellation(event)

spec/services/solidus_subscriptions/checkout_spec.rb

@@ -105,7 +105,7 @@
   def stub_dispatcher(klass, installment)
     instance_spy(klass).tap do |dispatcher|
       allow(klass).to receive(:new).with(
-        [installment],
+        installment,
         an_instance_of(Spree::Order)
       ).and_return(dispatcher)
     end

spec/subscribers/solidus_subscriptions/churn_buster_subscriber_spec.rb

@@ -29,10 +29,10 @@
       allow(SolidusSubscriptions).to receive(:churn_buster).and_return(churn_buster)
 
       order = build_stubbed(:order)
-      installments = build_list(:installment, 2)
+      installment = build_stubbed(:installment)
       Spree::Event.fire(
-        'solidus_subscriptions.installments_succeeded',
-        installments: installments,
+        'solidus_subscriptions.installment_succeeded',
+        installment: installment,
         order: order,
       )
 
@@ -46,10 +46,10 @@
       allow(SolidusSubscriptions).to receive(:churn_buster).and_return(churn_buster)
 
       order = build_stubbed(:order)
-      installments = build_list(:installment, 2)
+      installment = build_stubbed(:installment)
       Spree::Event.fire(
-        'solidus_subscriptions.installments_failed_payment',
-        installments: installments,
+        'solidus_subscriptions.installment_failed_payment',
+        installment: installment,
         order: order,
       )