Revert change on ActiveRecord::Relation#order method that prepends new

order on the old ones

The previous behavior added a major backward incompatibility since it
impossible to have a upgrade path without major changes on the
application code.

We are taking the most conservative path to be consistent with the idea
of having a smoother upgrade on Rails 4.

We are reverting the behavior for what was in Rails 3.x and,
if needed, we will implement a new API to prepend the order clauses in
Rails 4.1.

Conflicts:
	activerecord/CHANGELOG.md
	activerecord/lib/active_record/relation/query_methods.rb
	guides/source/upgrading_ruby_on_rails.md

Author: rafaelfranca

activerecord/CHANGELOG.md

@@ -1,5 +1,20 @@
 ## unreleased ##
 
+*   Revert `ActiveRecord::Relation#order` change that make new order
+    prepend the old one.
+
+    Before:
+
+        User.order("name asc").order("created_at desc")
+        # SELECT * FROM users ORDER BY created_at desc, name asc
+
+    After:
+
+        User.order("name asc").order("created_at desc")
+        # SELECT * FROM users ORDER BY name asc, created_at desc
+
+    This also affects order defined in `default_scope` or any kind of associations.
+
 *   When using optimistic locking, `update` was not passing the column to `quote_value`
     to allow the connection adapter to properly determine how to quote the value. This was
     affecting certain databases that use specific colmn types.

activerecord/lib/active_record/relation/query_methods.rb

@@ -289,7 +289,7 @@ def order!(*args) # :nodoc:
         arg.is_a?(Symbol) ? "#{quoted_table_name}.#{arg} ASC" : arg
       }
 
-      self.order_values = args + self.order_values
+      self.order_values += args
       self
     end
 
@@ -301,7 +301,7 @@ def order!(*args) # :nodoc:
     #
     #   User.order('email DESC').reorder('id ASC').order('name ASC')
     #
-    # generates a query with 'ORDER BY name ASC, id ASC'.
+    # generates a query with 'ORDER BY id ASC, name ASC'.
     def reorder(*args)
       check_if_method_has_arguments!("reorder", args)
       spawn.reorder!(*args)

activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb

@@ -570,9 +570,9 @@ def test_dynamic_find_should_respect_association_order
     assert_equal high_id_jamis, projects(:active_record).developers.find_by_name('Jamis')
   end
 
-  def test_find_should_prepend_to_association_order
+  def test_find_should_append_to_association_order
     ordered_developers = projects(:active_record).developers.order('projects.id')
-    assert_equal ['projects.id', 'developers.name desc, developers.id desc'], ordered_developers.order_values
+    assert_equal ['developers.name desc, developers.id desc', 'projects.id'], ordered_developers.order_values
   end
 
   def test_dynamic_find_all_should_respect_readonly_access

activerecord/test/cases/associations/has_many_associations_test.rb

@@ -308,9 +308,9 @@ def test_find_many_with_merged_options
     assert_equal 2, companies(:first_firm).limited_clients.limit(nil).to_a.size
   end
 
-  def test_find_should_prepend_to_association_order
+  def test_find_should_append_to_association_order
     ordered_clients =  companies(:first_firm).clients_sorted_desc.order('companies.id')
-    assert_equal ['companies.id', 'id DESC'], ordered_clients.order_values
+    assert_equal ['id DESC', 'companies.id'], ordered_clients.order_values
   end
 
   def test_dynamic_find_should_respect_association_order

activerecord/test/cases/relations_test.rb

@@ -180,7 +180,7 @@ def test_finding_last_with_arel_order
   end
 
   def test_finding_with_order_concatenated
-    topics = Topic.order('title').order('author_name')
+    topics = Topic.order('author_name').order('title')
     assert_equal 4, topics.to_a.size
     assert_equal topics(:fourth).title, topics.first.title
   end
@@ -1174,20 +1174,20 @@ def test_order_by_relation_attribute
   end
 
   def test_default_scope_order_with_scope_order
-    assert_equal 'honda', CoolCar.order_using_new_style.limit(1).first.name
-    assert_equal 'honda', FastCar.order_using_new_style.limit(1).first.name
+    assert_equal 'zyke', CoolCar.order_using_new_style.limit(1).first.name
+    assert_equal 'zyke', FastCar.order_using_new_style.limit(1).first.name
   end
 
