Fixed #30156 -- Dropped support for SpatiaLite 4.1 and 4.2.

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

 """
 SQL functions reference lists:
-https://www.gaia-gis.it/gaia-sins/spatialite-sql-4.2.1.html
+https://www.gaia-gis.it/gaia-sins/spatialite-sql-4.3.0.html
 """
 from django.contrib.gis.db.backends.base.operations import (
     BaseSpatialOperations,
@@ -9,7 +9,7 @@ from django.contrib.gis.db.backends.spatialite.adapter import SpatiaLiteAdapter
 from django.contrib.gis.db.backends.utils import SpatialOperator
 from django.contrib.gis.db.models import aggregates
 from django.contrib.gis.geos.geometry import GEOSGeometry, GEOSGeometryBase
-from django.contrib.gis.geos.prototypes.io import wkb_r, wkt_r
+from django.contrib.gis.geos.prototypes.io import wkb_r
 from django.contrib.gis.measure import Distance
 from django.core.exceptions import ImproperlyConfigured
 from django.db.backends.sqlite3.operations import DatabaseOperations
@@ -64,9 +64,7 @@ class SpatiaLiteOperations(BaseSpatialOperations, DatabaseOperations):
 
     disallowed_aggregates = (aggregates.Extent3D,)
 
-    @cached_property
-    def select(self):
-        return 'CAST (AsEWKB(%s) AS BLOB)' if self.spatial_version >= (4, 3, 0) else 'AsText(%s)'
+    select = 'CAST (AsEWKB(%s) AS BLOB)'
 
     function_names = {
         'ForcePolygonCW': 'ST_ForceLHR',
@@ -98,8 +96,8 @@ class SpatiaLiteOperations(BaseSpatialOperations, DatabaseOperations):
                     self.connection.settings_dict['NAME'],
                 )
             ) from exc
-        if version < (4, 1, 0):
-            raise ImproperlyConfigured('GeoDjango only supports SpatiaLite versions 4.1.0 and above.')
+        if version < (4, 3, 0):
+            raise ImproperlyConfigured('GeoDjango supports SpatiaLite 4.3.0 and above.')
         return version
 
     def convert_extent(self, box):
@@ -199,21 +197,8 @@ class SpatiaLiteOperations(BaseSpatialOperations, DatabaseOperations):
 
     def get_geometry_converter(self, expression):
         geom_class = expression.output_field.geom_class
-        if self.spatial_version >= (4, 3, 0):
-            read = wkb_r().read
+        read = wkb_r().read
 
-            def converter(value, expression, connection):
-                return None if value is None else GEOSGeometryBase(read(value), geom_class)
-        else:
-            read = wkt_r().read
-            srid = expression.output_field.srid
-            if srid == -1:
-                srid = None
-
-            def converter(value, expression, connection):
-                if value is not None:
-                    geom = GEOSGeometryBase(read(value), geom_class)
-                    if srid:
-                        geom.srid = srid
-                    return geom
+        def converter(value, expression, connection):
+            return None if value is None else GEOSGeometryBase(read(value), geom_class)
         return converter

django/db/models/functions/math.py

@@ -34,12 +34,10 @@ class ATan2(NumericOutputFieldMixin, Func):
     arity = 2
 
     def as_sqlite(self, compiler, connection, **extra_context):
-        if not getattr(connection.ops, 'spatialite', False) or not (
-            (4, 3, 0) <= connection.ops.spatial_version < (5, 0, 0)
-        ):
+        if not getattr(connection.ops, 'spatialite', False) or connection.ops.spatial_version >= (5, 0, 0):
             return self.as_sql(compiler, connection)
         # This function is usually ATan2(y, x), returning the inverse tangent
-        # of y / x, but it's ATan2(x, y) on SpatiaLite >= 4.3.0, < 5.0.0.
+        # of y / x, but it's ATan2(x, y) on SpatiaLite < 5.0.0.
         # Cast integers to float to avoid inconsistent/buggy behavior if the
         # arguments are mixed between integer and float or decimal.
         # https://www.gaia-gis.it/fossil/libspatialite/tktview?name=0f72cca3a2

docs/ref/contrib/gis/install/geolibs.txt

@@ -13,7 +13,7 @@ Program                   Description                           Required
 :doc:`GDAL <../gdal>`     Geospatial Data Abstraction Library   Yes                               2.3, 2.2, 2.1, 2.0, 1.11
 :doc:`GeoIP <../geoip2>`  IP-based geolocation library          No                                2
 `PostGIS`__               Spatial extensions for PostgreSQL     Yes (PostgreSQL only)             2.5, 2.4, 2.3, 2.2, 2.1
-`SpatiaLite`__            Spatial extensions for SQLite         Yes (SQLite only)                 4.3, 4.2, 4.1
+`SpatiaLite`__            Spatial extensions for SQLite         Yes (SQLite only)                 4.3
 ========================  ====================================  ================================  ===================================
 
 Note that older or more recent versions of these libraries *may* also work
@@ -35,8 +35,6 @@ totally fine with GeoDjango. Your mileage may vary.
     PostGIS 2.3.0 2016-09-26
     PostGIS 2.4.0 2017-09-30
     PostGIS 2.5.0 2018-09-23
-    SpatiaLite 4.1.0 2013-06-04
-    SpatiaLite 4.2.0 2014-07-25
     SpatiaLite 4.3.0 2015-09-07
 
 .. note::

docs/ref/contrib/gis/install/index.txt

@@ -61,7 +61,7 @@ Database            Library Requirements            Supported Versions  Notes
 PostgreSQL          GEOS, GDAL, PROJ.4, PostGIS     9.4+                Requires PostGIS.
 MySQL               GEOS, GDAL                      5.6+                Not OGC-compliant; :ref:`limited functionality <mysql-spatial-limitations>`.
 Oracle              GEOS, GDAL                      12.1+               XE not supported.
-SQLite              GEOS, GDAL, PROJ.4, SpatiaLite  3.8.3+              Requires SpatiaLite 4.1+
+SQLite              GEOS, GDAL, PROJ.4, SpatiaLite  3.8.3+              Requires SpatiaLite 4.3+
 ==================  ==============================  ==================  =========================================
 
 See also `this comparison matrix`__ on the OSGeo Wiki for

docs/releases/3.0.txt

@@ -222,6 +222,11 @@ backends.
   ``can_return_ids_from_bulk_insert`` are renamed to
   ``can_return_columns_from_insert`` and ``can_return_rows_from_bulk_insert``.
 
+:mod:`django.contrib.gis`
+-------------------------
+
+* Support for SpatiaLite 4.1 and 4.2 is removed.
+
 Miscellaneous
 -------------