[PostGIS] #5685: ST_Node('LINESTRING(0 0, 0 0)') returns GEOMETRYCOLLECTION EMPTY

[PostGIS]

#5685: ST_Node('LINESTRING(0 0,0 0)') returns GEOMETRYCOLLECTION EMPTY
----------------------+---------------------------
  Reporter:  strk     |      Owner:  pramsey
      Type:  defect   |     Status:  new
  Priority:  medium   |  Milestone:  PostGIS 3.5.0
 Component:  postgis  |    Version:  master
Resolution:           |   Keywords:
----------------------+---------------------------
Comment (by strk):

 Commit [8bfdce1c8577ccec4fe870c9a35c196b7dffe24c/git] fixed this specific
 case but single-vertex lines are still turned into empty if they are a
 component of a multilinestring. Even if the single-vertex line would split
 another line:
 {{{
 strk=# select st_astext(st_node('MULTILINESTRING((5 0,5 0),(20 0,10
 0))'));
        st_astext
 -----------------------
  LINESTRING(20 0,10 0)
 (1 row)
 }}}

 It doesn't seem correct

 Note that the underlying GEOSNode does not even touch the input:
 {{{
 DEBUG:  [lwgeom_geos_node.c:lwgeom_node:167] Noded (GEOS): MULTILINESTRING
 ((5 0, 5 0), (20 0, 10 0))
 DEBUG:  [lwgeom_geos_node.c:lwgeom_node:179] LineMerged (GEOS): LINESTRING
 (20 0, 10 0)
 }}}
-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/5685#comment:4>
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