From: pgjones <philip.graham.jones@googlemail.com>
Date: Sat, 21 May 2016 15:17:21 +0000 (+0100)
Subject: Change environment cache key construction
X-Git-Tag: 2.9~27^2~5^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1a61008d61cff5b6c95f7b7298e47f2b18685247;p=thirdparty%2Fjinja.git

Change environment cache key construction

Changing from a tuple of the loader ID and template name to a weakref
to the loader and the template name should avoid situations whereby
the loader has changed, yet the cached templates are returned. This
would occur if the id of the new loader matches the old. A weakref is
preferred over a direct reference so that the loader can be garbaged
collected.
---

diff --git a/jinja2/environment.py b/jinja2/environment.py
index 67d05dd9..db51e941 100644
--- a/jinja2/environment.py
+++ b/jinja2/environment.py
@@ -10,6 +10,7 @@
 """
 import os
 import sys
+import weakref
 from functools import reduce, partial
 from jinja2 import nodes
 from jinja2.defaults import BLOCK_START_STRING, \
@@ -769,7 +770,7 @@ class Environment(object):
     def _load_template(self, name, globals):
         if self.loader is None:
             raise TypeError('no loader for this environment specified')
-        cache_key = (id(self.loader), name)
+        cache_key = (weakref.ref(self.loader), name)
         if self.cache is not None:
             template = self.cache.get(cache_key)
             if template is not None and (not self.auto_reload or
diff --git a/tests/test_loader.py b/tests/test_loader.py
index 6b9d9bb4..b916b911 100644
--- a/tests/test_loader.py
+++ b/tests/test_loader.py
@@ -13,6 +13,7 @@ import sys
 import tempfile
 import shutil
 import pytest
+import weakref
 
 from jinja2 import Environment, loaders
 from jinja2._compat import PYPY, PY2
@@ -92,9 +93,10 @@ class TestLoaders():
         assert t2 is env.get_template('two')
         assert t1 is env.get_template('one')
         t3 = env.get_template('three')
-        assert (id(loader), 'one') in env.cache
-        assert (id(loader), 'two') not in env.cache
-        assert (id(loader), 'three') in env.cache
+        loader_ref = weakref.ref(loader)
+        assert (loader_ref, 'one') in env.cache
+        assert (loader_ref, 'two') not in env.cache
+        assert (loader_ref, 'three') in env.cache
 
     def test_cache_loader_change(self):
         loader1 = loaders.DictLoader({'foo': 'one'})