[PostGIS] #5786: Side-location conflict: new edge starts in face 42 and ends in face 10

[PostGIS]

#5786: Side-location conflict: new edge starts in face 42 and ends in face 10
--------------------------------+---------------------------
  Reporter:  Lars Aksel Opsahl  |      Owner:  strk
      Type:  defect             |     Status:  new
  Priority:  medium             |  Milestone:  PostGIS 3.5.1
 Component:  topology           |    Version:  master
Resolution:                     |   Keywords:
--------------------------------+---------------------------
Changes (by strk):

 * milestone:  PostGIS 3.6.0 => PostGIS 3.5.1

Comment:

 Further simplification as the problem is with adding the intersection
 point with the incoming line, which can be done independentely:
 {{{
 select NULL FROM topology.DropTopology ('t5786');
 select NULL FROM topology.CreateTopology ('t5786');

 SELECT NULL FROM topology.TopoGeo_addLinestring('t5786', 'LINESTRING(
 11.812075769533624 59.77938755222866,
 11.811862389533625 59.77938237222866
 )');

 SELECT NULL FROM topology.TopoGeo_addLinestring('t5786', 'LINESTRING(
 11.811862389533625 59.77938237222866,
 11.811969079533624 59.77938496222866,
 11.812075769533624 59.77938755222866
 )');

 SELECT * FROM ValidateTopology('t5786');  -- topology is valid here

 BEGIN;

 -- This breaks the topology
 SELECT NULL FROM topology.TopoGeo_addPoint('t5786',
 'POINT(11.812029186127067 59.7793864213727)');

 SELECT * FROM ValidateTopology('t5786');
 }}}

 This is the new experimental edge-merging code that was introduced in
 PostGIS-3.5.0 - in previous versions 3.4 no merge is attempted and thus
 the intersection point always ever splits one of those two edges (edge 2)
 resulting in subsequent error: `SQL/MM Spatial exception - geometry
 crosses edge 1`

 This is to justify setting 3.5 as the milestone, nothing earlier, as if a
 fix is found it should go into the edge-merging code.
-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/5786#comment:4>
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