Commit 1fd762c1 authored by Anssi Kääriäinen's avatar Anssi Kääriäinen
Browse files

[1.6.x] Fixed #21428 -- editable GenericRelation regression 

The GenericRelation refactoring removed GenericRelations from
model._meta.many_to_many. This had the side effect of disallowing
editable GenericRelations in ModelForms. Editable GenericRelations
aren't officially supported, but if we don't fix this we don't offer any
upgrade path for those who used the ability to set editable=True
in GenericRelation subclass.

Thanks to Trac alias joshcartme for the report and stephencmd and Loic
for working on this issue.

Backpatch of 0e079e43 from master.
parent e8dea1f3

django/contrib/contenttypes/generic.py

+1 −0
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ class GenericForeignKey(six.with_metaclass(RenameGenericForeignKeyMethods)): 
        self.ct_field = ct_field

        self.fk_field = fk_field

        self.for_concrete_model = for_concrete_model

        self.editable = False



    def contribute_to_class(self, cls, name):

        self.name = name

django/forms/models.py

+10 −5
Original line number Diff line number Diff line
@@ -82,7 +82,12 @@ def save_instance(form, instance, fields=None, fail_message='saved', 
    # Wrap up the saving of m2m data as a function.

    def save_m2m():

        cleaned_data = form.cleaned_data

        for f in opts.many_to_many:

        # Note that for historical reasons we want to include also

        # virtual_fields here. (GenericRelation was previously a fake

        # m2m field).

        for f in opts.many_to_many + opts.virtual_fields:

            if not hasattr(f, 'save_form_data'):

                continue

            if fields and f.name not in fields:

                continue

            if exclude and f.name in exclude:
@@ -118,8 +123,8 @@ def model_to_dict(instance, fields=None, exclude=None): 
    from django.db.models.fields.related import ManyToManyField

    opts = instance._meta

    data = {}

    for f in opts.concrete_fields + opts.many_to_many:

        if not f.editable:

    for f in opts.concrete_fields + opts.virtual_fields + opts.many_to_many:

        if not getattr(f, 'editable', False):

            continue

        if fields and not f.name in fields:

            continue
@@ -168,8 +173,8 @@ def fields_for_model(model, fields=None, exclude=None, widgets=None, 
    field_list = []

    ignored = []

    opts = model._meta

    for f in sorted(opts.concrete_fields + opts.many_to_many):

        if not f.editable:

    for f in sorted(opts.concrete_fields + opts.virtual_fields + opts.many_to_many):

        if not getattr(f, 'editable', False):

            continue

        if fields is not None and not f.name in fields:

            continue

docs/releases/1.6.1.txt

+2 −0
Original line number Diff line number Diff line
@@ -20,3 +20,5 @@ Bug fixes 
* Fixed :class:`~django.contrib.auth.backends.ModelBackend` raising

  ``UnboundLocalError`` if :func:`~django.contrib.auth.get_user_model`

  raised an error (#21439).

* Fixed a regression that prevented editable ``GenericRelation`` subclasses

  from working in ``ModelForms``.

tests/generic_relations_regress/models.py

+10 −1
Original line number Diff line number Diff line
@@ -123,8 +123,17 @@ class Tag(models.Model): 
class Board(models.Model):

    name = models.CharField(primary_key=True, max_length=15)



class SpecialGenericRelation(generic.GenericRelation):

    def __init__(self, *args, **kwargs):

        super(SpecialGenericRelation, self).__init__(*args, **kwargs)

        self.editable = True

        self.save_form_data_calls = 0



    def save_form_data(self, *args, **kwargs):

        self.save_form_data_calls += 1



class HasLinks(models.Model):

    links = generic.GenericRelation(Link)

    links = SpecialGenericRelation(Link)



    class Meta:

        abstract = True

tests/generic_relations_regress/tests.py

+11 −0
Original line number Diff line number Diff line 
from django.db.models import Q

from django.db.utils import IntegrityError

from django.test import TestCase, skipIfDBFeature

from django.forms.models import modelform_factory



from .models import (

    Address, Place, Restaurant, Link, CharLink, TextLink,
@@ -212,3 +213,13 @@ class GenericRelationTests(TestCase): 
        # B would then fail).

        self.assertNotIn(" join ", str(B.objects.exclude(a__flag=True).query).lower())

        self.assertIn("content_type_id", str(B.objects.exclude(a__flag=True).query).lower())



    def test_editable_generic_rel(self):

        GenericRelationForm = modelform_factory(HasLinkThing, fields='__all__')

        form = GenericRelationForm()

        self.assertIn('links', form.fields)

        form = GenericRelationForm({'links': None})

        self.assertTrue(form.is_valid())

        form.save()

        links = HasLinkThing._meta.get_field_by_name('links')[0].field

        self.assertEqual(links.save_form_data_calls, 1)