Python 3 preparation: convert dbm keys back from bytes to strings.

The Python 3 dbm module uses bytes for keys and values, converting any
passed in strings to bytes and always returning bytes when keys are
listed or values extracted.  Bytes for values is fine with Roundup
(which uses the marshal module to produce the values stored, which
produces bytes anyway in Python 3), but bytes for keys need converting
back to strings when keys are enumerated.

Author: jsm28

roundup/backends/back_anydbm.py

@@ -25,6 +25,7 @@
 import os, marshal, re, weakref, string, copy, time, shutil, logging
 
 from roundup.anypy.dbm_ import anydbm, whichdb
+from roundup.anypy.strings import b2s
 
 from roundup import hyperdb, date, password, roundupdb, security, support
 from roundup.backends import locking
@@ -675,7 +676,7 @@ def pack(self, pack_before):
             db_type = self.determine_db_type(path)
             db = self.opendb(db_name, 'w')
 
-            for key in db.keys():
+            for key in map(b2s, db.keys()):
                 # get the journal for this db entry
                 journal = marshal.loads(db[key])
                 l = []
@@ -1659,7 +1660,7 @@ def getnodeids(self, db=None, retired=None):
             db = self.db.getclassdb(self.classname)
             must_close = True
         try:
-            res.extend(db.keys())
+            res.extend(map(b2s, db.keys()))
 
             # remove the uncommitted, destroyed nodes
             if self.classname in self.db.destroyednodes: