From d4a3a4b0ca7888ed98e03348af062b0d31d779aa Mon Sep 17 00:00:00 2001
From: Russell Keith-Magee <russell@keith-magee.com>
Date: Sun, 8 Feb 2009 11:14:07 +0000
Subject: [PATCH] Fixed #10199 -- Modified aggregate() calls to clone the base
 query so that the base query can be reused. Thanks to Alex Gaynor for the
 report and patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@9819 bcc190cf-cafb-0310-a4f2-bffc1f526a37
---
 django/db/models/query.py                           | 6 ++++--
 tests/regressiontests/aggregation_regress/models.py | 6 ++++++
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/django/db/models/query.py b/django/db/models/query.py
index e33a858a81..c06a37897e 100644
--- a/django/db/models/query.py
+++ b/django/db/models/query.py
@@ -307,11 +307,13 @@ class QuerySet(object):
         for arg in args:
             kwargs[arg.default_alias] = arg
 
+        query = self.query.clone()
+
         for (alias, aggregate_expr) in kwargs.items():
-            self.query.add_aggregate(aggregate_expr, self.model, alias,
+            query.add_aggregate(aggregate_expr, self.model, alias,
                 is_summary=True)
 
-        return self.query.get_aggregation()
+        return query.get_aggregation()
 
     def count(self):
         """
diff --git a/tests/regressiontests/aggregation_regress/models.py b/tests/regressiontests/aggregation_regress/models.py
index 24de920290..fc2c44b09e 100644
--- a/tests/regressiontests/aggregation_regress/models.py
+++ b/tests/regressiontests/aggregation_regress/models.py
@@ -200,6 +200,12 @@ FieldError: Cannot resolve keyword 'foo' into field. Choices are: authors, conta
 >>> sorted([(b.name, b.authors__age__avg, b.publisher.name, b.contact.name) for b in books])
 [(u'Artificial Intelligence: A Modern Approach', 51.5, u'Prentice Hall', u'Peter Norvig'), (u'Practical Django Projects', 29.0, u'Apress', u'James Bennett'), (u'Python Web Development with Django', 30.3..., u'Prentice Hall', u'Jeffrey Forcier'), (u'Sams Teach Yourself Django in 24 Hours', 45.0, u'Sams', u'Brad Dayley')]
 
+# Regression for #10199 - Aggregate calls clone the original query so the original query can still be used
+>>> books = Book.objects.all()
+>>> _ = books.aggregate(Avg('authors__age'))
+>>> books.all()
+[<Book: Artificial Intelligence: A Modern Approach>, <Book: Paradigms of Artificial Intelligence Programming: Case Studies in Common Lisp>, <Book: Practical Django Projects>, <Book: Python Web Development with Django>, <Book: Sams Teach Yourself Django in 24 Hours>, <Book: The Definitive Guide to Django: Web Development Done Right>]
+
 """
 }