Restore behavior of Active Record 3.2.3 scopes

A series of commits relating to preloading and scopes caused a regression.
Cloning the relation calls initialize_copy which resets a number of instance
variables to nil. Without this the scope thinks that it is already loaded
when it is called again.

Reverts the following commits:
13f1401a6cf0266a3b0a91b173f976db2d4e50f3
8491740ca5361ba9df20e1c8b906c709f5bfbc12
dffbb521a0d00c8673a3ad6e0e8ff526f32daf4e

Fixes #6575, #6576 & #6577

4 files changed, 4 insertions, 31 deletions

diff --git a/activerecord/lib/active_record/associations/preloader/association.rb b/activerecord/lib/active_record/associations/preloader/association.rb
index ab50e43ea0..779f8164cc 100644
--- a/activerecord/lib/active_record/associations/preloader/association.rb
+++ b/activerecord/lib/active_record/associations/preloader/association.rb
@@ -77,7 +77,7 @@ module ActiveRecord
             # Some databases impose a limit on the number of ids in a list (in Oracle it's 1000)
             # Make several smaller queries if necessary or make one query if the adapter supports it
             sliced  = owner_keys.each_slice(model.connection.in_clause_length || owner_keys.size)
-            records = sliced.map { |slice| records_for(slice).to_a }.flatten
+            records = sliced.map { |slice| records_for(slice) }.flatten
           end
 
           # Each record may have multiple owners, and vice-versa
@@ -93,8 +93,7 @@ module ActiveRecord
         end
 
         def build_scope
-          scope = klass.unscoped
-          scope.default_scoped = true
+          scope = klass.scoped
 
           scope = scope.where(process_conditions(options[:conditions]))
           scope = scope.where(process_conditions(preload_options[:conditions]))
diff --git a/activerecord/lib/active_record/scoping/named.rb b/activerecord/lib/active_record/scoping/named.rb
index d6b0265fb3..9c50baa647 100644
--- a/activerecord/lib/active_record/scoping/named.rb
+++ b/activerecord/lib/active_record/scoping/named.rb
@@ -34,7 +34,7 @@ module ActiveRecord
             if current_scope
               current_scope.clone
             else
-              scope = relation
+              scope = relation.clone
               scope.default_scoped = true
               scope
             end
@@ -48,7 +48,7 @@ module ActiveRecord
           if current_scope
             current_scope.scope_for_create
           else
-            scope = relation
+            scope = relation.clone
             scope.default_scoped = true
             scope.scope_for_create
           end
diff --git a/activerecord/test/cases/associations/eager_test.rb b/activerecord/test/cases/associations/eager_test.rb
index d7af07f9c7..1dc71ac4cc 100644
--- a/activerecord/test/cases/associations/eager_test.rb
+++ b/activerecord/test/cases/associations/eager_test.rb
@@ -1095,28 +1095,4 @@ class EagerAssociationTest < ActiveRecord::TestCase
       Post.includes(:comments).order(nil).where(:comments => {:body => "Thank you for the welcome"}).first
     end
   end
-
-  def test_deep_including_through_habtm
-    posts = Post.find(:all, :include => {:categories => :categorizations}, :order => "posts.id, categories.id")
-    assert_no_queries { assert_equal 2, posts[0].categories[0].categorizations.length }
-    assert_no_queries { assert_equal 1, posts[0].categories[1].categorizations.length }
-    assert_no_queries { assert_equal 2, posts[1].categories[0].categorizations.length }
-  end
-
-  test "scoping with a circular preload" do
-    assert_equal Comment.find(1), Comment.preload(:post => :comments).scoping { Comment.find(1) }
-  end
-
-  test "circular preload does not modify unscoped" do
-    expected = FirstPost.unscoped.find(2)
-    FirstPost.preload(:comments => :first_post).find(1)
-    assert_equal expected, FirstPost.unscoped.find(2)
-  end
-
-  test "preload ignores the scoping" do
-    assert_equal(
-      Comment.find(1).post,
-      Post.where('1 = 0').scoping { Comment.preload(:post).find(1).post }
-    )
-  end
 end
diff --git a/activerecord/test/models/comment.rb b/activerecord/test/models/comment.rb
index bca937a299..88b139d931 100644
--- a/activerecord/test/models/comment.rb
+++ b/activerecord/test/models/comment.rb
@@ -11,8 +11,6 @@ class Comment < ActiveRecord::Base
   belongs_to :post, :counter_cache => true
   has_many :ratings
 
-  belongs_to :first_post, :foreign_key => :post_id
-
   has_many :children, :class_name => 'Comment', :foreign_key => :parent_id
   belongs_to :parent, :class_name => 'Comment', :counter_cache => :children_count