Calling to_proc is faster than argumentless method

core/app/models/spree/order_updater.rb

@@ -136,16 +136,12 @@ def update_totals
     end
 
     def update_shipment_amounts
-      shipments.each do |shipment|
-        shipment.update_amounts
-      end
+      shipments.each(&:update_amounts)
     end
 
     # give each of the shipments a chance to update themselves
     def update_shipments
-      shipments.each do |shipment|
-        shipment.update_state
-      end
+      shipments.each(&:update_state)
     end
 
     def update_payment_total

core/lib/spree/testing_support/factories/reimbursement_factory.rb

@@ -15,7 +15,7 @@
       if reimbursement.return_items.empty?
         reimbursement.return_items = reimbursement.customer_return.return_items
       end
-      reimbursement.total = reimbursement.return_items.map { |ri| ri.amount }.sum
+      reimbursement.total = reimbursement.return_items.sum(&:amount)
     end
   end
 end

core/lib/spree/testing_support/shared_examples/gallery.rb

@@ -10,7 +10,7 @@
       include_context 'has multiple images'
 
       it 'has the associated images' do
-        expect(subject.map { |picture| picture.id }).
+        expect(subject.map(&:id)).
           to match_array([first_image.id, second_image.id])
       end
     end

core/spec/models/spree/stock/simple_coordinator_spec.rb

@@ -119,7 +119,7 @@ module Stock
         shared_examples "a fulfillable package" do
           it "packages correctly" do
             expect(shipments).not_to be_empty
-            inventory_units = shipments.flat_map { |shipment| shipment.inventory_units }
+            inventory_units = shipments.flat_map(&:inventory_units)
             expect(inventory_units.size).to eq(5)
             expect(inventory_units.uniq.size).to eq(5)
           end

core/spec/models/spree/taxon_spec.rb

@@ -190,7 +190,7 @@
       it 'returns all descendant variants' do
         variants = taxon.all_variants
         expect(variants.count).to eq(9)
-        expect(variants).to match_array([product1, product2, product3].flat_map{ |p| p.variants_including_master })
+        expect(variants).to match_array([product1, product2, product3].flat_map(&:variants_including_master))
       end
     end
   end