[Zope-Checkins] CVS: ZODB3/ZODB/tests - RevisionStorage.py:1.4.2.7

[Tim Peters]

Update of /cvs-repository/ZODB3/ZODB/tests
In directory cvs.zope.org:/tmp/cvs-serv30700/ZODB/tests

Modified Files:
      Tag: ZODB3-mvcc-2-branch
	RevisionStorage.py 
Log Message:
checkLoadNonCurrent():  Inserted snoozes sufficient so that this test
always passes on Windows (instead of almost always failing).


=== ZODB3/ZODB/tests/RevisionStorage.py 1.4.2.6 => 1.4.2.7 ===
--- ZODB3/ZODB/tests/RevisionStorage.py:1.4.2.6	Tue Nov 25 12:36:25 2003
+++ ZODB3/ZODB/tests/RevisionStorage.py	Mon Dec  1 10:09:21 2003
@@ -14,7 +14,7 @@
 """Check loadSerial() on storages that support historical revisions."""
 
 from ZODB.tests.MinPO import MinPO
-from ZODB.tests.StorageTestBase import zodb_unpickle, zodb_pickle
+from ZODB.tests.StorageTestBase import zodb_unpickle, zodb_pickle, snooze
 from ZODB.utils import p64, u64
 
 ZERO = '\0'*8
@@ -40,14 +40,23 @@
         revs = []
         revid = None
         for i in range(10):
+            # We need to ensure that successive timestamps are at least
+            # two apart, so that a timestamp exists that's unambiguously
+            # between successive timestamps.  Each call to snooze()
+            # guarantees that the next timestamp will be at least one
+            # larger (and probably much more than that) than the previous
+            # one.
+            snooze()
+            snooze()
             revid = self._dostore(oid, revid, data=MinPO(i))
             revs.append(self._storage.loadEx(oid, ""))
-            
+
         prev = u64(revs[0][2])
         for i in range(1, 10):
             tid = revs[i][2]
             cur = u64(tid)
             middle = prev + (cur - prev) / 2
+            assert prev < middle < cur  # else the snooze() trick failed
             prev = cur
             t = self._storage.loadNonCurrent(oid, p64(middle))
             self.assert_(t is not None)
@@ -61,12 +70,12 @@
 
         self.assertRaises(KeyError, self._storage.loadNonCurrent,
                           oid, p64(0))
-        
+
         revid1 = self._dostore(oid, data=MinPO(1))
-        
+
         self.assertEqual(self._storage.loadNonCurrent(oid, p64(0)), None)
         self.assertEqual(self._storage.loadNonCurrent(oid, revid1), None)
-        
+
         cur = p64(u64(revid1) + 1)
         data, serial, start, end = self._storage.loadNonCurrent(oid, cur)
         self.assertEqual(zodb_unpickle(data), MinPO(1))