1 files changed, 7 insertions, 0 deletions
diff --git a/activerecord/test/cases/attribute_methods_test.rb b/activerecord/test/cases/attribute_methods_test.rb
index fb53eb1a4b..cdff7ef017 100644
--- a/activerecord/test/cases/attribute_methods_test.rb
+++ b/activerecord/test/cases/attribute_methods_test.rb
@@ -780,6 +780,13 @@ class AttributeMethodsTest < ActiveRecord::TestCase
     assert_deprecated { klass.define_attribute_methods }
   end
 
+  def test_setting_new_attributes_deprecated
+    t = Topic.new
+    assert_deprecated { t[:foo] = "bar" }
+    assert_equal "bar", t.foo
+    assert_equal "bar", t[:foo]
+  end
+
   private
   def cached_columns
     @cached_columns ||= time_related_columns_on_topic.map(&:name)