Moving from 3.3.3 to 3.4.6 introduces "Cannot use @detail_route or @list_route decorators on method "update" as it is an existing route"

[rolfvandam]

After updating from 3.3.3 to 3.4.6 I get the following error when I initialize my routes:

django.core.exceptions.ImproperlyConfigured: Cannot use @detail_route or @list_route decorators on method "update" as it is an existing route

The code responsible looks like this:

def get_url_patterns(app_name):
    from django.contrib.contenttypes.models import ContentType
    router = DefaultRouter()
    for ct in ContentType.objects.filter(app_label=app_name):
        Model = ct.model_class()
        router.register("editor/"+ct.model, create_view_set(Model))
    return router.urls

The viewsets are automatically generated with type and include a mixin that includes methods like these:

    @detail_route(methods=['put'])
    def update(self, request, pk=None):
    ...

What changed in 3.4.6 that might be causing this?

[xordoquy]

There was a bug (#4229) in 3.3 that allowed this to work.