is_in does not find surrounding areas for some input sets containing redundant nodes

[Ecumenopolis]

Example:

Nodes 151615580 and 151591244 have the same coordinates in Tekamah, Nebraska.

These two query return the same output set, consisting of one closed way and seven areas.

node(id:151615580); is_in; out ids;
node(id:151591244); is_in; out ids;

But if they are both in the input set, the output set contain only the way -- the relation-based areas aren't found.

node(id:151615580,151591244); is_in; out ids;

[mmd-osm]

This seems to be caused by two nodes having exactly the same coordinates. Using some close by nodes returns the expected result.

node(id:151591244,133114675);is_in; out ids;

https://github.com/drolbr/Overpass-API/blob/master/src/overpass_api/statements/coord_query.cc#L188-L194 might need some additional logic to remove these duplicates.

Entries are removed by: https://github.com/drolbr/Overpass-API/blob/master/src/overpass_api/statements/coord_query.cc#L297

Removing duplicate lat/lon values would help. Maybe there's a better way to fix it.

[drolbr]

Thank you for reporting this bug.