Fixed #20642 -- Deprecated `Option.get_(add|change|delete)_permission`.

Those methods were only used by `contrib.admin` internally and exclusively
related to `contrib.auth`. Since they were undocumented but used
in the wild the raised deprecation warning point to an also undocumented
alternative that lives in `contrib.auth`.

Also did some PEP8 and other cleanups in the affected modules.

5 files changed, 106 insertions, 52 deletions

diff --git a/django/contrib/admin/options.py b/django/contrib/admin/options.py
index ce10cf72ba..fd516cb512 100644
--- a/django/contrib/admin/options.py
+++ b/django/contrib/admin/options.py
@@ -4,18 +4,15 @@ from functools import partial, reduce, update_wrapper
 
 from django import forms
 from django.conf import settings
-from django.forms.formsets import all_valid, DELETION_FIELD_NAME
-from django.forms.models import (modelform_factory, modelformset_factory,
-    inlineformset_factory, BaseInlineFormSet, modelform_defines_fields)
-from django.contrib.contenttypes.models import ContentType
+from django.contrib import messages
 from django.contrib.admin import widgets, helpers
 from django.contrib.admin.util import (unquote, flatten_fieldsets, get_deleted_objects,
     model_format_dict, NestedObjects, lookup_needs_distinct)
 from django.contrib.admin import validation
 from django.contrib.admin.templatetags.admin_static import static
 from django.contrib.admin.templatetags.admin_urls import add_preserved_filters
-from django.contrib import messages
-from django.views.decorators.csrf import csrf_protect
+from django.contrib.auth import get_permission_codename
+from django.contrib.contenttypes.models import ContentType
 from django.core.exceptions import PermissionDenied, ValidationError, FieldError
 from django.core.paginator import Paginator
 from django.core.urlresolvers import reverse
@@ -24,6 +21,9 @@ from django.db.models.constants import LOOKUP_SEP
 from django.db.models.related import RelatedObject
 from django.db.models.fields import BLANK_CHOICE_DASH, FieldDoesNotExist
 from django.db.models.sql.constants import QUERY_TERMS
+from django.forms.formsets import all_valid, DELETION_FIELD_NAME
+from django.forms.models import (modelform_factory, modelformset_factory,
+    inlineformset_factory, BaseInlineFormSet, modelform_defines_fields)
 from django.http import Http404, HttpResponseRedirect
 from django.http.response import HttpResponseBase
 from django.shortcuts import get_object_or_404
@@ -39,6 +39,8 @@ from django.utils.text import capfirst, get_text_list
 from django.utils.translation import ugettext as _
 from django.utils.translation import ungettext
 from django.utils.encoding import force_text
+from django.views.decorators.csrf import csrf_protect
+
 
 IS_POPUP_VAR = '_popup'
 
@@ -58,15 +60,15 @@ FORMFIELD_FOR_DBFIELD_DEFAULTS = {
         'form_class': forms.SplitDateTimeField,
         'widget': widgets.AdminSplitDateTime
     },
-    models.DateField:       {'widget': widgets.AdminDateWidget},
-    models.TimeField:       {'widget': widgets.AdminTimeWidget},
-    models.TextField:       {'widget': widgets.AdminTextareaWidget},
-    models.URLField:        {'widget': widgets.AdminURLFieldWidget},
-    models.IntegerField:    {'widget': widgets.AdminIntegerFieldWidget},
+    models.DateField: {'widget': widgets.AdminDateWidget},
+    models.TimeField: {'widget': widgets.AdminTimeWidget},
+    models.TextField: {'widget': widgets.AdminTextareaWidget},
+    models.URLField: {'widget': widgets.AdminURLFieldWidget},
+    models.IntegerField: {'widget': widgets.AdminIntegerFieldWidget},
     models.BigIntegerField: {'widget': widgets.AdminBigIntegerFieldWidget},
-    models.CharField:       {'widget': widgets.AdminTextInputWidget},
-    models.ImageField:      {'widget': widgets.AdminFileWidget},
-    models.FileField:       {'widget': widgets.AdminFileWidget},
+    models.CharField: {'widget': widgets.AdminTextInputWidget},
+    models.ImageField: {'widget': widgets.AdminFileWidget},
+    models.FileField: {'widget': widgets.AdminFileWidget},
 }
 
