Allow credit owed on payments made via stripe to be refunded via the admin section

app/assets/stylesheets/admin/icons.css.scss

@@ -1,3 +1,4 @@
 @import 'plugins/font-awesome';
 
 .icon-refund:before { @extend .icon-ok:before }
+.icon-credit:before { @extend .icon-ok:before }

app/models/spree/gateway/stripe_connect.rb

@@ -43,6 +43,11 @@ module Spree
         provider.void(response_code, gateway_options)
       end
 
+      def credit(money, _creditcard, response_code, gateway_options)
+        gateway_options[:stripe_account] = stripe_account_id
+        provider.refund(money, response_code, gateway_options)
+      end
+
       def create_profile(payment)
         return unless payment.source.gateway_customer_profile_id.nil?
 

spec/controllers/spree/admin/payments_controller_spec.rb

@@ -66,5 +66,59 @@ describe Spree::Admin::PaymentsController, type: :controller do
         end
       end
     end
+
+    context "requesting a partial credit on a payment" do
+      let(:params) { { id: payment.id, order_id: order.number, e: :credit } }
+
+      # Required for the respond override in the controller decorator to work
+      before { @request.env['HTTP_REFERER'] = spree.admin_order_payments_url(payment) }
+
+      context "that was processed by stripe" do
+        let!(:payment_method) { create(:stripe_payment_method, distributors: [shop], preferred_enterprise_id: shop.id) }
+        let!(:payment) { create(:payment, order: order, state: 'completed', payment_method: payment_method, response_code: 'ch_1a2b3c', amount: order.total + 5) }
+
+
+        before do
+          allow(Stripe).to receive(:api_key) { "sk_test_12345" }
+        end
+
+        context "where the request succeeds" do
+          before do
+            stub_request(:post, "https://sk_test_12345:@api.stripe.com/v1/charges/ch_1a2b3c/refunds").
+              to_return(:status => 200, :body => JSON.generate(id: 're_123', object: 'refund', status: 'succeeded') )
+          end
+
+          it "partially refunds the payment" do
+            order.reload
+            expect(order.payment_total).to eq order.total + 5
+            expect(order.outstanding_balance).to eq(-5)
+            spree_put :fire, params
+            expect(payment.reload.state).to eq 'completed'
+            order.reload
+            expect(order.payment_total).to eq order.total
+            expect(order.outstanding_balance).to eq 0
+          end
+        end
+
+        context "where the request fails" do
+          before do
+            stub_request(:post, "https://sk_test_12345:@api.stripe.com/v1/charges/ch_1a2b3c/refunds").
+              to_return(:status => 200, :body => JSON.generate(error: { message: "Bup-bow!"}) )
+          end
+
+          it "does not void the payment" do
+            order.reload
+            expect(order.payment_total).to eq order.total + 5
+            expect(order.outstanding_balance).to eq(-5)
+            spree_put :fire, params
+            expect(payment.reload.state).to eq 'completed'
+            order.reload
+            expect(order.payment_total).to eq order.total + 5
+            expect(order.outstanding_balance).to eq -5
+            expect(flash[:error]).to eq "Bup-bow!"
+          end
+        end
+      end
+    end
   end
 end