Drop support for plist. Fixes #21

CHANGES.rst

@@ -8,4 +8,5 @@
 
 - First PyPI release.
 - Add support for Python 3.
-- Drop support for externalizing to plists.
+- Drop support for externalizing to plists. See
+  https://github.com/NextThought/nti.externalization/issues/21

docs/conf.py

@@ -169,6 +169,8 @@
     'https://docs.python.org/': None,
     #'https://ntiwref.readthedocs.io/en/latest': None,
     'https://persistent.readthedocs.io/en/latest': None,
+    'https://zopecomponent.readthedocs.io/en/latest': None,
+    'https://zodb.readthedocs.io/en/latest': None,
 }
 
 extlinks = {

src/nti/externalization/configure.zcml

@@ -35,7 +35,6 @@
 
 	<utility factory=".representation.JsonRepresenter" />
 	<utility factory=".representation.YamlRepresenter" />
-	<utility factory=".representation.PlistRepresenter" />
 
 	<!-- Offer to adapt strings to dates -->
 	<!-- TODO: This is a bit ad-hoc. Surely there's a more formal set

src/nti/externalization/externalization.py

@@ -264,12 +264,7 @@ def _to_external_object_state(obj, state, top_level=False, decorate=True,
                 result.append(ext_obj)
             result = state.registry.getAdapter(result,
                                                ILocatedExternalSequence)
-        # PList doesn't support None values, JSON does. The closest
-        # coersion I can think of is False.
-        elif obj is None:
-            if state.coerceNone:
-                result = False
-        else:
+        elif obj is not None:
             # Otherwise, we probably won't be able to JSON-ify it.
             # TODO: Should this live here, or at a higher level where the ultimate
             # external target/use-case is known?
@@ -307,7 +302,6 @@ def _to_external_object_state(obj, state, top_level=False, decorate=True,
 
 
 def toExternalObject(obj,
-                     coerceNone=False,
                      name=_NotGiven,
                      registry=component,
                      catch_components=(),
@@ -677,8 +671,9 @@ def _clean(m):
     "nti.externalization.persistence",
     "NoPickle")
 
-EXT_FORMAT_JSON = 'json'      #: Constant requesting JSON format data
-EXT_FORMAT_PLIST = 'plist'  #: Constant requesting PList (XML) format data
+#: Constant requesting JSON format data
+EXT_FORMAT_JSON = 'json'
+
 
 zope.deferredimport.deprecatedFrom(
     "Import from .representation",

src/nti/externalization/interfaces.py

@@ -270,9 +270,6 @@ class IExternalObjectIO(IExternalObjectRepresenter,
 #: Constant requesting JSON format data
 EXT_REPR_JSON = u'json'
 
-#: Constant requesting PList (XML) format data
-EXT_REPR_PLIST = u'plist'
-
 #: Constant requesting YAML format data
 EXT_REPR_YAML = u'yaml'
 

src/nti/externalization/internalization.py

@@ -304,8 +304,7 @@ def update_from_external_object(containedObject, externalObject,
             ``v`` is the newly-updated value, and ``x`` is the external object used to update ``v``.
     :param callable pre_hook: If given, called with the before update_from_external_object is
             called for every nested object. Signature ``f(k,x)`` where ``k`` is either the key name,
-             or None in the case of a sequence and ``x`` is the external object
-
+            or None in the case of a sequence and ``x`` is the external object
     :return: `containedObject` after updates from `externalObject`
     """
 

src/nti/externalization/representation.py

@@ -3,17 +3,11 @@
 """
 External representation support.
 
-.. $Id$
 """
 
 from __future__ import print_function, absolute_import, division
 __docformat__ = "restructuredtext en"
 
-import collections
-import plistlib
-
-import six
-from six import iteritems
 
 from zope import component
 from zope import interface
@@ -22,7 +16,6 @@
 
 from nti.externalization.interfaces import EXT_REPR_JSON
 from nti.externalization.interfaces import EXT_REPR_YAML
-from nti.externalization.interfaces import EXT_REPR_PLIST
 
 from nti.externalization.interfaces import IExternalObjectIO
 from nti.externalization.interfaces import IExternalObjectRepresenter
@@ -36,9 +29,11 @@
 def to_external_representation(obj, ext_format=EXT_REPR_JSON,
                                name=_NotGiven, registry=component):
     """
-    Transforms (and returns) the `obj` into its external (string) representation.
+    Transforms (and returns) the `obj` into its external (string)
+    representation.
 
