[Zope-Checkins] CVS: ZODB3/ZODB/tests - testCache.py:1.17.8.2

[Jim Fulton]

Update of /cvs-repository/ZODB3/ZODB/tests
In directory cvs.zope.org:/tmp/cvs-serv23235/src/ZODB/tests

Modified Files:
      Tag: zope3-zodb3-devel-branch
	testCache.py 
Log Message:
Changed a test to remove a non-sensical assertion.

Added a gc.collect and a loud whine (XXX) to another
test to get it to run.


=== ZODB3/ZODB/tests/testCache.py 1.17.8.1 => 1.17.8.2 ===
--- ZODB3/ZODB/tests/testCache.py:1.17.8.1	Fri Jan 23 15:44:25 2004
+++ ZODB3/ZODB/tests/testCache.py	Mon Jan 26 15:37:13 2004
@@ -21,6 +21,7 @@
 import time
 import types
 import unittest
+import gc
 
 import ZODB
 import ZODB.MappingStorage
@@ -178,13 +179,19 @@
         CONNS = 3
         for i in range(CONNS):
             self.noodle_new_connection()
-
+        
         self.assertEquals(self.db.cacheSize(), CACHE_SIZE * CONNS)
         details = self.db.cacheDetailSize()
         self.assertEquals(len(details), CONNS)
         for d in details:
             self.assertEquals(d['ngsize'], CACHE_SIZE)
-            self.assertEquals(d['size'], CACHE_SIZE)
+
+            # The assertion below is non-sensical
+            # The (poorly named) cache size is a target for non-ghosts.
+            # The cache *usually* contains non-ghosts, so that the
+            # size normally exceeds the target size.
+            
+            #self.assertEquals(d['size'], CACHE_SIZE)
 
     def checkDetail(self):
         CACHE_SIZE = 10
@@ -193,6 +200,28 @@
         CONNS = 3
         for i in range(CONNS):
             self.noodle_new_connection()
+
+        gc.collect()
+
+        # XXX The above gc.collect call is necessary to make this test
+        # pass.
+        #
+        # This test then only works because the other of computations
+        # and object accesses in the "noodle" calls is such that the
+        # persistent mapping containing the MinPO objects is
+        # deactivated before the MinPO objects.
+        #
+        # - Without the gc call, the cache will contain ghost MinPOs
+        #   and the check of the MinPO count below will fail. That's 
+        #   because the counts returned by cacheDetail include ghosts.
+        #
+        # - If the mapping object containing the MinPOs isn't
+        #   deactivated, there will be one fewer non-ghost MinPO and
+        #   the test will fail anyway.
+        #
+        # This test really needs to be thought through and documented
+        # better. 
+
 
         for klass, count in self.db.cacheDetail():
             if klass.endswith('MinPO'):