Fixed some None ref leaks in cPickleCache.c

src/ZODB/tests/testCache.py

@@ -25,6 +25,7 @@ from ZODB.tests.MinPO import MinPO
 from ZODB.utils import p64
 import doctest
 import gc
+import sys
 import threading
 import time
 import transaction
@@ -337,6 +338,8 @@ class CacheErrors(unittest.TestCase):
         def add(key, obj):
             self.cache[key] = obj
 
+        nones = sys.getrefcount(None)
+
         key = p64(2)
         # value isn't persistent
         self.assertRaises(TypeError, add, key, 12)
@@ -360,6 +363,8 @@ class CacheErrors(unittest.TestCase):
         # same object, different keys
         self.assertRaises(ValueError, add, p64(0), o)
 
+        self.assertEqual(sys.getrefcount(None), nones)
+
     def checkTwoCaches(self):
         jar2 = StubDataManager()
         cache2 = PickleCache(jar2)

src/persistent/cPickleCache.c

@@ -242,6 +242,8 @@ scan_gc_items(ccobject *self, int target, PY_LONG_LONG target_bytes)
               Py_DECREF(method);
               if (temp == NULL)
                 error_occurred = 1;
+              else
+                Py_DECREF(temp);
             }
 
           here = placeholder.r_next;
@@ -354,7 +356,6 @@ _invalidate(ccobject *self, PyObject *key)
 {
   static PyObject *_p_invalidate = NULL;
   PyObject *meth, *v;
-  int result;
 
   v = PyDict_GetItem(self->data, key);
   if (v == NULL)
@@ -392,9 +393,10 @@ _invalidate(ccobject *self, PyObject *key)
 
   v = PyObject_CallObject(meth, NULL);
   Py_DECREF(meth);
-  result = v == NULL ? -1 : 0;
+  if (v == NULL)
+    return -1;
   Py_DECREF(v);
-  return result;
+  return 0;
 }
 
 static PyObject *
@@ -1039,9 +1041,11 @@ cc_add_item(ccobject *self, PyObject *key, PyObject *v)
     return -1;
   if (! PyString_Check(oid))
     {
+      Py_DECREF(oid);
       PyErr_Format(PyExc_TypeError,
                    "Cached object oid must be a string, not a %s",
                    oid->ob_type->tp_name);
+      
       return -1;
     }
 

src/persistent/tests/test_PickleCache.py

@@ -109,7 +109,7 @@ Peristent meta classes work too:
 
     """
 
-def cache_invalidate_used_to_leak_None_ref():
+def cache_invalidate_and_minimize_used_to_leak_None_ref():
     """Persistent weak references
 
     >>> import transaction
@@ -127,6 +127,12 @@ def cache_invalidate_used_to_leak_None_ref():
     >>> sys.getrefcount(None) - old
     0
 
+    >>> _ = conn.root.p.keys()
+    >>> old = sys.getrefcount(None)
+    >>> conn._cache.minimize()
+    >>> sys.getrefcount(None) - old
+    0
+
     >>> db.close()
 
     """