From 9bcf0d5b38cade71e772167303e65bbdfc40d4b0 Mon Sep 17 00:00:00 2001
From: Matt-Yorkley <9029026+Matt-Yorkley@users.noreply.github.com>
Date: Fri, 11 Jun 2021 15:08:11 +0100
Subject: [PATCH 1/8] Handle Stripe payments when checkout fails due to stock
 issues

This can occur when stock is reduced after the user is redirected to Stripe and before they are redirected back. The stock is insufficient, the order is not complete, the user is bounced back to the cart, but a *pending* Stripe payment is left on the order.
---
 app/controllers/checkout_controller.rb | 20 +++++++++++++++++---
 config/locales/en.yml                  |  1 +
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/app/controllers/checkout_controller.rb b/app/controllers/checkout_controller.rb
index 13b6654782..37bdff3954 100644
--- a/app/controllers/checkout_controller.rb
+++ b/app/controllers/checkout_controller.rb
@@ -37,7 +37,7 @@ class CheckoutController < ::BaseController
     # This is only required because of spree_paypal_express. If we implement
     # a version of paypal that uses this controller, and more specifically
     # the #action_failed method, then we can remove this call
-    OrderCheckoutRestart.new(@order).call
+    reset_order_to_cart
   rescue Spree::Core::GatewayError => e
     rescue_from_spree_gateway_error(e)
   end
@@ -82,7 +82,7 @@ class CheckoutController < ::BaseController
     @order = current_order
 
     redirect_to(main_app.shop_path) && return if redirect_to_shop?
-    redirect_to_cart_path && return unless valid_order_line_items?
+    handle_invalid_stock && return unless valid_order_line_items?
 
     before_address
     setup_for_current_state
@@ -100,7 +100,10 @@ class CheckoutController < ::BaseController
         distributes_order_variants?(@order)
   end
 
-  def redirect_to_cart_path
+  def handle_invalid_stock
+    cancel_incomplete_payments if valid_payment_intent_provided?
+    reset_order_to_cart
+
     respond_to do |format|
       format.html do
         redirect_to main_app.cart_path
@@ -112,6 +115,17 @@ class CheckoutController < ::BaseController
     end
   end
 
+  def cancel_incomplete_payments
+    # The checkout could not complete due to stock running out. We void any pending (incomplete)
+    # Stripe payments here as the order will need to be changed and resubmitted (or abandoned).
+    @order.payments.pending.each(&:void!)
+    flash[:notice] = I18n.t("checkout.payment_cancelled_due_to_stock")
+  end
+
+  def reset_order_to_cart
+    OrderCheckoutRestart.new(@order).call
+  end
+
   def setup_for_current_state
     method_name = :"before_#{@order.state}"
     __send__(method_name) if respond_to?(method_name, true)
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 84140e72bc..76943a0815 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -1315,6 +1315,7 @@ en:
       message_html: "I agree to the seller's %{terms_and_conditions_link} and the platform %{tos_link}."
       terms_and_conditions: "Terms and Conditions"
     failed: "The checkout failed. Please let us know so that we can process your order."
+    payment_cancelled_due_to_stock: "Payment cancelled: the checkout could not be completed due to stock issues."
   shops:
     hubs:
       show_closed_shops: "Show closed shops"

From 2cd6b05abaddd00b9818213311aa30bf89ba6b09 Mon Sep 17 00:00:00 2001
From: Matt-Yorkley <9029026+Matt-Yorkley@users.noreply.github.com>
Date: Mon, 14 Jun 2021 19:51:09 +0100
Subject: [PATCH 2/8] Use Order::Contents service in test setup