 csrf_protect_m = method_decorator(csrf_protect)
@@ -352,7 +354,8 @@ class BaseModelAdmin(six.with_metaclass(RenameBaseModelAdminMethods)):
         Can be overridden by the user in subclasses.
         """
         opts = self.opts
-        return request.user.has_perm(opts.app_label + '.' + opts.get_add_permission())
+        codename = get_permission_codename('add', opts)
+        return request.user.has_perm("%s.%s" % (opts.app_label, codename))
 
     def has_change_permission(self, request, obj=None):
         """
@@ -366,7 +369,8 @@ class BaseModelAdmin(six.with_metaclass(RenameBaseModelAdminMethods)):
         request has permission to change *any* object of the given type.
         """
         opts = self.opts
-        return request.user.has_perm(opts.app_label + '.' + opts.get_change_permission())
+        codename = get_permission_codename('change', opts)
+        return request.user.has_perm("%s.%s" % (opts.app_label, codename))
 
     def has_delete_permission(self, request, obj=None):
         """
@@ -380,7 +384,9 @@ class BaseModelAdmin(six.with_metaclass(RenameBaseModelAdminMethods)):
         request has permission to delete *any* object of the given type.
         """
         opts = self.opts
-        return request.user.has_perm(opts.app_label + '.' + opts.get_delete_permission())
+        codename = get_permission_codename('delete', opts)
+        return request.user.has_perm("%s.%s" % (opts.app_label, codename))
+
 
 class ModelAdmin(BaseModelAdmin):
     "Encapsulates all admin options and functionality for a given model."
@@ -608,11 +614,11 @@ class ModelAdmin(BaseModelAdmin):
         """
         from django.contrib.admin.models import LogEntry, ADDITION
         LogEntry.objects.log_action(
-            user_id         = request.user.pk,
-            content_type_id = ContentType.objects.get_for_model(object).pk,
-            object_id       = object.pk,
-            object_repr     = force_text(object),
-            action_flag     = ADDITION
+            user_id=request.user.pk,
+            content_type_id=ContentType.objects.get_for_model(object).pk,
+            object_id=object.pk,
+            object_repr=force_text(object),
+            action_flag=ADDITION
         )
 
     def log_change(self, request, object, message):
@@ -623,12 +629,12 @@ class ModelAdmin(BaseModelAdmin):
         """
         from django.contrib.admin.models import LogEntry, CHANGE
         LogEntry.objects.log_action(
-            user_id         = request.user.pk,
-            content_type_id = ContentType.objects.get_for_model(object).pk,
-            object_id       = object.pk,
-            object_repr     = force_text(object),
-            action_flag     = CHANGE,
-            change_message  = message
+            user_id=request.user.pk,
+            content_type_id=ContentType.objects.get_for_model(object).pk,
+            object_id=object.pk,
+            object_repr=force_text(object),
+            action_flag=CHANGE,
+            change_message=message
         )
 
     def log_deletion(self, request, object, object_repr):
@@ -640,11 +646,11 @@ class ModelAdmin(BaseModelAdmin):
         """
         from django.contrib.admin.models import LogEntry, DELETION
         LogEntry.objects.log_action(
-            user_id         = request.user.pk,
-            content_type_id = ContentType.objects.get_for_model(self.model).pk,
-            object_id       = object.pk,
-            object_repr     = object_repr,
-            action_flag     = DELETION
+            user_id=request.user.pk,
+            content_type_id=ContentType.objects.get_for_model(self.model).pk,
+            object_id=object.pk,
+            object_repr=object_repr,
+            action_flag=DELETION
         )
 
     def action_checkbox(self, obj):
@@ -880,7 +886,7 @@ class ModelAdmin(BaseModelAdmin):
             'has_add_permission': self.has_add_permission(request),
             'has_change_permission': self.has_change_permission(request, obj),
             'has_delete_permission': self.has_delete_permission(request, obj),
-            'has_file_field': True, # FIXME - this should check if form or formsets have a FileField,
+            'has_file_field': True,  # FIXME - this should check if form or formsets have a FileField,
             'has_absolute_url': hasattr(self.model, 'get_absolute_url'),
             'form_url': form_url,
             'opts': opts,
@@ -1050,7 +1056,7 @@ class ModelAdmin(BaseModelAdmin):
         if action_form.is_valid():
             action = action_form.cleaned_data['action']
             select_across = action_form.cleaned_data['select_across']
-            func, name, description = self.get_actions(request)[action]
+            func = self.get_actions(request)[action][0]
 
