[PostGIS] #5634: ST_Contains missed one of the pairs

[PostGIS]

#5634: ST_Contains missed one of the pairs
---------------------+---------------------------
 Reporter:  Wenjing  |      Owner:  pramsey
     Type:  defect   |     Status:  new
 Priority:  medium   |  Milestone:  PostGIS 3.4.2
Component:  postgis  |    Version:  3.4.x
 Keywords:           |
---------------------+---------------------------
 Consider the following statements:

 {{{

 DROP table t;
 CREATE table t (id int, geom geometry);
 INSERT INTO t (id, geom) VALUES
 (1,ST_GeomFromText('GEOMETRYCOLLECTION(MULTIPOINT((-60 -50),(-63
 -49)))'));
 INSERT INTO t (id, geom) VALUES
 (2,ST_GeomFromText('GEOMETRYCOLLECTION(MULTIPOINT((-60 -50),(-63
 -49)))'));
 INSERT INTO t (id, geom) VALUES (3,ST_GeomFromText('MULTIPOLYGON(((-60
 -50,-70 -50,-60 -40,-60 -50)))'));
 SELECT a1.id, a2.id FROM t As a1, t As a2 WHERE ST_Contains(a1.geom,
 a2.geom) and a1.id <> a2.id;
 -- actual{1,2; 2,1; 3,1 }
 -- expected{1,2; 2,1; 3,1; 3,2 }

 }}}

 It is noticed that the first geometry and the second geometry are equal,
 which means if the third geometry contains the first one, the third one
 contains the second as well.

 However, when querying the Contains pairs, besides reporting that the
 first and second geometries contain each other (1,2; 2,1), PostGIS just
 answers that the third geometry contains the first geometry (3,1), instead
 of both the first and the second geometries (3,1;3,2), which seems a bug.

 The version is the newest on
 [GitHub](https://trac.osgeo.org/postgis/wiki/GitHub):

 {{{

 POSTGIS="3.5.0dev 3.4.0rc1-818-g6c2e935b6" [EXTENSION] PGSQL="170"
 GEOS="3.13.0dev-CAPI-1.18.0" PROJ="8.2.1
 NETWORK_ENABLED=OFF URL_ENDPOINT=https://cdn.proj.org/
 USER_WRITABLE_DIRECTORY=/tmp/proj DATABASE_PATH=/usr/
 share/proj/proj.db" LIBXML="2.9.13"

 }}}
-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/5634>
PostGIS <http://trac.osgeo.org/postgis/>
The PostGIS Trac is used for bug, enhancement & task tracking, a user and developer wiki, and a view into the subversion code repository of PostGIS project.