Replace use of sweet_pickle in naming, and delete sweet_pickle subpackage

README.rst

@@ -30,9 +30,6 @@ that is commonly needed by many applications
   listener of selected items in an application.
 - **apptools.scripting**: A framework for automatic recording of Python
   scripts.
-- **apptools.sweet_pickle**: Handles class-level versioning, to support
-  loading of saved data that exist over several generations of internal class
-  structures.
 - **apptools.type_manager**: Manages type extensions, including factories
   to generate adapters, and hooks for methods and functions.
 - **apptools.undo**: Supports undoing and scripting application commands.

apptools/naming/object_serializer.py

@@ -18,11 +18,10 @@
 import logging
 from traceback import print_exc
 from os.path import splitext
-#import cPickle
-#import pickle
+import pickle
 
 # Enthought library imports.
-import apptools.sweet_pickle as sweet_pickle
+from apptools.persistence.versioned_unpickler import VersionedUnpickler
 from traits.api import HasTraits, Str
 
 
@@ -56,9 +55,7 @@ def load(self, path):
         f = open(path, 'rb')
         try:
             try:
-                 obj = sweet_pickle.load(f)
-#                obj = cPickle.load(f)
-#                obj = pickle.load(f)
+                 obj = VersionedUnpickler(f).load()
             except Exception as ex:
                 print_exc()
                 logger.exception( "Failed to load pickle file: %s, %s" % (path, ex))
@@ -86,9 +83,7 @@ def save(self, path, obj):
         # Pickle the object.
         f = open(actual_path, 'wb')
         try:
-            sweet_pickle.dump(obj, f, 1)
-#            cPickle.dump(obj, f, 1)
-#            pickle.dump(obj, f, 1)
+            pickle.dump(obj, f, 1)
         except Exception as ex:
             logger.exception( "Failed to pickle into file: %s, %s, object:%s"
                 % (path, ex, obj))

apptools/persistence/versioned_unpickler.py

@@ -1,5 +1,6 @@
 # Standard library imports
-from pickle import *
+from pickle import _Unpickler as Unpickler
+from pickle import UnpicklingError, BUILD
 import logging
 from types import GeneratorType, MethodType
 
@@ -82,6 +83,7 @@ def initialize(self, max_pass):
     # point, we would have the dispatch still pointing to
     # NewPickler.load_build whereas the object being passed in will be an
     # Unpickler instance, causing a TypeError.
+    @classmethod
     def load_build(cls, obj):
         # Just save the instance in the list of objects.
         if isinstance(obj, NewUnpickler):