---
 spec/controllers/checkout_controller_spec.rb | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/spec/controllers/checkout_controller_spec.rb b/spec/controllers/checkout_controller_spec.rb
index d1813fa16a..24d4ec6e91 100644
--- a/spec/controllers/checkout_controller_spec.rb
+++ b/spec/controllers/checkout_controller_spec.rb
@@ -49,8 +49,7 @@ describe CheckoutController, type: :controller do
     let(:shipping_method) { distributor.shipping_methods.first }
 
     before do
-      order.line_items << create(:line_item,
-                                 variant: order_cycle.variants_distributed_by(distributor).first)
+      order.contents.add(order_cycle.variants_distributed_by(distributor).first)
 
       allow(controller).to receive(:current_distributor).and_return(distributor)
       allow(controller).to receive(:current_order_cycle).and_return(order_cycle)

From a199f80ed40aaa5948f7596f96c230d8a33fae37 Mon Sep 17 00:00:00 2001
From: Matt-Yorkley <9029026+Matt-Yorkley@users.noreply.github.com>
Date: Mon, 14 Jun 2021 19:51:37 +0100
Subject: [PATCH 3/8] Add test for insufficient stock behavior after Stripe
 redirect

---
 spec/controllers/checkout_controller_spec.rb | 48 ++++++++++++++++----
 1 file changed, 38 insertions(+), 10 deletions(-)

diff --git a/spec/controllers/checkout_controller_spec.rb b/spec/controllers/checkout_controller_spec.rb
index 24d4ec6e91..bde41ddce5 100644
--- a/spec/controllers/checkout_controller_spec.rb
+++ b/spec/controllers/checkout_controller_spec.rb
@@ -91,19 +91,47 @@ describe CheckoutController, type: :controller do
       allow(OrderCycleDistributedVariants).to receive(:new).and_return(order_cycle_distributed_variants)
     end
 
-    it "redirects when some items are out of stock" do
-      allow(order).to receive_message_chain(:insufficient_stock_lines, :empty?).and_return false
+    context "running out of stock" do
+      it "redirects when some items are out of stock" do
+        allow(order).to receive_message_chain(:insufficient_stock_lines, :empty?).and_return false
 
-      get :edit
-      expect(response).to redirect_to cart_path
-    end
+        get :edit
+        expect(response).to redirect_to cart_path
+      end
 
-    it "redirects when some items are not available" do
-      allow(order).to receive_message_chain(:insufficient_stock_lines, :empty?).and_return true
-      expect(order_cycle_distributed_variants).to receive(:distributes_order_variants?).with(order).and_return(false)
+      it "redirects when some items are not available" do
+        allow(order).to receive_message_chain(:insufficient_stock_lines, :empty?).and_return true
+        expect(order_cycle_distributed_variants).to receive(:distributes_order_variants?).with(order).and_return(false)
 
-      get :edit
-      expect(response).to redirect_to cart_path
+        get :edit
+        expect(response).to redirect_to cart_path
+      end
+
+      context "after redirecting back from Stripe" do
+        let(:order) { create(:order_with_totals_and_distribution) }
+        let!(:payment) { create(:payment, state: "pending", amount: order.total, order: order) }
+
+        before do
+          allow(order).to receive_message_chain(:insufficient_stock_lines, :empty?).and_return(false)
+          allow(order_cycle_distributed_variants).to receive(:distributes_order_variants?).
+            with(order).and_return(true)
+          allow(controller).to receive(:valid_payment_intent_provided?) { true }
+          order.save
+          allow(order).to receive_message_chain(:payments, :completed) { [] }
+          allow(order).to receive_message_chain(:payments, :pending) { [payment] }
+        end
+
+        it "cancels the payment and resets the order to cart" do
+          expect(payment).to receive(:void!).and_call_original
+
+          spree_post :edit
+
+          expect(response).to redirect_to cart_path
+          expect(flash[:notice]).to eq I18n.t('checkout.payment_cancelled_due_to_stock')
+
+          expect(order.state).to eq "cart"
+        end
+      end
     end
 
     describe "when items are available and in stock" do

From b1db06a3c680ade300407cf40b405435a8245862 Mon Sep 17 00:00:00 2001
From: Matt-Yorkley <9029026+Matt-Yorkley@users.noreply.github.com>
Date: Fri, 9 Jul 2021 13:24:37 +0100
Subject: [PATCH 4/8] Allow payments in requires_authorization state to be
 voided

