Jonas Jenwald d9fac34596 Ensure that the shadow helper function is passed a valid property (PR 14152 follow-up)
Trying to shadow a non-existent property is always an implementation mistake, since it leads to the `shadow`-call not having any effect.

In PR 14152 I overlooked the fact that it's fairly easy to enforce this during development/testing, since that can help catch e.g. simple spelling bugs.
2021-12-04 10:07:21 +01:00
..