Function S2Polygon.boundaryEquals

Returns true if two polygons have the same boundary. More precisely, this method requires that both polygons have loops with the same cyclic vertex order and the same nesting hierarchy. (This implies that vertices may be cyclically rotated between corresponding loops, and the loop ordering may be different between the two polygons as long as the nesting hierarchy is the same.)

bool boundaryEquals (
  in const(S2Polygon) b
) const;