Merge pull request #8403 from senny/3313_after_find_is_triggered_too_often

Do not instantiate intermediate AR objects when eager loading.

2 files changed, 16 insertions, 0 deletions

diff --git a/activerecord/test/cases/associations/eager_test.rb b/activerecord/test/cases/associations/eager_test.rb
index 79612c8dee..94437380a4 100644
--- a/activerecord/test/cases/associations/eager_test.rb
+++ b/activerecord/test/cases/associations/eager_test.rb
@@ -944,6 +944,12 @@ class EagerAssociationTest < ActiveRecord::TestCase
     assert_equal 3, Developer.all.merge!(:includes => 'projects', :where => { 'developers_projects.access_level' => 1 }, :limit => 5).to_a.size
   end
 
+  def test_dont_create_temporary_active_record_instances
+    Developer.instance_count = 0
+    developers = Developer.all.merge!(:includes => 'projects', :where => { 'developers_projects.access_level' => 1 }, :limit => 5).to_a
+    assert_equal developers.count, Developer.instance_count
+  end
+
   def test_order_on_join_table_with_include_and_limit
     assert_equal 5, Developer.all.merge!(:includes => 'projects', :order => 'developers_projects.joined_on DESC', :limit => 5).to_a.size
   end
diff --git a/activerecord/test/models/developer.rb b/activerecord/test/models/developer.rb
index 622dd75aeb..1c048bb6b4 100644
--- a/activerecord/test/models/developer.rb
+++ b/activerecord/test/models/developer.rb
@@ -57,6 +57,16 @@ class Developer < ActiveRecord::Base
   def log=(message)
     audit_logs.build :message => message
   end
+
+  after_find :track_instance_count
+  cattr_accessor :instance_count
+
+  def track_instance_count
+    self.class.instance_count ||= 0
+    self.class.instance_count += 1
+  end
+  private :track_instance_count
+
 end
 
 class AuditLog < ActiveRecord::Base