query the association rather than send the method for the association name

2 files changed, 10 insertions, 11 deletions

diff --git a/activerecord/lib/active_record/associations/preloader/through_association.rb b/activerecord/lib/active_record/associations/preloader/through_association.rb
index de06931845..b2e8f32625 100644
--- a/activerecord/lib/active_record/associations/preloader/through_association.rb
+++ b/activerecord/lib/active_record/associations/preloader/through_association.rb
@@ -27,17 +27,18 @@ module ActiveRecord
         def through_records_by_owner
           Preloader.new(owners, through_reflection.name, through_scope).run
 
-          Hash[owners.map do |owner|
-            through_records = Array.wrap(owner.send(through_reflection.name))
+          owners.each_with_object({}) do |owner, h|
+            association = owner.association through_reflection.name
+            through_records = Array(association.reader)
 
             # Dont cache the association - we would only be caching a subset
             if (through_scope != through_reflection.klass.unscoped) ||
                (reflection.options[:source_type] && through_reflection.collection?)
-              owner.association(through_reflection.name).reset
+              association.reset
             end
 
-            [owner, through_records]
-          end]
+            h[owner] = through_records
+          end
         end
 
         def through_scope
diff --git a/activerecord/test/cases/associations/cascaded_eager_loading_test.rb b/activerecord/test/cases/associations/cascaded_eager_loading_test.rb
index e693d34f99..811d91f849 100644
--- a/activerecord/test/cases/associations/cascaded_eager_loading_test.rb
+++ b/activerecord/test/cases/associations/cascaded_eager_loading_test.rb
@@ -52,12 +52,10 @@ class CascadedEagerLoadingTest < ActiveRecord::TestCase
   def test_cascaded_eager_association_loading_with_join_for_count
     categories = Category.joins(:categorizations).includes([{:posts=>:comments}, :authors])
 
-    assert_nothing_raised do
-      assert_equal 4, categories.count
-      assert_equal 4, categories.to_a.count
-      assert_equal 3, categories.distinct.count
-      assert_equal 3, categories.to_a.uniq.size # Must uniq since instantiating with inner joins will get dupes
-    end
+    assert_equal 4, categories.count
+    assert_equal 4, categories.to_a.count
+    assert_equal 3, categories.distinct.count
+    assert_equal 3, categories.to_a.uniq.size # Must uniq since instantiating with inner joins will get dupes
   end
 
   def test_cascaded_eager_association_loading_with_duplicated_includes