1 files changed, 12 insertions, 0 deletions
diff --git a/activerecord/test/cases/dup_test.rb b/activerecord/test/cases/dup_test.rb
index 409d9a82e2..638cffe0e6 100644
--- a/activerecord/test/cases/dup_test.rb
+++ b/activerecord/test/cases/dup_test.rb
@@ -141,5 +141,17 @@ module ActiveRecord
     ensure
       Topic.default_scopes = prev_default_scopes
     end
+
+    def test_dup_without_primary_key
+      klass = Class.new(ActiveRecord::Base) do
+        self.table_name = 'parrots_pirates'
+      end
+
+      record = klass.create!
+
+      assert_nothing_raised do
+        record.dup
+      end
+    end
   end
 end