Porting to Python 3.2

Removed compatibility_tools (because we aim to Python 2.7 and Python 3.2)
Performed 2to3 and modified
Usage of django.utils.six which adds dependency on Django >= 1.4.2

polymorphic/__init__.py

@@ -6,23 +6,22 @@ Copyright:
 This code and affiliated files are (C) by Bert Constantin and individual contributors.
 Please see LICENSE and AUTHORS for more information.
 """
+from __future__ import absolute_import
 import django
-from polymorphic_model import PolymorphicModel
+from .polymorphic_model import PolymorphicModel
-from manager import PolymorphicManager
+from .manager import PolymorphicManager
-from query import PolymorphicQuerySet
+from .query import PolymorphicQuerySet
-from query_translate import translate_polymorphic_Q_object
+from .query_translate import translate_polymorphic_Q_object
-from showfields import ShowFieldContent, ShowFieldType, ShowFieldTypeAndContent
+from .showfields import ShowFieldContent, ShowFieldType, ShowFieldTypeAndContent
-from showfields import ShowFields, ShowFieldTypes, ShowFieldsAndTypes  # import old names for compatibility
+from .showfields import ShowFields, ShowFieldTypes, ShowFieldsAndTypes  # import old names for compatibility
 
 
 # Monkey-patch Django < 1.5 to allow ContentTypes for proxy models.
-if django.VERSION[:2] < (1, 5): 
+if django.VERSION[:2] < (1, 5):
     from django.contrib.contenttypes.models import ContentTypeManager
-    from django.utils.encoding import smart_unicode
+    from django.utils.encoding import smart_text
 
     def get_for_model(self, model, for_concrete_model=True):
-        from django.utils.encoding import smart_unicode
-
         if for_concrete_model:
             model = model._meta.concrete_model
         elif model._deferred:
@@ -36,7 +35,7 @@ if django.VERSION[:2] < (1, 5):
             ct, created = self.get_or_create(
                 app_label = opts.app_label,
                 model = opts.object_name.lower(),
-                defaults = {'name': smart_unicode(opts.verbose_name_raw)},
+                defaults = {'name': smart_text(opts.verbose_name_raw)},
             )
             self._add_to_cache(self.db, ct)
 

polymorphic/admin.py

@@ -13,7 +13,8 @@ from django.core.urlresolvers import RegexURLResolver
 from django.http import Http404, HttpResponseRedirect
 from django.shortcuts import render_to_response
 from django.template.context import RequestContext
-from django.utils.encoding import force_unicode
+from django.utils import six
+from django.utils.encoding import force_text
 from django.utils.safestring import mark_safe
 from django.utils.translation import ugettext_lazy as _
 
@@ -315,7 +316,7 @@ class PolymorphicParentModelAdmin(admin.ModelAdmin):
         opts = self.model._meta
 
         context = {
-            'title': _('Add %s') % force_unicode(opts.verbose_name),
+            'title': _('Add %s') % force_text(opts.verbose_name),
             'adminform': adminForm,
             'is_popup': "_popup" in request.REQUEST,
             'media': mark_safe(media),
@@ -482,7 +483,7 @@ class PolymorphicChildModelAdmin(admin.ModelAdmin):
         # By not declaring the fields/form in the base class,
         # get_form() will populate the form with all available fields.
         form = self.get_form(request, obj, exclude=exclude)
-        subclass_fields = form.base_fields.keys() + list(self.get_readonly_fields(request, obj))
+        subclass_fields = list(six.iterkeys(form.base_fields)) + list(self.get_readonly_fields(request, obj))
 
         # Find which fields are not part of the common fields.
         for fieldset in self.base_fieldsets:

polymorphic/base.py

@@ -2,6 +2,7 @@
 """ PolymorphicModel Meta Class
     Please see README.rst or DOCS.rst or http://chrisglass.github.com/django_polymorphic/
 """
+from __future__ import absolute_import
 
 import sys
 import inspect
@@ -10,8 +11,8 @@ from django.db import models
 from django.db.models.base import ModelBase
 from django.db.models.manager import ManagerDescriptor
 
-from manager import PolymorphicManager
+from .manager import PolymorphicManager
-from query import PolymorphicQuerySet
+from .query import PolymorphicQuerySet
 
