rspec: card - optomize code: use shared example

venshop_app/spec/requests/card_pages_spec.rb

 require 'spec_helper'
 require 'set'
+shared_examples "calculate_price_list" do
+  it do
+    total = 0
+    Product.all.each do |product|
+      should have_xpath("//div[@id='cart-quantity-#{product.id}'][text()='#{amount}']")
+      should have_selector("#cart-unit-price-#{product.id}", text: ActionController::Base.helpers.number_with_delimiter(product.price))
+      should have_selector("#cart-total-price-#{product.id}", text: ActionController::Base.helpers.number_with_delimiter(product.price * amount))
+      total += product.price
+    end
+
+    should have_selector('#card-must-paid', text: ActionController::Base.helpers.number_with_delimiter(total))
+  end
+end
 
 def fill_in_order_form()
   fill_in "Full name", with: "Joseph Vu"
@@ -278,20 +291,12 @@ describe "CardPages" do
     end
 
     describe "calculate price" do
-      let(:amount) { 1 }
       before do
         visit url_for(controller: 'cards', action: 'checkout')
       end
-      it do
-        total = 0
-        Product.all.each do |product|
-          should have_xpath("//div[@id='cart-quantity-#{product.id}'][text()='#{amount}']")
-          should have_selector("#cart-unit-price-#{product.id}", text: ActionController::Base.helpers.number_with_delimiter(product.price))
-          should have_selector("#cart-total-price-#{product.id}", text: ActionController::Base.helpers.number_with_delimiter(product.price * amount))
-          total += product.price
-        end
 
-        should have_selector('#card-must-paid', text: ActionController::Base.helpers.number_with_delimiter(total))
+      it_behaves_like "calculate_price_list" do
+        let(:amount) { 1 }
       end
     end
   end
@@ -355,17 +360,8 @@ describe "CardPages" do
       end
 
       describe "calculate price" do
-        let(:amount) { 1 }
-        it do
-          total = 0
-          Product.all.each do |product|
-            should have_xpath("//div[@id='cart-quantity-#{product.id}'][text()='#{amount}']")
-            should have_selector("#cart-unit-price-#{product.id}", text: ActionController::Base.helpers.number_with_delimiter(product.price))
-            should have_selector("#cart-total-price-#{product.id}", text: ActionController::Base.helpers.number_with_delimiter(product.price * amount))
-            total += product.price
-          end
-
-          should have_selector('#card-must-paid', text: ActionController::Base.helpers.number_with_delimiter(total))
+        it_behaves_like "calculate_price_list" do
+          let(:amount) { 1 }
         end
       end
     end