Ticket #22481: 22481-1.diff

django/contrib/gis/db/backends/postgis/schema.py

@@ -7 +7 @@
     geom_index_ops_nd = 'GIST_GEOMETRY_OPS_ND'
 
     sql_add_geometry_column = "SELECT AddGeometryColumn(%(table)s, %(column)s, %(srid)s, %(geom_type)s, %(dim)s)"
+    sql_drop_geometry_column = "SELECT DropGeometryColumn(%(table)s, %(column)s)"
     sql_alter_geometry_column_not_null = "ALTER TABLE %(table)s ALTER COLUMN %(column)s SET NOT NULL"
     sql_add_spatial_index = "CREATE INDEX %(index)s ON %(table)s USING %(index_type)s (%(column)s %(ops)s)"
 
@@ -70 +71 @@
                 }
             )
         return column_sql
+
+    def remove_field(self, model, field):
+        from django.contrib.gis.db.models.fields import GeometryField
+        if not isinstance(field, GeometryField) or self.connection.ops.spatial_version < (2, 0):
+            super(PostGISSchemaEditor, self).remove_field(model, field)
+
+        self.execute(
+            self.sql_drop_geometry_column % {
+                "table": self.geo_quote_name(model._meta.db_table),
+                "column": self.geo_quote_name(field.column),
+            }
+        )

django/contrib/gis/tests/gis_migrations/migrations/0002_add_linestring_field.py

@@ -18 +18 @@
             field=django.contrib.gis.db.models.fields.LineStringField(srid=4326, null=True, blank=True),
             preserve_default=True,
         ),
+        migrations.RemoveField('Neighborhood', 'geom'),
     ]

django/contrib/gis/tests/gis_migrations/test_commands.py

@@ -30 +30 @@
         field_names = [info.name for info in self.get_table_description(table)]
         self.assertIn(field, field_names)
 
+    def assertFieldNotExists(self, table, field):
+        field_names = [info.name for info in self.get_table_description(table)]
+        self.assertNotIn(field, field_names)
+
     @skipUnless(HAS_SPATIAL_DB, "Spatial db is required.")
     @override_system_checks([])
     @override_settings(MIGRATION_MODULES={"gis": "django.contrib.gis.tests.gis_migrations.migrations"})
@@ -49 +53 @@
         self.assertTableExists("gis_household")
         # Run the migrations to 0002 (adding LineString field)
         call_command("migrate", "gis", "0002", verbosity=0)
-        # Test the new field has been created
+        # Test the new field has been created, and old one removed
         self.assertFieldExists("gis_neighborhood", "path")
+        self.assertFieldNotExists("gis_neighborhood", "geom")
         # Unmigrate everything
         call_command("migrate", "gis", "zero", verbosity=0)
         # Make sure it's all gone