ContainsProperly returns true when POINT B is on the boundary of GeometryCollection A

[cuteDen-ECNU]

Consider the following statement:

SELECT ST_ContainsProperly(a1, a2)
FROM ST_GeomFromText('GEOMETRYCOLLECTION(LINESTRING(0 1, 0 0),POINT(0 0))') As a1
,ST_GeomFromText('POINT(0 0)') As a2;
--expected{f}, actual{t}

According to the definition, ContainsProperly returns false when the point of a1 is on the boundary of a2.

Returns true if every point of B lies in the interior of A (or equivalently, no point of B lies in the boundary or exterior of A).
In mathematical terms: ST_ContainsProperly(A, B) ⇔ Int(A) ⋂ B = B

The boundary of a1 (MULTIPOINT((0 1),(0 0), EMPTY)) contains a2, thus, ContainsProperly returns false that is expected.

SELECT ST_AsText(ST_Boundary(a1)), ST_Contains(ST_Boundary(a1), a2)
FROM ST_GeomFromText('GEOMETRYCOLLECTION(LINESTRING(0 1, 0 0),POINT(0 0))') As a1
, ST_GeomFromText('POINT(0 0)') As a2;
--            st_astext           | st_contains 
-- -------------------------------+-------------
--  MULTIPOINT((0 1),(0 0),EMPTY) | t
-- (1 row)

The version is the lastest:
POSTGIS="3.5.0dev 3.4.0rc1-705-g5c3ec8392" [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"

[dr-jts]

This is due to the same issue discussed here. It's due to a limitation in the design of the algorithm for handling GeometryCollections.