Merge pull request #36708 from rails/has-one-polymorphic-touch-dont-cache-association-result-inside-create-transaction

Polymorphic has_one touch: Don't cache association result inside crea…

activerecord/lib/active_record/associations/association.rb

@@ -56,6 +56,10 @@ def reset
         @inversed = false
       end
 
+      def reset_negative_cache # :nodoc:
+        reset if loaded? && target.nil?
+      end
+
       # Reloads the \target and returns +self+ on success.
       # The QueryCache is cleared if +force+ is true.
       def reload(force = false)

activerecord/lib/active_record/associations/builder/has_one.rb

@@ -32,15 +32,12 @@ def self.define_validations(model, reflection)
       end
     end
 
-    def self.touch_record(o, name, touch)
-      record = o.send name
+    def self.touch_record(record, name, touch)
+      instance = record.send(name)
 
-      return unless record && record.persisted?
-
-      if touch != true
-        record.touch(touch)
-      else
-        record.touch
+      if instance&.persisted?
+        touch != true ?
+          instance.touch(touch) : instance.touch
       end
     end
 
@@ -48,11 +45,9 @@ def self.add_touch_callbacks(model, reflection)
       name  = reflection.name
       touch = reflection.options[:touch]
 
-      callback = lambda { |record|
-        HasOne.touch_record(record, name, touch)
-      }
-
+      callback = -> (record) { HasOne.touch_record(record, name, touch) }
       model.after_create callback, if: :saved_changes?
+      model.after_create_commit { association(name).reset_negative_cache }
       model.after_update callback, if: :saved_changes?
       model.after_destroy callback
       model.after_touch callback

activerecord/test/cases/associations/has_one_associations_test.rb

@@ -709,6 +709,24 @@ def test_has_one_with_touch_option_on_create
     }
   end
 
+  def test_polymorphic_has_one_with_touch_option_on_create_wont_cache_association_so_fetching_after_transaction_commit_works
+    assert_queries(4) {
+      chef = Chef.create(employable: DrinkDesignerWithPolymorphicTouchChef.new)
+      employable = chef.employable
+
+      assert_equal chef, employable.chef
+    }
+  end
+
+  def test_polymorphic_has_one_with_touch_option_on_update_will_touch_record_by_fetching_from_database_if_needed
+    DrinkDesignerWithPolymorphicTouchChef.create(chef: Chef.new)
+    designer = DrinkDesignerWithPolymorphicTouchChef.last
+
+    assert_queries(3) {
+      designer.update(name: "foo")
+    }
+  end
+
   def test_has_one_with_touch_option_on_update
     new_club = Club.create(name: "1000 Oaks")
     new_club.create_membership

activerecord/test/models/drink_designer.rb

@@ -10,5 +10,11 @@ class DrinkDesignerWithPolymorphicDependentNullifyChef < ActiveRecord::Base
   has_one :chef, as: :employable, dependent: :nullify
 end
 
+class DrinkDesignerWithPolymorphicTouchChef < ActiveRecord::Base
+  self.table_name = "drink_designers"
+
+  has_one :chef, as: :employable, touch: true
+end
+
 class MocktailDesigner < DrinkDesigner
 end

activerecord/test/schema/schema.rb

@@ -1070,6 +1070,7 @@
   create_table :cake_designers, force: true do |t|
   end
   create_table :drink_designers, force: true do |t|
+    t.string :name
   end
   create_table :chefs, force: true do |t|
     t.integer :employable_id
@@ -1077,6 +1078,7 @@
     t.integer :department_id
     t.string :employable_list_type
     t.integer :employable_list_id
+    t.timestamps
   end
   create_table :recipes, force: true do |t|
     t.integer :chef_id