             # Get the list of selected PKs. If nothing's selected, we can't
             # perform an action on it, so bail. Except we want to perform
@@ -1281,7 +1287,7 @@ class ModelAdmin(BaseModelAdmin):
         actions = self.get_actions(request)
         if actions:
             # Add the action checkboxes if there are any actions available.
-            list_display = ['action_checkbox'] +  list(list_display)
+            list_display = ['action_checkbox'] + list(list_display)
 
         ChangeList = self.get_changelist(request)
         try:
@@ -1430,7 +1436,10 @@ class ModelAdmin(BaseModelAdmin):
             raise PermissionDenied
 
         if obj is None:
-            raise Http404(_('%(name)s object with primary key %(key)r does not exist.') % {'name': force_text(opts.verbose_name), 'key': escape(object_id)})
+            raise Http404(
+                _('%(name)s object with primary key %(key)r does not exist.') %
+                    {'name': force_text(opts.verbose_name), 'key': escape(object_id)}
+            )
 
         using = router.db_for_write(self.model)
 
@@ -1439,7 +1448,7 @@ class ModelAdmin(BaseModelAdmin):
         (deleted_objects, perms_needed, protected) = get_deleted_objects(
             [obj], opts, request.user, self.admin_site, using)
 
-        if request.POST: # The user has already confirmed the deletion.
+        if request.POST:  # The user has already confirmed the deletion.
             if perms_needed:
                 raise PermissionDenied
             obj_display = force_text(obj)
@@ -1457,7 +1466,9 @@ class ModelAdmin(BaseModelAdmin):
                                    (opts.app_label, opts.model_name),
                                    current_app=self.admin_site.name)
                 preserved_filters = self.get_preserved_filters(request)
-                post_url = add_preserved_filters({'preserved_filters': preserved_filters, 'opts': opts}, post_url)
+                post_url = add_preserved_filters(
+                    {'preserved_filters': preserved_filters, 'opts': opts}, post_url
+                )
             else:
                 post_url = reverse('admin:index',
                                    current_app=self.admin_site.name)
@@ -1523,6 +1534,7 @@ class ModelAdmin(BaseModelAdmin):
             "admin/object_history.html"
         ], context, current_app=self.admin_site.name)
 
+
 class InlineModelAdmin(BaseModelAdmin):
     """
     Options for inline editing of ``model`` instances.
@@ -1666,8 +1678,7 @@ class InlineModelAdmin(BaseModelAdmin):
             # to have the change permission for the related model in order to
             # be able to do anything with the intermediate model.
             return self.has_change_permission(request)
-        return request.user.has_perm(
-            self.opts.app_label + '.' + self.opts.get_add_permission())
+        return super(InlineModelAdmin, self).has_add_permission(request)
 
     def has_change_permission(self, request, obj=None):
         opts = self.opts
@@ -1678,8 +1689,8 @@ class InlineModelAdmin(BaseModelAdmin):
                 if field.rel and field.rel.to != self.parent_model:
                     opts = field.rel.to._meta
                     break
-        return request.user.has_perm(
-            opts.app_label + '.' + opts.get_change_permission())
+        codename = get_permission_codename('change', opts)
+        return request.user.has_perm("%s.%s" % (opts.app_label, codename))
 
     def has_delete_permission(self, request, obj=None):
         if self.opts.auto_created:
@@ -1688,8 +1699,7 @@ class InlineModelAdmin(BaseModelAdmin):
             # to have the change permission for the related model in order to
             # be able to do anything with the intermediate model.
             return self.has_change_permission(request, obj)
-        return request.user.has_perm(
-            self.opts.app_label + '.' + self.opts.get_delete_permission())
+        return super(InlineModelAdmin, self).has_delete_permission(request, obj)
 
 
 class StackedInline(InlineModelAdmin):
diff --git a/django/contrib/auth/__init__.py b/django/contrib/auth/__init__.py
index 029193d582..2f620a34fe 100644
--- a/django/contrib/auth/__init__.py
+++ b/django/contrib/auth/__init__.py
@@ -108,7 +108,9 @@ def logout(request):
 
 
 def get_user_model():
-    "Return the User model that is active in this project"
+    """
+    Returns the User model that is active in this project.
+    """
     from django.db.models import get_model
 
     try:
@@ -122,6 +124,10 @@ def get_user_model():
 
 
 def get_user(request):
+    """
+    Returns the user model instance associated with the given request session.
+    If no user is retrieved an instance of `AnonymousUser` is returned.
+    """
     from .models import AnonymousUser
     try:
         user_id = request.session[SESSION_KEY]
@@ -132,3 +138,10 @@ def get_user(request):
     except (KeyError, AssertionError):
         user = AnonymousUser()
     return user
+
+
+def get_permission_codename(action, opts):
+    """
+    Returns the codename of the permission for the specified action.
+    """
+    return '%s_%s' % (action, opts.model_name)
diff --git a/django/contrib/auth/management/__init__.py b/django/contrib/auth/management/__init__.py
index 5c1bfbc515..1f338469f8 100644
--- a/django/contrib/auth/management/__init__.py
+++ b/django/contrib/auth/management/__init__.py
@@ -6,7 +6,8 @@ from __future__ import unicode_literals
 import getpass
 import unicodedata
 
