Fixed a test failure introduced in [14461].

git-svn-id: http://code.djangoproject.com/svn/django/trunk@14462 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/db/models/sql/subqueries.py

@@ -4,7 +4,7 @@ Query subclasses which provide extra functionality beyond simple data retrieval.
 
 from django.core.exceptions import FieldError
 from django.db import connections
-from django.db.models.fields import DateField
+from django.db.models.fields import DateField, FieldDoesNotExist
 from django.db.models.sql.constants import *
 from django.db.models.sql.datastructures import Date
 from django.db.models.sql.expressions import SQLEvaluator
@@ -189,12 +189,17 @@ class DateQuery(Query):
         """
         Converts the query into a date extraction query.
         """
+        try:
             result = self.setup_joins(
                 field_name.split(LOOKUP_SEP),
                 self.get_meta(),
                 self.get_initial_alias(),
                 False
             )
+        except FieldError:
+            raise FieldDoesNotExist("%s has no field named '%s'" % (
+                self.model._meta.object_name, field_name
+            ))
         field = result[0]
         assert isinstance(field, DateField), "%r isn't a DateField." \
                 % field.name