Possible validator false positive for building:min_level=-1

[nyurik]

relation 2638288 validatior generates this. I don't know if this is an error, but there are almost a thousand of these in taginfo.

Misspelled property value - Value '-1' for key 'building:min_level' looks like '1'. (1)
from
TestError [tester=org.openstreetmap.josm.data.validation.tests.TagChecker@c593f635, code=1212, message=Misspelled property value]

[Don-vip]

It doesn't make sense. According to ​osmwiki:Key:building:min_level :

If a building part does not start at the ground level, building:levels=* should include the number of skipped levels below the building part (i.e the number of levels that would exist if the space between the ground and the bottom of the building part were filled with levels of the typical height for this building). These skipped levels themselves should be tagged as building:min_level=*.

If we look at ​osmwiki:Key:building:levels :

B + C + D counts as building:levels=3
E counts as building:levels:underground=1

So if the majority of buildings have two levels underground, but this one has only one, the correct usage is to tag building:levels:underground=1 instead of building:min_level=-1.

[openstreetmap.org-user-d1g]

... another problem is that with -1 you never know if person counted from 0 or from 1 without additional tag/clarification.

Reason is that ​natural languages differ how to count levels "from the ground".