 # PolymorphicQuerySet Q objects (and filter()) support these additional key words.
 # These are forbidden as field names (a descriptive exception is raised)

polymorphic/compatibility_tools.py

@@ -1,91 +0,0 @@
-# -*- coding: utf-8 -*-
-"""
-Compatibility layer for Python 2.4
-==================================
-
-Currently implements:
-
-+ collections.defaultdict
-+ compat_partition (compatibility replacement for str.partition)
-
-"""
-try:
-    assert False
-    from collections import defaultdict
-except:
-    class defaultdict(dict):
-        def __init__(self, default_factory=None, *a, **kw):
-            if (default_factory is not None and
-                not hasattr(default_factory, '__call__')):
-                raise TypeError('first argument must be callable')
-            dict.__init__(self, *a, **kw)
-            self.default_factory = default_factory
-
-        def __getitem__(self, key):
-            try:
-                return dict.__getitem__(self, key)
-            except KeyError:
-                return self.__missing__(key)
-
-        def __missing__(self, key):
-            if self.default_factory is None:
-                raise KeyError(key)
-            self[key] = value = self.default_factory()
-            return value
-
-        def __reduce__(self):
-            if self.default_factory is None:
-                args = tuple()
-            else:
-                args = self.default_factory,
-            return type(self), args, None, None, self.items()
-
-        def copy(self):
-            return self.__copy__()
-
-        def __copy__(self):
-            return type(self)(self.default_factory, self)
-
-        def __deepcopy__(self, memo):
-            import copy
-            return type(self)(self.default_factory, copy.deepcopy(self.items()))
-
-        def __repr__(self):
-            return 'defaultdict(%s, %s)' % (self.default_factory, dict.__repr__(self))
-
-
-if getattr(str, 'partition', None):
-    def compat_partition(s, sep):
-        return s.partition(sep)
-else:
-    """ from:
-    http://mail.python.org/pipermail/python-dev/2005-September/055962.html
-    """
-    def compat_partition(s, sep, at_sep=1):
-        """ Returns a three element tuple, (head, sep, tail) where:
-
-             head + sep + tail == s
-             sep == '' or sep is t
-             bool(sep) == (t in s)       # sep indicates if the string was found
-        """
-        if not isinstance(sep, basestring) or not sep:
-            raise ValueError('partititon argument must be a non-empty string')
-        if at_sep == 0:
-            result = ('', '', s)
-        else:
-            if at_sep > 0:
-                parts = s.split(sep, at_sep)
-                if len(parts) <= at_sep:
-                    result = (s, '', '')
-                else:
-                    result = (sep.join(parts[:at_sep]), sep, parts[at_sep])
-            else:
-                parts = s.rsplit(sep, at_sep)
-                if len(parts) <= at_sep:
-                    result = ('', '', s)
-                else:
-                    result = (parts[0], sep, sep.join(parts[1:]))
-        assert len(result) == 3
-        assert ''.join(result) == s
-        assert result[1] == '' or result[1] is sep
-        return result

polymorphic/manager.py

@@ -2,6 +2,7 @@
 """ PolymorphicManager
     Please see README.rst or DOCS.rst or http://chrisglass.github.com/django_polymorphic/
 """
+from __future__ import unicode_literals
 import warnings
 from django.db import models
 from polymorphic.query import PolymorphicQuerySet
@@ -42,4 +43,4 @@ class PolymorphicManager(models.Manager):
         return getattr(self.get_query_set(), name)
 
     def __unicode__(self):
-        return u'%s (PolymorphicManager) using %s' % (self.__class__.__name__, self.queryset_class.__name__)
+        return '%s (PolymorphicManager) using %s' % (self.__class__.__name__, self.queryset_class.__name__)

polymorphic/polymorphic_model.py

@@ -13,20 +13,22 @@ Copyright:
 This code and affiliated files are (C) by Bert Constantin and individual contributors.
 Please see LICENSE and AUTHORS for more information.
 """
+from __future__ import absolute_import
 
 from django.db import models
 from django.contrib.contenttypes.models import ContentType
 from django import VERSION as django_VERSION
+from django.utils import six
 
-from base import PolymorphicModelBase
+from .base import PolymorphicModelBase
-from manager import PolymorphicManager
+from .manager import PolymorphicManager
-from query_translate import translate_polymorphic_Q_object
+from .query_translate import translate_polymorphic_Q_object
 
 
 ###################################################################################
 ### PolymorphicModel
 
-class PolymorphicModel(models.Model):
+class PolymorphicModel(six.with_metaclass(PolymorphicModelBase, models.Model)):
     """
     Abstract base class that provides polymorphic behaviour
     for any model directly or indirectly derived from it.
@@ -44,7 +46,6 @@ class PolymorphicModel(models.Model):
 
         super(YourClass,self).save(*args,**kwargs)
     """
-    __metaclass__ = PolymorphicModelBase
 