-    :param ext_format: One of :const:`EXT_FORMAT_JSON` or :const:`EXT_FORMAT_PLIST`.
+    :param ext_format: One of :const:`nti.externalization.interfaces.EXT_REPR_JSON` or
+        :const:`nti.externalization.interfaces.EXT_REPR_YAML`.
     """
     # It would seem nice to be able to do this in one step during
     # the externalization process itself, but we would wind up traversing
@@ -57,39 +52,6 @@ def to_json_representation(obj):
     return to_external_representation(obj, EXT_REPR_JSON)
 
 
-# Plist
-
-
-
-# The API changed in Python 3.4
-_plist_dump = getattr(plistlib, 'dump', None) or plistlib.writePlist
-_plist_dumps = getattr(plistlib, 'dumps', None) or plistlib.writePlistToString
-
-
-@interface.named(EXT_REPR_PLIST)
-@interface.implementer(IExternalObjectRepresenter)
-class PlistRepresenter(object):
-
-    def stripNoneFromExternal(self, obj):
-        """
-        Given an already externalized object, strips ``None`` values.
-        """
-        if isinstance(obj, (list, tuple)):
-            obj = [self.stripNoneFromExternal(x) for x in obj if x is not None]
-        elif isinstance(obj, collections.Mapping):
-            obj = {k: self.stripNoneFromExternal(v)
-                   for k, v in iteritems(obj)
-                   if v is not None and k is not None}
-        return obj
-
-    def dump(self, obj, fp=None):
-        ext = self.stripNoneFromExternal(obj)
-        if fp is not None:
-            _plist_dump(ext, fp)
-        else:
-            return _plist_dumps(ext)
-
-
 # JSON
 
 
@@ -143,7 +105,7 @@ def load(self, stream):
         # Depending on whether the simplejson C speedups are active, we can still
         # get back a non-unicode string if the object was a naked string. (If the python
         # version is used, it returns unicode; the C version returns str.)
-        if isinstance(value, six.binary_type):
+        if isinstance(value, bytes):
             # we know it's simple ascii or it would have produced unicode
             value = to_unicode(value)
         return value
@@ -199,10 +161,7 @@ def load(self, stream):
 from ZODB.POSException import ConnectionStateError
 
 
-def make_repr(default=None):
-    if default is None:
-        def default(self):
-            return "%s().__dict__.update( %s )" % (self.__class__.__name__, self.__dict__)
+def make_repr(default=lambda self: "%s().__dict__.update( %s )" % (self.__class__.__name__, self.__dict__)):
 
     def __repr__(self):
         try:

src/nti/externalization/tests/test_externalization.py

@@ -25,7 +25,7 @@
 
 import sys
 import json
-import plistlib
+
 import unittest
 
 try:
@@ -43,8 +43,6 @@
 from nti.externalization.datastructures import ExternalizableInstanceDict
 from nti.externalization.datastructures import ExternalizableDictionaryMixin
 
-from nti.externalization.externalization import EXT_FORMAT_JSON
-from nti.externalization.externalization import EXT_FORMAT_PLIST
 
 from nti.externalization.externalization import _manager
 from nti.externalization.externalization import _DevmodeNonExternalizableObjectReplacer
@@ -57,6 +55,7 @@
 from nti.externalization.externalization import to_standard_external_dictionary
 
 from nti.externalization.interfaces import EXT_REPR_YAML
+from nti.externalization.interfaces import EXT_REPR_JSON
 from nti.externalization.interfaces import LocatedExternalList
 from nti.externalization.interfaces import LocatedExternalDict
 
@@ -136,13 +135,8 @@ def test_hookable(self):
     def test_to_external_representation_none_handling(self):
         d = {'a': 1, 'None': None}
         # JSON keeps None
-        assert_that(json.loads(to_external_representation(d, EXT_FORMAT_JSON)),
+        assert_that(json.loads(to_external_representation(d, EXT_REPR_JSON)),
                     is_(d))
-        # PList strips it
-        # The api changed in Python 3.4
-        read_plist = getattr(plistlib, 'loads', getattr(plistlib, 'readPlistFromString', None))
-        assert_that(read_plist(to_external_representation(d, EXT_FORMAT_PLIST)),
-                    is_({'a': 1}))
 
     def test_to_external_representation_yaml(self):
         l = LocatedExternalList()