Give preference to to_a over arel from Relation#method_missing

activerecord/lib/active_record/locking/optimistic.rb

@@ -81,8 +81,8 @@ module ActiveRecord
             relation = self.class.unscoped
 
             affected_rows = relation.where(
-              relation[self.class.primary_key].eq(quoted_id).and(
-                relation[self.class.locking_column].eq(quote_value(previous_value))
+              relation.table[self.class.primary_key].eq(quoted_id).and(
+                relation.table[self.class.locking_column].eq(quote_value(previous_value))
               )
             ).update(arel_attributes_values(false, false, attribute_names))
 

activerecord/lib/active_record/relation.rb

@@ -8,6 +8,7 @@ module ActiveRecord
     include FinderMethods, Calculations, SpawnMethods, QueryMethods
 
     delegate :length, :collect, :map, :each, :all?, :include?, :to => :to_a
+    delegate :insert, :update, :where_clause, :to => :arel
 
     attr_reader :table, :klass
 
@@ -139,10 +140,10 @@ module ActiveRecord
     protected
 
     def method_missing(method, *args, &block)
-      if arel.respond_to?(method)
-        arel.send(method, *args, &block)
-      elsif Array.method_defined?(method)
+      if Array.method_defined?(method)
         to_a.send(method, *args, &block)
+      elsif arel.respond_to?(method)
+        arel.send(method, *args, &block)
       elsif match = DynamicFinderMatch.match(method)
         attributes = match.attribute_names
         super unless @klass.send(:all_attributes_exists?, attributes)

activerecord/test/cases/named_scope_test.rb

@@ -379,6 +379,12 @@ class NamedScopeTest < ActiveRecord::TestCase
   def test_deprecated_named_scope_method
     assert_deprecated('named_scope has been deprecated') { Topic.named_scope :deprecated_named_scope }
   end
+
+  def test_index_on_named_scope
+    approved = Topic.approved.order('id ASC')
+    assert_equal topics(:second), approved[0]
+    assert approved.loaded?
+  end
 end
 
 class DynamicScopeMatchTest < ActiveRecord::TestCase