1 files changed, 7 insertions, 0 deletions
diff --git a/activerecord/test/cases/attribute_test.rb b/activerecord/test/cases/attribute_test.rb
index a24a4fc6a4..b1b8639696 100644
--- a/activerecord/test/cases/attribute_test.rb
+++ b/activerecord/test/cases/attribute_test.rb
@@ -242,5 +242,12 @@ module ActiveRecord
         attribute.with_value_from_user(1)
       end
     end
+
+    test "with_type preserves mutations" do
+      attribute = Attribute.from_database(:foo, "", Type::Value.new)
+      attribute.value << "1"
+
+      assert_equal 1, attribute.with_type(Type::Integer.new).value
+    end
   end
 end