1 files changed, 22 insertions, 1 deletions
diff --git a/Lib/test/test_fnmatch.py b/Lib/test/test_fnmatch.py
index 482835d..a93558c 100644
--- a/Lib/test/test_fnmatch.py
+++ b/Lib/test/test_fnmatch.py
@@ -3,10 +3,15 @@
 from test import support
 import unittest
 
-from fnmatch import fnmatch, fnmatchcase, translate, filter
+from fnmatch import (fnmatch, fnmatchcase, _MAXCACHE, _cache, _cacheb, purge,
+                        translate, filter)
+
 
 class FnmatchTestCase(unittest.TestCase):
 
+    def tearDown(self):
+        purge()
+
     def check_match(self, filename, pattern, should_match=1, fn=fnmatch):
         if should_match:
             self.assertTrue(fn(filename, pattern),
@@ -60,6 +65,22 @@ class FnmatchTestCase(unittest.TestCase):
         self.check_match(b'test\xff', b'te*\xff')
         self.check_match(b'foo\nbar', b'foo*')
 
+    def test_cache_clearing(self):
+        # check that caches do not grow too large
+        # http://bugs.python.org/issue7846
+
+        # string pattern cache
+        for i in range(_MAXCACHE + 1):
+            fnmatch('foo', '?' * i)
+
+        self.assertLessEqual(len(_cache), _MAXCACHE)
+
+        # bytes pattern cache
+        for i in range(_MAXCACHE + 1):
+            fnmatch(b'foo', b'?' * i)
+        self.assertLessEqual(len(_cacheb), _MAXCACHE)
+
+
 class TranslateTestCase(unittest.TestCase):
 
     def test_translate(self):