Tagging error when sidewalk:*=separate, but not sidewalk present

[kumakyoo42]

In the list of tagging errors in the README.md an important tagging error is missing: A street is tagged with sidewalk:both=separate (or something similar), but there is no separate sidewalk mapped. This typically causes routers to make detours, because the can't find a way along this street.

Some examples can be found in Troisdorf. (I added notes there.)

[tordans]

Yes, that would be a good additional QA.

Ideally the check would mark the selected street (screenshot) as problematic because it does have separate but is not a continuous separate sidewalk.

Writing this I wonder: I think there is an edge case where we set separate but in fact there is no sidewalk. The centerline just says "the road has no info about this, the info is in a separate geometry". And this sep. geometry may stop and be not there when the sidewalk stops. AFAIK this is valid mapping. At least this is how we treat separate in the street parking schema: A whole way may have parking:left=separate but only parts of it actually have separate areas next to it. The processing has to snap and match those and figure out where the separate actually means no and where it means yes.

Some screenshots from your location: