Fixed #36929 -- Dropped support for GEOS 3.9.

Thanks David Smith for report and Tim Graham for review.

Author: p-r-a-v-i-n

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

@@ -13,7 +13,7 @@ geospatial libraries:
 ==============================  ====================================  ================================  ===================================================
 Program                         Description                           Required                          Supported Versions
 ==============================  ====================================  ================================  ===================================================
-:ref:`GEOS <geos-overview>`     Geometry Engine Open Source           Yes                               3.14, 3.13, 3.12, 3.11, 3.10, 3.9
+:ref:`GEOS <geos-overview>`     Geometry Engine Open Source           Yes                               3.14, 3.13, 3.12, 3.11, 3.10
 `PROJ`_                         Cartographic Projections library      Yes (PostgreSQL and SQLite only)  9.x, 8.x, 7.x, 6.x
 :ref:`GDAL <gdal-overview>`     Geospatial Data Abstraction Library   Yes                               3.12, 3.11, 3.10, 3.9, 3.8, 3.7, 3.6, 3.5, 3.4, 3.3
 :ref:`GeoIP <geoip2-overview>`  IP-based geolocation library          No                                2
@@ -26,7 +26,6 @@ totally fine with GeoDjango. Your mileage may vary.
 
 ..
     Libs release dates:
-    GEOS 3.9.0 2020-12-14
     GEOS 3.10.0 2021-10-20
     GEOS 3.11.0 2022-07-01
     GEOS 3.12.0 2023-06-27

docs/releases/6.1.txt

@@ -383,7 +383,7 @@ backends.
 
 * Support for PostGIS 3.1 is removed.
 
-* Support for GEOS 3.8 is removed.
+* Support for GEOS 3.8 and 3.9 is removed.
 
 * Support for GDAL 3.1 and 3.2 is removed.
 

tests/gis_tests/geos_tests/test_io.py

@@ -9,7 +9,6 @@
     WKTReader,
     WKTWriter,
 )
-from django.contrib.gis.geos.libgeos import geos_version_tuple
 from django.test import SimpleTestCase
 
 
@@ -52,10 +51,7 @@ def test02_wktwriter(self):
     def test_wktwriter_constructor_arguments(self):
         wkt_w = WKTWriter(dim=3, trim=True, precision=3)
         ref = GEOSGeometry("POINT (5.34562 23 1.5)")
-        if geos_version_tuple() > (3, 10):
-            ref_wkt = "POINT Z (5.346 23 1.5)"
-        else:
-            ref_wkt = "POINT Z (5.35 23 1.5)"
+        ref_wkt = "POINT Z (5.346 23 1.5)"
         self.assertEqual(ref_wkt, wkt_w.write(ref).decode())
 
     def test03_wkbreader(self):