Fix CollectionAssociation#replace to return new target (closes #6231)

2 files changed, 14 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/associations/collection_association.rb b/activerecord/lib/active_record/associations/collection_association.rb
index 00321ec860..56ec4c5c23 100644
--- a/activerecord/lib/active_record/associations/collection_association.rb
+++ b/activerecord/lib/active_record/associations/collection_association.rb
@@ -468,6 +468,8 @@ module ActiveRecord
             raise RecordNotSaved, "Failed to replace #{reflection.name} because one or more of the " \
                                   "new records could not be saved."
           end
+
+          new_target
         end
 
         def concat_records(records)
diff --git a/activerecord/test/cases/associations/has_many_associations_test.rb b/activerecord/test/cases/associations/has_many_associations_test.rb
index 13d8c68b33..2e24f8ebe1 100644
--- a/activerecord/test/cases/associations/has_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_many_associations_test.rb
@@ -1685,6 +1685,18 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     assert_equal [bulb2], car.reload.bulbs
   end
 
+  def test_replace_returns_new_target
+    car = Car.create(:name => 'honda')
+    bulb1 = car.bulbs.create
+    bulb2 = car.bulbs.create
+    bulb3 = Bulb.create
+
+    assert_equal [bulb1, bulb2], car.bulbs
+    result = car.bulbs.replace([bulb1, bulb3])
+    assert_equal [bulb1, bulb3], car.bulbs
+    assert_equal [bulb1, bulb3], result
+  end
+
   def test_building_has_many_association_with_restrict_dependency
     option_before = ActiveRecord::Base.dependent_restrict_raises
     ActiveRecord::Base.dependent_restrict_raises = true