Fixed #23482 -- Added SingleObjectMixin.query_pk_and_slug

    context_object_name = None

    slug_url_kwarg = 'slug'

    pk_url_kwarg = 'pk'

    query_pk_and_slug = False

    def get_object(self, queryset=None):

        """

            queryset = queryset.filter(pk=pk)

        # Next, try looking up by slug.

        elif slug is not None:

        if slug is not None and (pk is None or self.query_pk_and_slug):

            slug_field = self.get_slug_field()

            queryset = queryset.filter(**{slug_field: slug})

        # If none of those are defined, it's an error.

        else:

        if pk is None and slug is None:

            raise AttributeError("Generic detail view %s must be called with "

                                 "either an object pk or a slug."

                                 % self.__class__.__name__)

        Designates the name of the variable to use in the context.

    .. attribute:: query_pk_and_slug

        .. versionadded:: 1.8

        If ``True``, causes :meth:`get_object()` to perform its lookup using

        both the primary key and the slug. Defaults to ``False``.

        This attribute can help mitigate `insecure direct object reference`_

        attacks. When applications allow access to individual objects by a

        sequential primary key, an attacker could brute-force guess all URLs;

        thereby obtaining a list of all objects in the application. If users

        with access to individual objects should be prevented from obtaining

        this list, setting ``query_pk_and_slug`` to ``True`` will help prevent

        the guessing of URLs as each URL will require two correct,

        non-sequential arguments. Simply using a unique slug may serve the same

        purpose, but this scheme allows you to have non-unique slugs.

        .. _insecure direct object reference: https://www.owasp.org/index.php/Top_10_2013-A4-Insecure_Direct_Object_References

    .. method:: get_object(queryset=None)

        Returns the single object that this view will display. If

        ``queryset`` is provided, that queryset will be used as the

        source of objects; otherwise, :meth:`get_queryset` will be used.

        ``get_object()`` looks for a :attr:`pk_url_kwarg` argument in the

        arguments to the view; if this argument is found, this method performs

        a primary-key based lookup using that value. If this argument is not

        found, it looks for a :attr:`slug_url_kwarg` argument, and performs a

        slug lookup using the :attr:`slug_field`.

        Returns the single object that this view will display. If ``queryset``

        is provided, that queryset will be used as the source of objects;

        otherwise, :meth:`get_queryset` will be used. ``get_object()`` looks

        for a :attr:`pk_url_kwarg` argument in the arguments to the view; if

        this argument is found, this method performs a primary-key based lookup

        using that value. If this argument is not found, it looks for a

        :attr:`slug_url_kwarg` argument, and performs a slug lookup using the

        :attr:`slug_field`.

        .. versionchanged:: 1.8

            When :attr:`query_pk_and_slug` is ``True``, ``get_object()`` will

            perform its lookup using both the primary key and the slug.

    .. method:: get_queryset()

  :attr:`~django.views.generic.list.MultipleObjectMixin.ordering` or overriding

  :meth:`~django.views.generic.list.MultipleObjectMixin.get_ordering()`.

* The new :attr:`SingleObjectMixin.query_pk_and_slug

  <django.views.generic.detail.SingleObjectMixin.query_pk_and_slug>`

  attribute allows changing the behavior of

  :meth:`~django.views.generic.detail.SingleObjectMixin.get_object()`

  so that it'll perform its lookup using both the primary key and the slug.

Internationalization

^^^^^^^^^^^^^^^^^^^^

        self.assertEqual(res.context['author'], Author.objects.get(slug='scott-rosenberg'))

        self.assertTemplateUsed(res, 'generic_views/author_detail.html')

    def test_detail_by_pk_ignore_slug(self):

        author = Author.objects.get(pk=1)

        res = self.client.get('/detail/author/bypkignoreslug/1-roberto-bolano/')

        self.assertEqual(res.status_code, 200)

        self.assertEqual(res.context['object'], author)

        self.assertEqual(res.context['author'], author)

        self.assertTemplateUsed(res, 'generic_views/author_detail.html')

    def test_detail_by_pk_ignore_slug_mismatch(self):

        author = Author.objects.get(pk=1)

        res = self.client.get('/detail/author/bypkignoreslug/1-scott-rosenberg/')

        self.assertEqual(res.status_code, 200)

        self.assertEqual(res.context['object'], author)

        self.assertEqual(res.context['author'], author)

        self.assertTemplateUsed(res, 'generic_views/author_detail.html')

    def test_detail_by_pk_and_slug(self):

        author = Author.objects.get(pk=1)

        res = self.client.get('/detail/author/bypkandslug/1-roberto-bolano/')

        self.assertEqual(res.status_code, 200)

        self.assertEqual(res.context['object'], author)

        self.assertEqual(res.context['author'], author)

        self.assertTemplateUsed(res, 'generic_views/author_detail.html')

    def test_detail_by_pk_and_slug_mismatch_404(self):

        res = self.client.get('/detail/author/bypkandslug/1-scott-rosenberg/')

        self.assertEqual(res.status_code, 404)

    def test_verbose_name(self):

        res = self.client.get('/detail/artist/1/')

        self.assertEqual(res.status_code, 200)

        views.AuthorDetail.as_view()),

    url(r'^detail/author/bycustomslug/(?P<foo>[\w-]+)/$',

        views.AuthorDetail.as_view(slug_url_kwarg='foo')),

    url(r'^detail/author/bypkignoreslug/(?P<pk>[0-9]+)-(?P<slug>[\w-]+)/$',

        views.AuthorDetail.as_view()),

    url(r'^detail/author/bypkandslug/(?P<pk>[0-9]+)-(?P<slug>[\w-]+)/$',

        views.AuthorDetail.as_view(query_pk_and_slug=True)),

    url(r'^detail/author/(?P<pk>[0-9]+)/template_name_suffix/$',

        views.AuthorDetail.as_view(template_name_suffix='_view')),

    url(r'^detail/author/(?P<pk>[0-9]+)/template_name/$',