Added a `QuerySet.ordered` property to check if a queryset is already ordered. Refs #10163.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@10623 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Jacob Kaplan-Moss 2009-04-22 22:16:19 +00:00
parent d463580c1b
commit c00e8d2064
3 changed files with 50 additions and 0 deletions

View File

@ -615,7 +615,24 @@ class QuerySet(object):
clone = self._clone() clone = self._clone()
clone.query.add_immediate_loading(fields) clone.query.add_immediate_loading(fields)
return clone return clone
###################################
# PUBLIC INTROSPECTION ATTRIBUTES #
###################################
def ordered(self):
"""
Returns True if the QuerySet is ordered -- i.e. has an order_by()
clause or a default ordering on the model.
"""
if self.query.extra_order_by or self.query.order_by:
return True
elif self.query.default_ordering and self.query.model._meta.ordering:
return True
else:
return False
ordered = property(ordered)
################### ###################
# PRIVATE METHODS # # PRIVATE METHODS #
################### ###################

View File

@ -268,6 +268,12 @@ There's no way to specify whether ordering should be case sensitive. With
respect to case-sensitivity, Django will order results however your database respect to case-sensitivity, Django will order results however your database
backend normally orders them. backend normally orders them.
.. versionadded:: 1.1
You can tell if a query is ordered or not by checking the
:attr:`QuerySet.ordered` attribute, which will be ``True`` if the
``QuerySet`` has been ordered in any way.
``reverse()`` ``reverse()``
~~~~~~~~~~~~~ ~~~~~~~~~~~~~

View File

@ -0,0 +1,27 @@
import unittest
from models import Tag, Annotation
from django.db.models import Count
class QuerysetOrderedTests(unittest.TestCase):
"""
Tests for the Queryset.ordered attribute.
"""
def test_no_default_or_explicit_ordering(self):
self.assertEqual(Annotation.objects.all().ordered, False)
def test_cleared_default_ordering(self):
self.assertEqual(Tag.objects.all().ordered, True)
self.assertEqual(Tag.objects.all().order_by().ordered, False)
def test_explicit_ordering(self):
self.assertEqual(Annotation.objects.all().order_by('id').ordered, True)
def test_order_by_extra(self):
self.assertEqual(Annotation.objects.all().extra(order_by=['id']).ordered, True)
def test_annotated_ordering(self):
qs = Annotation.objects.annotate(num_notes=Count('notes'))
self.assertEqual(qs.ordered, False)
self.assertEqual(qs.order_by('num_notes').ordered, True)