EqualsExact considers 2D and 3D empty geometries as equal

[caspervdw]

Since 3.9, GEOS supports dimensionality of simple empty geometries: LINESTRING Z EMPTY is now actually different from LINESTRING EMPTY.

I would expect that the GEOSEqualsExact function returns false on comparing two empty geometries with different dimensionality. Although they are spatially equal, they have different types. However that is not the case for GEOS main branch.

In pygeos, this detail leads to that some unittests miss the fact that 3D empty geometries are returned for 2D input in for instance SetPrecision. There is currently a workaround in place using GetCoordinateDimension.

[dbaston]

Superseded by ​https://github.com/libgeos/geos/issues/809