magic-removal: Fixed #1305 -- Added new unit test group for reverse lookup queries over foreign keys. Thanks, Andreas.

git-svn-id: http://code.djangoproject.com/svn/django/branches/magic-removal@2280 bcc190cf-cafb-0310-a4f2-bffc1f526a37

tests/modeltests/reverse_lookup/models.py

@@ -0,0 +1,56 @@
+"""
+25. Reverse lookups
+
+This demonstrates the reverse lookup features of the database API.
+"""
+
+from django.db import models
+
+class User(models.Model):
+    name = models.CharField(maxlength=200)
+    def __repr__(self):
+        return self.name
+
+class Poll(models.Model):
+    question = models.CharField(maxlength=200)
+    creator = models.ForeignKey(User)
+    def __repr__(self):
+        return self.question
+
+class Choice(models.Model):
+    name = models.CharField(maxlength=100)
+    poll = models.ForeignKey(Poll, related_name="poll_choice")
+    related_poll = models.ForeignKey(Poll, related_name="related_choice")
+    def __repr(self):
+        return self.name
+
+API_TESTS = """
+>>> john = User(name="John Doe")
+>>> john.save()
+>>> jim = User(name="Jim Bo")
+>>> jim.save()
+>>> first_poll = Poll(question="What's the first question?", creator=john)
+>>> first_poll.save()
+>>> second_poll = Poll(question="What's the second question?", creator=jim)
+>>> second_poll.save()
+>>> new_choice = Choice(poll=first_poll, related_poll=second_poll, name="This is the answer.")
+>>> new_choice.save()
+
+>>> # Reverse lookups by field name:
+>>> User.objects.get(poll__question__exact="What's the first question?")
+John Doe
+>>> User.objects.get(poll__question__exact="What's the second question?")
+Jim Bo
+
+>>> # Reverse lookups by related_name:
+>>> Poll.objects.get(poll_choice__name__exact="This is the answer.")
+What's the first question?
+>>> Poll.objects.get(related_choice__name__exact="This is the answer.")
+What's the second question?
+
+>>> # If a related_name is given you can't use the field name instead:
+>>> Poll.objects.get(choice__name__exact="This is the answer")
+Traceback (most recent call last):
+    ...
+TypeError: Cannot resolve keyword 'choice' into field
+"""