     # for PolymorphicModelBase, so it can tell which models are polymorphic and which are not (duck typing)
     polymorphic_model_marker = True
@@ -168,7 +169,7 @@ class PolymorphicModel(models.Model):
         subclasses_and_superclasses_accessors = self._get_inheritance_relation_fields_and_models()
 
         from django.db.models.fields.related import SingleRelatedObjectDescriptor, ReverseSingleRelatedObjectDescriptor
-        for name, model in subclasses_and_superclasses_accessors.iteritems():
+        for name, model in subclasses_and_superclasses_accessors.items():
             orig_accessor = getattr(self.__class__, name, None)
             if type(orig_accessor) in [SingleRelatedObjectDescriptor, ReverseSingleRelatedObjectDescriptor]:
                 #print >>sys.stderr, '---------- replacing', name, orig_accessor, '->', model

polymorphic/query.py

@@ -2,14 +2,16 @@
 """ QuerySet for PolymorphicModel
     Please see README.rst or DOCS.rst or http://chrisglass.github.com/django_polymorphic/
 """
+from __future__ import absolute_import
 
-from compatibility_tools import defaultdict
+from collections import defaultdict
 
 from django.db.models.query import QuerySet
 from django.contrib.contenttypes.models import ContentType
+from django.utils import six
 
-from query_translate import translate_polymorphic_filter_definitions_in_kwargs, translate_polymorphic_filter_definitions_in_args
+from .query_translate import translate_polymorphic_filter_definitions_in_kwargs, translate_polymorphic_filter_definitions_in_args
-from query_translate import translate_polymorphic_field_path
+from .query_translate import translate_polymorphic_field_path
 
 # chunk-size: maximum number of objects requested per db-request
 # by the polymorphic queryset.iterator() implementation; we use the same chunk size as Django
@@ -90,7 +92,7 @@ class PolymorphicQuerySet(QuerySet):
         Modifies kwargs if needed (these are Aggregate objects, we translate the lookup member variable)"""
         for a in args:
             assert not '___' in a.lookup, 'PolymorphicModel: annotate()/aggregate(): ___ model lookup supported for keyword arguments only'
-        for a in kwargs.values():
+        for a in six.itervalues(kwargs):
             a.lookup = translate_polymorphic_field_path(self.model, a.lookup)
 
     def annotate(self, *args, **kwargs):
@@ -207,12 +209,12 @@ class PolymorphicQuerySet(QuerySet):
                     real_object = transmogrify(real_class, real_object)
 
                 if self.query.aggregates:
-                    for anno_field_name in self.query.aggregates.keys():
+                    for anno_field_name in six.iterkeys(self.query.aggregates):
                         attr = getattr(base_result_objects_by_id[o_pk], anno_field_name)
                         setattr(real_object, anno_field_name, attr)
 
                 if self.query.extra_select:
-                    for select_field_name in self.query.extra_select.keys():
+                    for select_field_name in six.iterkeys(self.query.extra_select):
                         attr = getattr(base_result_objects_by_id[o_pk], select_field_name)
                         setattr(real_object, select_field_name, attr)
 
@@ -223,13 +225,13 @@ class PolymorphicQuerySet(QuerySet):
 
         # set polymorphic_annotate_names in all objects (currently just used for debugging/printing)
         if self.query.aggregates:
-            annotate_names = self.query.aggregates.keys()  # get annotate field list
+            annotate_names = six.iterkeys(self.query.aggregates)  # get annotate field list
             for real_object in resultlist:
                 real_object.polymorphic_annotate_names = annotate_names
 
         # set polymorphic_extra_select_names in all objects (currently just used for debugging/printing)
         if self.query.extra_select:
-            extra_select_names = self.query.extra_select.keys()  # get extra select field list
+            extra_select_names = six.iterkeys(self.query.extra_select)  # get extra select field list
             for real_object in resultlist:
                 real_object.polymorphic_extra_select_names = extra_select_names
 
@@ -264,7 +266,7 @@ class PolymorphicQuerySet(QuerySet):
 
             for i in range(Polymorphic_QuerySet_objects_per_request):
                 try:
-                    o = base_iter.next()
+                    o = next(base_iter)
                     base_result_objects.append(o)
                 except StopIteration:
                     reached_end = True

polymorphic/query_translate.py

@@ -2,11 +2,13 @@
 """ PolymorphicQuerySet support functions
     Please see README.rst or DOCS.rst or http://chrisglass.github.com/django_polymorphic/
 """
+from __future__ import absolute_import
 
 from django.db import models
 from django.contrib.contenttypes.models import ContentType
 from django.db.models import Q
-from compatibility_tools import compat_partition
+
+from functools import reduce
 
