1 files changed, 46 insertions, 1 deletions
diff --git a/tests/dispatch/tests.py b/tests/dispatch/tests.py
index 18426d8dd1..e91d29abdd 100644
--- a/tests/dispatch/tests.py
+++ b/tests/dispatch/tests.py
@@ -1,7 +1,9 @@
 import weakref
 from types import TracebackType
+from unittest import mock
 
 from django.dispatch import Signal, receiver
+from django.dispatch.dispatcher import _make_id
 from django.test import SimpleTestCase
 from django.test.utils import garbage_collect, override_settings
 
@@ -75,7 +77,15 @@ class DispatcherTests(SimpleTestCase):
         a_signal.disconnect(receiver_1_arg, sender=object)
         self.assertTestIsClean(a_signal)
 
-    def test_garbage_collected(self):
+    def test_unweakrefable_sender(self):
+        sender = object()
+        a_signal.connect(receiver_1_arg, sender=sender)
+        result = a_signal.send(sender=sender, val="test")
+        self.assertEqual(result, [(receiver_1_arg, "test")])
+        a_signal.disconnect(receiver_1_arg, sender=sender)
+        self.assertTestIsClean(a_signal)
+
+    def test_garbage_collected_receiver(self):
         a = Callable()
         a_signal.connect(a.a, sender=self)
         del a
@@ -84,6 +94,41 @@ class DispatcherTests(SimpleTestCase):
         self.assertEqual(result, [])
         self.assertTestIsClean(a_signal)
 
+    def test_garbage_collected_sender(self):
+        signal = Signal()
+
+        class Sender:
+            pass
+
+        def make_id(target):
+            """
+            Simulate id() reuse for distinct senders with non-overlapping
+            lifetimes that would require memory contention to reproduce.
+            """
+            if isinstance(target, Sender):
+                return 0
+            return _make_id(target)
+
+        def first_receiver(attempt, **kwargs):
+            return attempt
+
+        def second_receiver(attempt, **kwargs):
+            return attempt
+
+        with mock.patch("django.dispatch.dispatcher._make_id", make_id):
+            sender = Sender()
+            signal.connect(first_receiver, sender)
+            result = signal.send(sender, attempt="first")
+            self.assertEqual(result, [(first_receiver, "first")])
+
+            del sender
+            garbage_collect()
+
+            sender = Sender()
+            signal.connect(second_receiver, sender)
+            result = signal.send(sender, attempt="second")
+            self.assertEqual(result, [(second_receiver, "second")])
+
     def test_cached_garbaged_collected(self):
         """
         Make sure signal caching sender receivers don't prevent garbage