Fixed #24615 -- ordering by expression not part of SELECT

Fixed queries where an expression was used in order_by() but the
expression wasn't in the query's select clause (for example the
expression could be masked by .values() call)

Thanks to Trac alias MattBlack85 for the report.

django/contrib/gis/db/backends/base/adapter.py

@@ -12,5 +12,8 @@ class WKTAdapter(object):
             return False
         return self.wkt == other.wkt and self.srid == other.srid
 
+    def __hash__(self):
+        return hash((self.wkt, self.srid))
+
     def __str__(self):
         return self.wkt

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

@@ -28,6 +28,9 @@ class PostGISAdapter(object):
             return False
         return (self.ewkb == other.ewkb) and (self.srid == other.srid)
 
+    def __hash__(self):
+        return hash((self.ewkb, self.srid))
+
     def __str__(self):
         return self.getquoted()
 

django/db/models/sql/compiler.py

@@ -262,10 +262,17 @@ class SQLCompiler(object):
             descending = True if order == 'DESC' else False
 
             if col in self.query.annotation_select:
+                # Reference to expression in SELECT clause
                 order_by.append((
                     OrderBy(Ref(col, self.query.annotation_select[col]), descending=descending),
                     True))
                 continue
+            if col in self.query.annotations:
+                # References to an expression which is masked out of the SELECT clause
+                order_by.append((
+                    OrderBy(self.query.annotations[col], descending=descending),
+                    False))
+                continue
 
             if '.' in field:
                 # This came in through an extra(order_by=...) addition. Pass it

docs/releases/1.8.1.txt

@@ -49,3 +49,7 @@ Bugfixes
   remove usage of referencing views by dotted path in
   :func:`~django.conf.urls.url` which is deprecated in Django 1.8
   (:ticket:`24635`).
+
+* Fixed queries where an expression was referenced in ``order_by()``, but wasn't
+  part of the select clause. An example query is
+  ``qs.annotate(foo=F('field')).values('pk').order_by('foo'))`` (:ticket:`24615`).

tests/gis_tests/distapp/tests.py

@@ -1,6 +1,6 @@
 from __future__ import unicode_literals
 
-from django.contrib.gis.geos import HAS_GEOS
+from django.contrib.gis.geos import HAS_GEOS, Point
 from django.contrib.gis.measure import D  # alias for Distance
 from django.db import connection
 from django.db.models import Q
@@ -383,3 +383,10 @@ class DistanceTest(TestCase):
         z = SouthTexasZipcode.objects.distance(htown.point).area().get(name='78212')
         self.assertIsNone(z.distance)
         self.assertIsNone(z.area)
+
+    @skipUnlessDBFeature("has_distance_method")
+    def test_distance_order_by(self):
+        qs = SouthTexasCity.objects.distance(Point(3, 3)).order_by(
+            'distance'
+        ).values_list('name', flat=True).filter(name__in=('San Antonio', 'Pearland'))
+        self.assertQuerysetEqual(qs, ['San Antonio', 'Pearland'], lambda x: x)