Merge pull request #35247 from bogdan/fix-source-reflection-reset-code

Fix reset of the source association when through association is loaded

2 files changed, 10 insertions, 21 deletions

diff --git a/activerecord/lib/active_record/associations/preloader/association.rb b/activerecord/lib/active_record/associations/preloader/association.rb
index 041e62077c..7048ff43b8 100644
--- a/activerecord/lib/active_record/associations/preloader/association.rb
+++ b/activerecord/lib/active_record/associations/preloader/association.rb
@@ -115,7 +115,7 @@ module ActiveRecord
           def build_scope
             scope = klass.scope_for_association
 
-            if reflection.type
+            if reflection.type && !reflection.through_reflection?
               scope.where!(reflection.type => model.polymorphic_name)
             end
 
diff --git a/activerecord/lib/active_record/associations/preloader/through_association.rb b/activerecord/lib/active_record/associations/preloader/through_association.rb
index a6b7ab80a2..25254e652a 100644
--- a/activerecord/lib/active_record/associations/preloader/through_association.rb
+++ b/activerecord/lib/active_record/associations/preloader/through_association.rb
@@ -7,10 +7,9 @@ module ActiveRecord
         def run(preloader)
           already_loaded     = owners.first.association(through_reflection.name).loaded?
           through_scope      = through_scope()
-          reflection_scope   = target_reflection_scope
           through_preloaders = preloader.preload(owners, through_reflection.name, through_scope)
           middle_records     = through_preloaders.flat_map(&:preloaded_records)
-          preloaders         = preloader.preload(middle_records, source_reflection.name, reflection_scope)
+          preloaders         = preloader.preload(middle_records, source_reflection.name, scope)
           @preloaded_records = preloaders.flat_map(&:preloaded_records)
 
           owners.each do |owner|
@@ -25,18 +24,18 @@ module ActiveRecord
               owner.association(through_reflection.name).reset if through_scope
             end
             result = through_records.flat_map do |record|
-              association = record.association(source_reflection.name)
-              target = association.target
-              association.reset if preload_scope
-              target
+              record.association(source_reflection.name).target
             end
             result.compact!
-            if reflection_scope
-              result.sort_by! { |rhs| preload_index[rhs] } if reflection_scope.order_values.any?
-              result.uniq! if reflection_scope.distinct_value
-            end
+            result.sort_by! { |rhs| preload_index[rhs] } if scope.order_values.any?
+            result.uniq! if scope.distinct_value
             associate_records_to_owner(owner, result)
           end
+          unless scope.empty_scope?
+            middle_records.each do |owner|
+              owner.association(source_reflection.name).reset
+            end
+          end
         end
 
         private
@@ -91,16 +90,6 @@ module ActiveRecord
 
             scope unless scope.empty_scope?
           end
-
-          def target_reflection_scope
-            if preload_scope
-              reflection_scope.merge(preload_scope)
-            elsif reflection.scope
-              reflection_scope
-            else
-              nil
-            end
-          end
       end
     end
   end