Merge pull request #40540 from sekiyama58/has_many_find_multi_id_inve…

…rse_of

Set the inverse record on find with multiple ids from has_many association

activerecord/lib/active_record/relation/spawn_methods.rb

@@ -69,8 +69,8 @@ def only(*onlies)
 
     private
       def relation_with(values)
-        result = Relation.create(klass, values: values)
-        result.extend(*extending_values) if extending_values.any?
+        result = spawn
+        result.instance_variable_set(:@values, values)
         result
       end
   end

activerecord/test/cases/associations/inverse_associations_test.rb

@@ -509,6 +509,24 @@ def test_find_on_child_instance_with_id_should_not_load_all_child_records
     assert_not_predicate human.interests, :loaded?
   end
 
+  def test_find_on_child_instance_with_id_should_set_inverse_instances
+    human = Human.create!
+    interest = Interest.create!(human: human)
+
+    child = human.interests.find(interest.id)
+    assert_predicate child.association(:human), :loaded?
+  end
+
+  def test_find_on_child_instances_with_ids_should_set_inverse_instances
+    human = Human.create!
+    interests = Array.new(2) { Interest.create!(human: human) }
+
+    children = human.interests.find(interests.pluck(:id))
+    children.each do |child|
+      assert_predicate child.association(:human), :loaded?
+    end
+  end
+
   def test_raise_record_not_found_error_when_invalid_ids_are_passed
     # delete all interest records to ensure that hard coded invalid_id(s)
     # are indeed invalid.