Fetch indexed variant overrides in one go

app/models/variant_override.rb

@@ -8,6 +8,12 @@ class VariantOverride < ActiveRecord::Base
     where(hub_id: hubs)
   }
 
+  def self.indexed(hub)
+    Hash[
+      for_hubs(hub).map { |vo| [vo.variant, vo] }
+    ]
+  end
+
   def self.price_for(hub, variant)
     self.for(hub, variant).andand.price
   end

lib/open_food_network/scope_product_to_hub.rb

@@ -4,17 +4,19 @@ module OpenFoodNetwork
   class ScopeProductToHub
     def initialize(hub)
       @hub = hub
+      @variant_overrides = VariantOverride.indexed @hub
     end
 
     def scope(product)
       product.send :extend, OpenFoodNetwork::ScopeProductToHub::ScopeProductToHub
       product.instance_variable_set :@hub, @hub
+      product.instance_variable_set :@variant_overrides, @variant_overrides
     end
 
 
     module ScopeProductToHub
       def variants_distributed_by(order_cycle, distributor)
-        super.each { |v| ScopeVariantToHub.new(@hub).scope(v) }
+        super.each { |v| ScopeVariantToHub.new(@hub, @variant_overrides).scope(v) }
       end
     end
   end

lib/open_food_network/scope_variant_to_hub.rb

@@ -1,13 +1,14 @@
 module OpenFoodNetwork
   class ScopeVariantToHub
-    def initialize(hub)
+    def initialize(hub, variant_overrides=nil)
       @hub = hub
+      @variant_overrides = variant_overrides || VariantOverride.indexed(@hub)
     end
 
     def scope(variant)
       variant.send :extend, OpenFoodNetwork::ScopeVariantToHub::ScopeVariantToHub
       variant.instance_variable_set :@hub, @hub
-      variant.instance_variable_set :@variant_override, VariantOverride.send(:for, @hub, variant)
+      variant.instance_variable_set :@variant_override, @variant_overrides[variant]
     end
 
 

spec/models/variant_override_spec.rb

@@ -14,8 +14,16 @@ describe VariantOverride do
     it "finds variant overrides for a set of hubs" do
       VariantOverride.for_hubs([hub1, hub2]).should match_array [vo1, vo2]
     end
+
+    describe "fetching variant overrides indexed by variant" do
+      it "gets indexed variant overrides for one hub" do
+        VariantOverride.indexed(hub1).should == {v => vo1}
+        VariantOverride.indexed(hub2).should == {v => vo2}
+      end
+    end
   end
 
+
   describe "looking up prices" do
     it "returns the numeric price when present" do
       VariantOverride.create!(variant: variant, hub: hub, price: 12.34)