 
 ###################################################################################
@@ -124,7 +126,7 @@ def translate_polymorphic_field_path(queryset_model, field_path):
     into modela__modelb__modelc__field3.
     Returns: translated path (unchanged, if no translation needed)
     """
-    classname, sep, pure_field_path = compat_partition(field_path, '___')
+    classname, sep, pure_field_path = field_path.partition('___')
     if not sep:
         return field_path
     assert classname, 'PolymorphicModel: %s: bad field specification' % field_path
@@ -136,7 +138,7 @@ def translate_polymorphic_field_path(queryset_model, field_path):
 
     if '__' in classname:
         # the user has app label prepended to class name via __ => use Django's get_model function
-        appname, sep, classname = compat_partition(classname, '__')
+        appname, sep, classname = classname.partition('__')
         model = models.get_model(appname, classname)
         assert model, 'PolymorphicModel: model %s (in app %s) not found!' % (model.__name__, appname)
         if not issubclass(model, queryset_model):
@@ -211,7 +213,7 @@ def _create_model_filter_Q(modellist, not_instance_of=False):
     if not modellist:
         return None
 
-    from polymorphic_model import PolymorphicModel
+    from .polymorphic_model import PolymorphicModel
 
     if type(modellist) != list and type(modellist) != tuple:
         if issubclass(modellist, PolymorphicModel):

polymorphic/showfields.py

@@ -1,7 +1,7 @@
 # -*- coding: utf-8 -*-
 
 from django.db import models
-
+from django.utils import six
 
 class ShowFieldBase(object):
     """ base class for the ShowField... model mixins, does the work """
@@ -33,12 +33,12 @@ class ShowFieldBase(object):
                 out += content.__class__.__name__
         elif issubclass(field_type, models.ManyToManyField):
             out += '%d' % content.count()
-        elif type(content) in (int, long):
+        elif isinstance(content, six.integer_types):
-            out += unicode(content)
+            out += str(content)
         elif content is None:
             out += 'None'
         else:
-            txt = unicode(content)
+            txt = str(content)
             if len(txt) > self.polymorphic_showfield_max_field_width:
                 txt = txt[:self.polymorphic_showfield_max_field_width - 2] + '..'
             out += '"' + txt + '"'
@@ -58,7 +58,7 @@ class ShowFieldBase(object):
 
             # if this is the standard primary key named "id", print it as we did with older versions of django_polymorphic
             if field.primary_key and field.name == 'id' and type(field) == models.AutoField:
-                out += ' ' + unicode(getattr(self, field.name))
+                out += ' ' + str(getattr(self, field.name))
 
             # otherwise, display it just like all other fields (with correct type, shortened content etc.)
             else:
@@ -108,11 +108,11 @@ class ShowFieldBase(object):
 
         indent = len(self.__class__.__name__) + 5
         indentstr = ''.rjust(indent)
-        out = u''
+        out = ''
         xpos = 0
         possible_line_break_pos = None
 
-        for i in xrange(len(parts)):
+        for i in range(len(parts)):
             new_section, p, separator = parts[i]
             final = (i == len(parts) - 1)
             if not final:
@@ -139,7 +139,7 @@ class ShowFieldBase(object):
             if not new_section:
                 possible_line_break_pos = len(out)
 
-        return u'<' + out + '>'
+        return '<' + out + '>'
 
 
 class ShowFieldType(ShowFieldBase):

polymorphic/templatetags/polymorphic_admin_tags.py

@@ -1,4 +1,5 @@
 from django.template import Library, Node, TemplateSyntaxError
+from django.utils import six
 
 register = Library()
 
@@ -31,7 +32,7 @@ class BreadcrumbScope(Node):
         # Instead, have an assignment tag that inserts that in the template.
         base_opts = self.base_opts.resolve(context)
         new_vars = {}
-        if base_opts and not isinstance(base_opts, basestring):
+        if base_opts and not isinstance(base_opts, six.string_types):
             new_vars = {
                 'app_label': base_opts.app_label,  # What this is all about
                 'opts': base_opts,

polymorphic/tools_for_tests.py

@@ -7,13 +7,13 @@ import uuid
 from django import forms
 from django.db import models
 from django.utils.encoding import smart_unicode
-
+from django.utils import six
 
 class UUIDVersionError(Exception):
     pass
 
 
-class UUIDField(models.CharField):
+class UUIDField(six.with_metaclass(models.SubfieldBase, models.CharField)):
     """Encode and stores a Python uuid.UUID in a manner that is appropriate
     for the given datatabase that we are using.
 
@@ -22,7 +22,6 @@ class UUIDField(models.CharField):
 
     This class supports type 1, 2, 4, and 5 UUID's.
     """
-    __metaclass__ = models.SubfieldBase
 
     _CREATE_COLUMN_TYPES = {
         'postgresql_psycopg2': 'uuid',

setup.py

@@ -29,6 +29,7 @@ setup(
         'Operating System :: OS Independent',
         'Programming Language :: Python',
         'Programming Language :: Python :: 2',
+        'Programming Language :: Python :: 3',
         'Topic :: Software Development :: Libraries :: Python Modules',
     ]
 )