Use #model_name on instances instead of classes

This allows rails code to be more confdent when asking for a model name, instead of having to ask for the class.

Rails core discussion here: https://groups.google.com/forum/#!topic/rubyonrails-core/ThSaXw9y1F8

4 files changed, 6 insertions, 6 deletions

diff --git a/actionview/lib/action_view/helpers/form_helper.rb b/actionview/lib/action_view/helpers/form_helper.rb
index 789a413c8d..bd8e3b1973 100644
--- a/actionview/lib/action_view/helpers/form_helper.rb
+++ b/actionview/lib/action_view/helpers/form_helper.rb
@@ -1815,8 +1815,8 @@ module ActionView
           object = convert_to_model(@object)
           key    = object ? (object.persisted? ? :update : :create) : :submit
 
-          model = if object.class.respond_to?(:model_name)
-            object.class.model_name.human
+          model = if object.respond_to?(:model_name)
+            object.model_name.human
           else
             @object_name.to_s.humanize
           end
diff --git a/actionview/lib/action_view/helpers/tags/label.rb b/actionview/lib/action_view/helpers/tags/label.rb
index a5bcaf8153..39b2f48c39 100644
--- a/actionview/lib/action_view/helpers/tags/label.rb
+++ b/actionview/lib/action_view/helpers/tags/label.rb
@@ -40,7 +40,7 @@ module ActionView
                         @object_name.gsub!(/\[(.*)_attributes\]\[\d+\]/, '.\1')
 
                         if object.respond_to?(:to_model)
-                          key = object.class.model_name.i18n_key
+                          key = object.model_name.i18n_key
                           i18n_default = ["#{key}.#{method_and_value}".to_sym, ""]
                         end
 
diff --git a/actionview/lib/action_view/model_naming.rb b/actionview/lib/action_view/model_naming.rb
index e09ebd60df..d42e436b17 100644
--- a/actionview/lib/action_view/model_naming.rb
+++ b/actionview/lib/action_view/model_naming.rb
@@ -6,7 +6,7 @@ module ActionView
     end
 
     def model_name_from_record_or_class(record_or_class)
-      (record_or_class.is_a?(Class) ? record_or_class : convert_to_model(record_or_class).class).model_name
+      convert_to_model(record_or_class).model_name
     end
   end
 end
diff --git a/actionview/test/activerecord/polymorphic_routes_test.rb b/actionview/test/activerecord/polymorphic_routes_test.rb
index fef27ef492..b03fe66e23 100644
--- a/actionview/test/activerecord/polymorphic_routes_test.rb
+++ b/actionview/test/activerecord/polymorphic_routes_test.rb
@@ -34,8 +34,8 @@ class ModelDelegator < ActiveRecord::Base
 end
 
 class ModelDelegate
-  def self.model_name
-    ActiveModel::Name.new(self)
+  def model_name
+    ActiveModel::Name.new(self.class)
   end
 
   def to_param