geomfn: st_simplify with NaN causes node to crash

[rafiss]

This query causes the node to crash without leaving any logs behind.

SELECT st_simplify('0104000000020000000101000000AC885A457886F9C1C9EEF30F7308F3C101010000007411E55B3F66EDC10BBEFA0ABF45F0C1':::GEOMETRY, 'nan':::FLOAT8);

It works on PostGIS though

postgres@localhost:postgres> SELECT st_simplify('0104000000020000000101000000AC885A457886F9C1C9EEF30F7308F3C101010000007411E55B3F66EDC10BBEFA0ABF45F0C1'::GEOMETRY, 'NaN'::FLOAT8)
+--------------------------------------------------------------------------------------------------------+
| st_simplify                                                                                            |
|--------------------------------------------------------------------------------------------------------|
| 0104000000020000000101000000AC885A457886F9C1C9EEF30F7308F3C101010000007411E55B3F66EDC10BBEFA0ABF45F0C1 |
+--------------------------------------------------------------------------------------------------------+
SELECT 1

postgres@localhost:postgres> SELECT st_astext(st_simplify('0104000000020000000101000000AC885A457886F9C1C9EEF30F7308F3C101010000007411E55B3F66EDC10BBEFA0ABF45F0C1'::GEOMETRY,
 'NaN'::FLOAT8))
+-----------------------------------------------------------------------------------+
| st_astext                                                                         |
|-----------------------------------------------------------------------------------|
| MULTIPOINT(-6851888213.65837 -5109133567.2458,-3945921247.15838 -4368101551.6714) |
+-----------------------------------------------------------------------------------+
SELECT 1

cc @otan @andyyang890

[otan]

it works in PostGIS because they a) special case points to return themselves and b) have their own algorithm for simplifying from what i can tell.

we're relying on GEOS instead which does not deliver the goods.

We should make the following changes:
a) Simplify with points/multipoints should return themselves (use ShapeType2D() to determine shape type)
b) Simplify with NaN should return themselves.

This can be done before the check to GEOS here:

cockroach/pkg/geo/geomfn/topology_operations.go

Lines 98 to 101 in 3687e56

	func Simplify(g geo.Geometry, tolerance float64) (geo.Geometry, error) {
	simplifiedEWKB, err := geos.Simplify(g.EWKB(), tolerance)
	if err != nil {
	return geo.Geometry{}, err

With tests added here:

cockroach/pkg/geo/geomfn/topology_operations_test.go

Lines 203 to 209 in 3687e56

	func TestSimplify(t *testing.T) {
	testCases := []struct {
	wkt string
	tolerance float64
	expected string
	}{
	{

[techytoes]

Hey @rafiss, can I pick this up?

[rafiss]

@techytoes sure, please do! @otan's directions above should let you work on this but let me know if you are stuck