carried forward from Zope-2_8-branch

lib/python/Products/PluginIndexes/DateIndex/DateIndex.py

@@ -26,6 +26,8 @@ from BTrees.OIBTree import OIBTree
 from DateTime.DateTime import DateTime
 from Globals import DTMLFile
 from OFS.PropertyManager import PropertyManager
+from ZODB.POSException import ConflictError
+from zLOG import LOG, ERROR
 from zope.interface import implements
 
 from Products.PluginIndexes.common import safe_callable
@@ -135,6 +137,16 @@ class DateIndex(UnIndex, PropertyManager):
         if ConvertedDate != oldConvertedDate:
             if oldConvertedDate is not _marker:
                 self.removeForwardIndexEntry(oldConvertedDate, documentId)
+                if ConvertedDate is _marker:
+                    try:
+                        del self._unindex[documentId]
+                    except ConflictError:
+                        raise
+                    except:
+                        LOG('UnIndex', ERROR,
+                            ("Should not happen: ConvertedDate was there,"
+                             " now it's not, for document with id %s" %
+                             documentId))
 
             if ConvertedDate is not _marker:
                 self.insertForwardIndexEntry( ConvertedDate, documentId )

lib/python/Products/PluginIndexes/DateIndex/tests/test_DateIndex.py

@@ -239,6 +239,20 @@ class DI_Tests(unittest.TestCase):
             val = (((yr * 12 + mo) * 31 + dy) * 24 + hr) * 60 + mn
             self.failUnlessEqual(self._index.getEntryForObject(k), val)
 
+    def test_removal(self):
+        """ DateIndex would hand back spurious entries when used as a
+            sort_index, because it previously was not removing entries
+            from the _unindex when indexing an object with a value of
+            None. The catalog consults a sort_index's
+            documentToKeyMap() to build the brains.
+        """
+        values = self._values
+        index = self._index
+        self._populateIndex()
+        self._checkApply(self._int_req, [values[7]])
+        index.index_object(7, None)
+        self.failIf(7 in index.documentToKeyMap().keys())
+
 
 def test_suite():
     suite = unittest.TestSuite()