Add spec to cover SQL query issue with OCs where the only products from the coordinator inventory are renderer

spec/services/exchange_products_renderer_spec.rb

@@ -7,8 +7,9 @@ describe ExchangeProductsRenderer do
 
   describe "#exchange_products" do
     describe "for an incoming exchange" do
+      let(:exchange) { order_cycle.exchanges.incoming.first }
+
       it "loads products" do
-        exchange = order_cycle.exchanges.incoming.first
         products = renderer.exchange_products(true, exchange.sender)
 
         expect(products.first.supplier.name).to eq exchange.variants.first.product.supplier.name
@@ -16,14 +17,34 @@ describe ExchangeProductsRenderer do
     end
 
     describe "for an outgoing exchange" do
+      let(:exchange) { order_cycle.exchanges.outgoing.first }
+
       it "loads products" do
-        exchange = order_cycle.exchanges.outgoing.first
         products = renderer.exchange_products(false, exchange.receiver)
 
         suppliers = [exchange.variants[0].product.supplier.name, exchange.variants[1].product.supplier.name]
         expect(suppliers).to include products.first.supplier.name
         expect(suppliers).to include products.second.supplier.name
       end
+
+      context "showing products from coordinator inventory only" do
+        before { order_cycle.update prefers_product_selection_from_coordinator_inventory_only: true }
+
+        it "loads no products if there are no products from the coordinator inventory" do
+          products = renderer.exchange_products(false, exchange.receiver)
+
+          expect(products).to be_empty
+        end
+
+        it "loads products from the coordinator inventory" do
+          # Add variant already in the exchange to the coordinator's inventory
+          exchange.variants.first.inventory_items = [create(:inventory_item, enterprise: order_cycle.coordinator)]
+
+          products = renderer.exchange_products(false, exchange.receiver)
+
+          expect(products).to eq [exchange.variants.first.product]
+        end
+      end
     end
   end