Simplify cases where pagination is conditional and pagination data may or may not be used

app/controllers/admin/bulk_line_items_controller.rb

@@ -15,12 +15,11 @@ module Admin
         ransack(params[:q]).result.
         reorder('spree_line_items.order_id ASC, spree_line_items.id ASC')
 
-      pagy = nil
-      pagy, @line_items = pagy(@line_items) if pagination_required?
+      @pagy, @line_items = pagy(@line_items) if pagination_required?
 
       render json: {
         line_items: serialized_line_items,
-        pagination: pagination_data(pagy)
+        pagination: pagination_data
       }
     end
 

app/controllers/api/v0/exchange_products_controller.rb

@@ -73,8 +73,9 @@ module Api
       end
 
       def render_paginated_products
-        pagy, results = nil, products
-        pagy, results = pagy(results, items: params[:per_page] || DEFAULT_PER_PAGE) if pagination_required?
+        results = products
+
+        @pagy, results = pagy(results, items: params[:per_page] || DEFAULT_PER_PAGE) if pagination_required?
 
         serialized_products = ActiveModel::ArraySerializer.new(
           results,
@@ -84,7 +85,7 @@ module Api
 
         render json: {
           products: serialized_products,
-          pagination: pagination_data(pagy)
+          pagination: pagination_data
         }
       end
 

app/controllers/api/v0/orders_controller.rb

@@ -15,11 +15,11 @@ module Api
 
         orders = SearchOrders.new(params, current_api_user).orders
 
-        pagy, paged_orders = pagy(orders, items: params[:per_page] || default_per_page)
+        @pagy, paged_orders = pagy(orders, items: params[:per_page] || default_per_page)
 
         render json: {
           orders: serialized_orders(paged_orders),
-          pagination: pagination_data(pagy)
+          pagination: pagination_data
         }
       end
 

app/controllers/api/v0/products_controller.rb

@@ -132,7 +132,7 @@ module Api
       end
 
       def render_paged_products(products, product_serializer = ::Api::Admin::ProductSerializer)
-        pagy, products = pagy(products, items: params[:per_page] || DEFAULT_PER_PAGE)
+        @pagy, products = pagy(products, items: params[:per_page] || DEFAULT_PER_PAGE)
 
         serialized_products = ActiveModel::ArraySerializer.new(
           products,
@@ -141,7 +141,7 @@ module Api
 
         render json: {
           products: serialized_products,
-          pagination: pagination_data(pagy)
+          pagination: pagination_data
         }
       end
 

app/controllers/concerns/pagination_data.rb

@@ -3,12 +3,12 @@
 module PaginationData
   extend ActiveSupport::Concern
 
-  def pagination_data(pagination)
-    return unless pagination.respond_to? :pages
+  def pagination_data
+    return unless defined? @pagy
 
     {
-      results: pagination.count,
-      pages: pagination.pages,
+      results: @pagy.count,
+      pages: @pagy.pages,
       page: (params[:page] || 1).to_i,
       per_page: (params[:per_page] || default_per_page).to_i
     }