---
 app/models/spree/payment.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/app/models/spree/payment.rb b/app/models/spree/payment.rb
index 3bb4b60858..498c07577e 100644
--- a/app/models/spree/payment.rb
+++ b/app/models/spree/payment.rb
@@ -72,7 +72,7 @@ module Spree
         transition from: [:processing, :pending, :checkout, :requires_authorization], to: :completed
       end
       event :void do
-        transition from: [:pending, :completed, :checkout], to: :void
+        transition from: [:pending, :completed, :requires_authorization, :checkout], to: :void
       end
       # when the card brand isnt supported
       event :invalidate do

From b4a9a6fea5585021f2ba945d717230055f0e66c5 Mon Sep 17 00:00:00 2001
From: Matt-Yorkley <9029026+Matt-Yorkley@users.noreply.github.com>
Date: Fri, 9 Jul 2021 13:28:19 +0100
Subject: [PATCH 5/8] Add :incomplete scope in Spree::Payment

---
 app/models/spree/payment.rb | 1 +
 1 file changed, 1 insertion(+)

diff --git a/app/models/spree/payment.rb b/app/models/spree/payment.rb
index 498c07577e..b41e085cde 100644
--- a/app/models/spree/payment.rb
+++ b/app/models/spree/payment.rb
@@ -46,6 +46,7 @@ module Spree
     scope :from_credit_card, -> { where(source_type: 'Spree::CreditCard') }
     scope :with_state, ->(s) { where(state: s.to_s) }
     scope :completed, -> { with_state('completed') }
+    scope :incomplete, -> { where(state: %w(checkout pending requires_authorization)) }
     scope :pending, -> { with_state('pending') }
     scope :failed, -> { with_state('failed') }
     scope :valid, -> { where('state NOT IN (?)', %w(failed invalid)) }

From 2b8b6908921394beeb4f24647584f7cb5bd56e07 Mon Sep 17 00:00:00 2001
From: Matt-Yorkley <9029026+Matt-Yorkley@users.noreply.github.com>
Date: Fri, 9 Jul 2021 13:28:38 +0100
Subject: [PATCH 6/8] Tidy up :valid scope in Spree::Payment

---
 app/models/spree/payment.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/app/models/spree/payment.rb b/app/models/spree/payment.rb
index b41e085cde..f33e2eab87 100644
--- a/app/models/spree/payment.rb
+++ b/app/models/spree/payment.rb
@@ -49,7 +49,7 @@ module Spree
     scope :incomplete, -> { where(state: %w(checkout pending requires_authorization)) }
     scope :pending, -> { with_state('pending') }
     scope :failed, -> { with_state('failed') }
-    scope :valid, -> { where('state NOT IN (?)', %w(failed invalid)) }
+    scope :valid, -> { where.not(state: %w(failed invalid)) }
     scope :authorization_action_required, -> { where.not(cvv_response_message: nil) }
     scope :requires_authorization, -> { with_state("requires_authorization") }
     scope :with_payment_intent, ->(code) { where(response_code: code) }

From e6d9545c3064f7996a26f402078ac70d0ae8c454 Mon Sep 17 00:00:00 2001
From: Matt-Yorkley <9029026+Matt-Yorkley@users.noreply.github.com>
Date: Fri, 9 Jul 2021 13:29:49 +0100
Subject: [PATCH 7/8] Use :incomplete scope when voiding payments that can't be
 processed due to stock changes