   def test_order_using_scoping
     car1 = CoolCar.order('id DESC').scoping do
-      CoolCar.all.merge!(:order => 'id asc').first
+      CoolCar.all.merge!(order: 'id asc').first
     end
-    assert_equal 'honda', car1.name
+    assert_equal 'zyke', car1.name
 
     car2 = FastCar.order('id DESC').scoping do
-      FastCar.all.merge!(:order => 'id asc').first
+      FastCar.all.merge!(order: 'id asc').first
     end
-    assert_equal 'honda', car2.name
+    assert_equal 'zyke', car2.name
   end
 
   def test_unscoped_block_style

activerecord/test/cases/scoping/default_scoping_test.rb

@@ -79,7 +79,7 @@ def test_default_scope_with_multiple_calls
   end
 
   def test_scope_overwrites_default
-    expected = Developer.all.merge!(:order => ' name DESC, salary DESC').to_a.collect { |dev| dev.name }
+    expected = Developer.all.merge!(order: 'salary DESC, name DESC').to_a.collect { |dev| dev.name }
     received = DeveloperOrderedBySalary.by_name.to_a.collect { |dev| dev.name }
     assert_equal expected, received
   end
@@ -91,7 +91,7 @@ def test_reorder_overrides_default_scope_order
   end
 
   def test_order_after_reorder_combines_orders
-    expected = Developer.order('id DESC, name DESC').collect { |dev| [dev.name, dev.id] }
+    expected = Developer.order('name DESC, id DESC').collect { |dev| [dev.name, dev.id] }
     received = Developer.order('name ASC').reorder('name DESC').order('id DESC').collect { |dev| [dev.name, dev.id] }
     assert_equal expected, received
   end
@@ -251,8 +251,8 @@ def test_unscope_errors_with_non_symbol_or_hash_arguments
   end
 
   def test_order_in_default_scope_should_not_prevail
-    expected = Developer.all.merge!(:order => 'salary').to_a.collect { |dev| dev.salary }
-    received = DeveloperOrderedBySalary.all.merge!(:order => 'salary').to_a.collect { |dev| dev.salary }
+    expected = Developer.all.merge!(order: 'salary desc').to_a.collect { |dev| dev.salary }
+    received = DeveloperOrderedBySalary.all.merge!(order: 'salary').to_a.collect { |dev| dev.salary }
     assert_equal expected, received
   end
 

guides/source/active_record_querying.md

@@ -543,11 +543,11 @@ Client.order("orders_count ASC, created_at DESC")
 Client.order("orders_count ASC", "created_at DESC")
 ```
 
-If you want to call `order` multiple times e.g. in different context, new order will prepend previous one
+If you want to call `order` multiple times e.g. in different context, new order will append previous one
 
 ```ruby
 Client.order("orders_count ASC").order("created_at DESC")
-# SELECT * FROM clients ORDER BY created_at DESC, orders_count ASC
+# SELECT * FROM clients ORDER BY orders_count ASC, created_at DESC
 ```
 
 Selecting Specific Fields

guides/source/upgrading_ruby_on_rails.md

@@ -53,7 +53,7 @@ Rails 4.0 no longer supports loading plugins from `vendor/plugins`. You must rep
 
 * The `delete` method in collection associations can now receive `Fixnum` or `String` arguments as record ids, besides records, pretty much like the `destroy` method does. Previously it raised `ActiveRecord::AssociationTypeMismatch` for such arguments. From Rails 4.0 on `delete` automatically tries to find the records matching the given ids before deleting them.
 
-* Rails 4.0 has changed how orders get stacked in `ActiveRecord::Relation`. In previous versions of Rails, the new order was applied after the previously defined order. But this is no longer true. Check [Active Record Query guide](active_record_querying.html#ordering) for more information.
+* In Rails 4.0 when a column or a table is renamed the related indexes are also renamed. If you have migrations which rename the indexes, they are no longer needed.
 
 * Rails 4.0 has changed `serialized_attributes` and `attr_readonly` to class methods only. You shouldn't use instance methods since it's now deprecated. You should change them to use class methods, e.g. `self.serialized_attributes` to `self.class.serialized_attributes`.