id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
32594	Signal.disconnect() returns None when passing sender as string	Hugo Cachitas	Hugo Cachitas	"According to the documentation on `Signal.disconnect(receiver=None, sender=None, dispatch_uid=None)`

  The method returns True if a receiver was disconnected and False if not.

I am having this issue where `disconnect()` returns `None` when I specify the sender as a string model reference, i.e., passing `sender=""myapp.MyModel""` instead of `sender=MyModel`.

The sender may be lazily specified as a string as documented in `django.db.models.signals.ModelSignal`.
To achieve this functionality, a `_lazy_method` is implemented where we can find that the return value is not properly set.

{{{
#!python
if isinstance(sender, str):
    apps = apps or Options.default_apps
    apps.lazy_model_operation(partial_method, make_model_tuple(sender))
else:
    return partial_method(sender)
}}} 

I already have a failing test at `tests/signals/tests.py:LazyModelRefTests` that could use your input.

{{{
#!python
@isolate_apps('signals', kwarg_name='apps')
def test_disconnect_return_value(self, apps):
    """"""
    Signal.disconnect() return value should be consistent if we
    use the Model or its string reference.
    """"""

    class Created(models.Model):
        pass

    def receiver(**kwargs):
        pass

    sender = Created
    signals.post_init.connect(receiver, sender=sender, apps=apps)
    self.assertTrue(
        signals.post_init.disconnect(receiver, sender=sender, apps=apps)
    )
    self.assertFalse(
        signals.post_init.disconnect(receiver, sender=sender, apps=apps)
    )

    sender = 'signals.Created'
    signals.post_init.connect(receiver, sender=sender, apps=apps)
    self.assertTrue(
        signals.post_init.disconnect(receiver, sender=sender, apps=apps)
    )
    self.assertFalse(
        signals.post_init.disconnect(receiver, sender=sender, apps=apps)
    )
}}}

"	Bug	closed	Documentation	4.0	Normal	fixed	signals	Alex Hill	Ready for checkin	1	0	0	0	1	0