-from django.contrib.auth import models as auth_app, get_user_model
+from django.contrib.auth import (models as auth_app, get_permission_codename,
+    get_user_model)
 from django.core import exceptions
 from django.core.management.base import CommandError
 from django.db import DEFAULT_DB_ALIAS, router
@@ -16,10 +17,6 @@ from django.utils import six
 from django.utils.six.moves import input
 
 
-def _get_permission_codename(action, opts):
-    return '%s_%s' % (action, opts.model_name)
-
-
 def _get_all_permissions(opts, ctype):
     """
     Returns (codename, name) for all permissions in the given opts.
@@ -29,16 +26,18 @@ def _get_all_permissions(opts, ctype):
     _check_permission_clashing(custom, builtin, ctype)
     return builtin + custom
 
+
 def _get_builtin_permissions(opts):
     """
     Returns (codename, name) for all autogenerated permissions.
     """
     perms = []
     for action in ('add', 'change', 'delete'):
-        perms.append((_get_permission_codename(action, opts),
+        perms.append((get_permission_codename(action, opts),
             'Can %s %s' % (action, opts.verbose_name_raw)))
     return perms
 
+
 def _check_permission_clashing(custom, builtin, ctype):
     """
     Check that permissions for a model do not clash. Raises CommandError if
@@ -58,6 +57,7 @@ def _check_permission_clashing(custom, builtin, ctype):
                 (codename, ctype.app_label, ctype.model_class().__name__))
         pool.add(codename)
 
+
 def create_permissions(app, created_models, verbosity, db=DEFAULT_DB_ALIAS, **kwargs):
     try:
         get_model('auth', 'Permission')
diff --git a/django/db/models/options.py b/django/db/models/options.py
index b8a79023e8..ad25de4a3e 100644
--- a/django/db/models/options.py
+++ b/django/db/models/options.py
@@ -414,12 +414,36 @@ class Options(object):
         return cache
 
     def get_add_permission(self):
+        """
+        This method has been deprecated in favor of
+        `django.contrib.auth.get_permission_codename`. refs #20642
+        """
+        warnings.warn(
+            "`Options.get_add_permission` has been deprecated in favor "
+            "of `django.contrib.auth.get_permission_codename`.",
+            PendingDeprecationWarning, stacklevel=2)
         return 'add_%s' % self.model_name
 
     def get_change_permission(self):
+        """
+        This method has been deprecated in favor of
+        `django.contrib.auth.get_permission_codename`. refs #20642
+        """
+        warnings.warn(
+            "`Options.get_change_permission` has been deprecated in favor "
+            "of `django.contrib.auth.get_permission_codename`.",
+            PendingDeprecationWarning, stacklevel=2)
         return 'change_%s' % self.model_name
 
     def get_delete_permission(self):
+        """
+        This method has been deprecated in favor of
+        `django.contrib.auth.get_permission_codename`. refs #20642
+        """
+        warnings.warn(
+            "`Options.get_delete_permission` has been deprecated in favor "
+            "of `django.contrib.auth.get_permission_codename`.",
+            PendingDeprecationWarning, stacklevel=2)
         return 'delete_%s' % self.model_name
 
     def get_all_related_objects(self, local_only=False, include_hidden=False,
diff --git a/docs/releases/1.6.txt b/docs/releases/1.6.txt
index 5d1a37ac53..3d59ce771b 100644
--- a/docs/releases/1.6.txt
+++ b/docs/releases/1.6.txt
@@ -855,6 +855,13 @@ on a widget, you should now define this method on the form field itself.
 ``Model._meta.module_name`` was renamed to ``model_name``. Despite being a
 private API, it will go through a regular deprecation path.
 
+``get_(add|change|delete)_permission`` model _meta methods
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+``Model._meta.get_(add|change|delete)_permission`` methods were deprecated.
+Even if they were not part of the public API they'll also go through
+a regular deprecation path.
+
 ``get_query_set`` and similar methods renamed to ``get_queryset``
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~