Ensure we are not comparing a string with a symbol in HasManyAssociation#inverse_updates_counter_cache?. Fixes #2755, where a counter cache could be decremented twice as far as it was supposed to be.

1 files changed, 10 insertions, 0 deletions

diff --git a/activerecord/test/cases/associations/has_many_associations_test.rb b/activerecord/test/cases/associations/has_many_associations_test.rb
index a2764f3e3b..1e59931963 100644
--- a/activerecord/test/cases/associations/has_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_many_associations_test.rb
@@ -17,6 +17,7 @@ require 'models/invoice'
 require 'models/line_item'
 require 'models/car'
 require 'models/bulb'
+require 'models/engine'
 
 class HasManyAssociationsTestForCountWithFinderSql < ActiveRecord::TestCase
   class Invoice < ActiveRecord::Base
@@ -850,6 +851,15 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     end
   end
 
+  def test_clearing_updates_counter_cache_when_inverse_counter_cache_is_a_symbol_with_dependent_destroy
+    car = Car.first
+    car.engines.create!
+
+    assert_difference 'car.reload.engines_count', -1 do
+      car.engines.clear
+    end
+  end
+
   def test_clearing_a_dependent_association_collection
     firm = companies(:first_firm)
     client_id = firm.dependent_clients_of_firm.first.id