---
 app/controllers/checkout_controller.rb       | 2 +-
 spec/controllers/checkout_controller_spec.rb | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/app/controllers/checkout_controller.rb b/app/controllers/checkout_controller.rb
index 37bdff3954..5d0487ed85 100644
--- a/app/controllers/checkout_controller.rb
+++ b/app/controllers/checkout_controller.rb
@@ -118,7 +118,7 @@ class CheckoutController < ::BaseController
   def cancel_incomplete_payments
     # The checkout could not complete due to stock running out. We void any pending (incomplete)
     # Stripe payments here as the order will need to be changed and resubmitted (or abandoned).
-    @order.payments.pending.each(&:void!)
+    @order.payments.incomplete.each(&:void!)
     flash[:notice] = I18n.t("checkout.payment_cancelled_due_to_stock")
   end
 
diff --git a/spec/controllers/checkout_controller_spec.rb b/spec/controllers/checkout_controller_spec.rb
index bde41ddce5..8e11b83bb5 100644
--- a/spec/controllers/checkout_controller_spec.rb
+++ b/spec/controllers/checkout_controller_spec.rb
@@ -118,7 +118,7 @@ describe CheckoutController, type: :controller do
           allow(controller).to receive(:valid_payment_intent_provided?) { true }
           order.save
           allow(order).to receive_message_chain(:payments, :completed) { [] }
-          allow(order).to receive_message_chain(:payments, :pending) { [payment] }
+          allow(order).to receive_message_chain(:payments, :incomplete) { [payment] }
         end
 
         it "cancels the payment and resets the order to cart" do

From 8e1631bfc7396a41f487ebca824600af6121155c Mon Sep 17 00:00:00 2001
From: Matt-Yorkley <9029026+Matt-Yorkley@users.noreply.github.com>
Date: Mon, 12 Jul 2021 08:14:14 +0100
Subject: [PATCH 8/8] Set adjustments associated with voided payments to
 ineligible.

Otherwise we can end up with duplicate transaction fees for voided payments.
---
 app/controllers/checkout_controller.rb       | 5 ++++-
 spec/controllers/checkout_controller_spec.rb | 7 +++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/app/controllers/checkout_controller.rb b/app/controllers/checkout_controller.rb
index 5d0487ed85..547f180a72 100644
--- a/app/controllers/checkout_controller.rb
+++ b/app/controllers/checkout_controller.rb
@@ -118,7 +118,10 @@ class CheckoutController < ::BaseController
   def cancel_incomplete_payments
     # The checkout could not complete due to stock running out. We void any pending (incomplete)
     # Stripe payments here as the order will need to be changed and resubmitted (or abandoned).
-    @order.payments.incomplete.each(&:void!)
+    @order.payments.incomplete.each do |payment|
+      payment.void!
+      payment.adjustment&.update_columns(eligible: false, state: "finalized")
+    end
     flash[:notice] = I18n.t("checkout.payment_cancelled_due_to_stock")
   end
 
diff --git a/spec/controllers/checkout_controller_spec.rb b/spec/controllers/checkout_controller_spec.rb
index 8e11b83bb5..e0e00a3ff7 100644
--- a/spec/controllers/checkout_controller_spec.rb
+++ b/spec/controllers/checkout_controller_spec.rb
@@ -110,6 +110,9 @@ describe CheckoutController, type: :controller do
       context "after redirecting back from Stripe" do
         let(:order) { create(:order_with_totals_and_distribution) }
         let!(:payment) { create(:payment, state: "pending", amount: order.total, order: order) }
+        let!(:transaction_fee) {
+          create(:adjustment, state: "open", amount: 10, order: order, adjustable: payment)
+        }
 
         before do
           allow(order).to receive_message_chain(:insufficient_stock_lines, :empty?).and_return(false)
@@ -119,6 +122,7 @@ describe CheckoutController, type: :controller do
           order.save
           allow(order).to receive_message_chain(:payments, :completed) { [] }
           allow(order).to receive_message_chain(:payments, :incomplete) { [payment] }
+          allow(payment).to receive(:adjustment) { transaction_fee }
         end
 
         it "cancels the payment and resets the order to cart" do
@@ -130,6 +134,9 @@ describe CheckoutController, type: :controller do
           expect(flash[:notice]).to eq I18n.t('checkout.payment_cancelled_due_to_stock')
 
           expect(order.state).to eq "cart"
+          expect(payment.state).to eq "void"
+          expect(transaction_fee.reload.eligible).to eq false
+          expect(transaction_fee.state).to eq "finalized"
         end
       end
     end