Fixed #35086 -- Added support for BoundedCircle on Spatialite 5.1+.

Spatialite 5.1 added support for BoundingCircle
(GEOSMinimumBoundingCircle). GEOS 3.7 is required which is lower than
Django's currently supported minmum of 3.8.

https://groups.google.com/g/spatialite-users/c/hAJ2SgitN4M

https://www.gaia-gis.it/gaia-sins/spatialite-sql-5.1.0.html

Author: smithdc1

django/contrib/gis/db/backends/spatialite/operations.py

@@ -66,6 +66,7 @@ class SpatiaLiteOperations(BaseSpatialOperations, DatabaseOperations):
 
     function_names = {
         "AsWKB": "St_AsBinary",
+        "BoundingCircle": "GEOSMinimumBoundingCircle",
         "ForcePolygonCW": "ST_ForceLHR",
         "FromWKB": "ST_GeomFromWKB",
         "FromWKT": "ST_GeomFromText",
@@ -80,9 +81,11 @@ class SpatiaLiteOperations(BaseSpatialOperations, DatabaseOperations):
 
     @cached_property
     def unsupported_functions(self):
-        unsupported = {"BoundingCircle", "GeometryDistance", "IsEmpty", "MemSize"}
+        unsupported = {"GeometryDistance", "IsEmpty", "MemSize"}
         if not self.geom_lib_version():
             unsupported |= {"Azimuth", "GeoHash", "MakeValid"}
+        if self.spatial_version < (5, 1):
+            unsupported |= {"BoundingCircle"}
         return unsupported
 
     @cached_property

django/contrib/gis/db/models/functions.py

@@ -274,6 +274,13 @@ def as_oracle(self, compiler, connection, **extra_context):
             compiler, connection, **extra_context
         )
 
+    def as_sqlite(self, compiler, connection, **extra_context):
+        clone = self.copy()
+        clone.set_source_expressions([self.get_source_expressions()[0]])
+        return super(BoundingCircle, clone).as_sqlite(
+            compiler, connection, **extra_context
+        )
+
 
 class Centroid(OracleToleranceMixin, GeomOutputGeoFunc):
     arity = 1

docs/ref/contrib/gis/db-api.txt

@@ -397,7 +397,7 @@ Function                              PostGIS  Oracle         MariaDB      MySQL
 :class:`AsWKB`                        X        X              X            X           X
 :class:`AsWKT`                        X        X              X            X           X
 :class:`Azimuth`                      X                                                X (LWGEOM/RTTOPO)
-:class:`BoundingCircle`               X        X
+:class:`BoundingCircle`               X        X                                       X (≥ 5.1)
 :class:`Centroid`                     X        X              X            X           X
 :class:`ClosestPoint`                 X                                                X
 :class:`Difference`                   X        X              X            X           X

docs/ref/contrib/gis/functions.txt

@@ -230,13 +230,18 @@ south = ``π``; west = ``3π/2``.
 
 *Availability*: `PostGIS <https://postgis.net/docs/ST_MinimumBoundingCircle.html>`__,
 `Oracle <https://docs.oracle.com/en/database/oracle/oracle-database/21/spatl/
-SDO_GEOM-reference.html#GUID-82A61626-BB64-4793-B53D-A0DBEC91831A>`_
+SDO_GEOM-reference.html#GUID-82A61626-BB64-4793-B53D-A0DBEC91831A>`_,
+SpatiaLite 5.1+
 
 Accepts a single geographic field or expression and returns the smallest circle
 polygon that can fully contain the geometry.
 
 The ``num_seg`` parameter is used only on PostGIS.
 
+.. versionchanged:: 5.1
+
+    SpatiaLite 5.1+ support was added.
+
 ``Centroid``
 ============
 

docs/releases/5.1.txt

@@ -53,7 +53,8 @@ Minor features
 :mod:`django.contrib.gis`
 ~~~~~~~~~~~~~~~~~~~~~~~~~
 
-* ...
+* :class:`~django.contrib.gis.db.models.functions.BoundingCircle` is now
+  supported on SpatiaLite 5.1+.
 
 :mod:`django.contrib.messages`
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

tests/gis_tests/geoapp/test_functions.py

@@ -258,7 +258,12 @@ def circle_num_points(num_seg):
             # num_seg is the number of segments per quarter circle.
             return (4 * num_seg) + 1
 
-        expected_areas = (169, 136) if connection.ops.postgis else (171, 126)
+        if connection.ops.postgis:
+            expected_areas = (169, 136)
+        elif connection.ops.spatialite:
+            expected_areas = (168, 135)
+        else:  # Oracle.
+            expected_areas = (171, 126)
         qs = Country.objects.annotate(
             circle=functions.BoundingCircle("mpoly")
         ).order_by("name")