Fixed issue w/custom accessors + reserved name + inheritance

Fixed an issue where custom accessor methods (such as those generated by
`enum`) with the same name as a global method are incorrectly overridden
when subclassing.

This was partially fixed in 4155431 then broken again by e5f15a8.

Fixes #16288.

1 files changed, 18 insertions, 0 deletions

diff --git a/activerecord/test/cases/attribute_methods_test.rb b/activerecord/test/cases/attribute_methods_test.rb
index ab67cf4085..2c07b5cbad 100644
--- a/activerecord/test/cases/attribute_methods_test.rb
+++ b/activerecord/test/cases/attribute_methods_test.rb
@@ -810,6 +810,24 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_equal "lol", topic.author_name
   end
 
+  def test_inherited_custom_accessors_with_reserved_names
+    klass = Class.new(ActiveRecord::Base) do
+      self.table_name = 'computers'
+      self.abstract_class = true
+      def system; "omg"; end
+      def system=(val); self.developer = val; end
+    end
+
+    subklass = Class.new(klass)
+    [klass, subklass].each(&:define_attribute_methods)
+
+    computer = subklass.find(1)
+    assert_equal "omg", computer.system
+
+    computer.developer = 99
+    assert_equal 99, computer.developer
+  end
+
   def test_on_the_fly_super_invokable_generated_attribute_methods_via_method_missing
     klass = new_topic_like_ar_class do
       def title