Fixed #26421 -- Refactored ModelSignal to use Apps.lazy_model_operation()

2 files changed, 43 insertions, 46 deletions

diff --git a/tests/model_validation/tests.py b/tests/model_validation/tests.py
index b98fd2ddac..0e137af5f2 100644
--- a/tests/model_validation/tests.py
+++ b/tests/model_validation/tests.py
@@ -1,5 +1,5 @@
 from django.core import management
-from django.core.checks import Error, run_checks
+from django.core.checks import Error
 from django.core.checks.model_checks import _check_lazy_references
 from django.db import models
 from django.db.models.signals import post_init
@@ -8,19 +8,6 @@ from django.test.utils import isolate_apps, override_settings
 from django.utils import six
 
 
-class OnPostInit(object):
-    def __call__(self, **kwargs):
-        pass
-
-
-def on_post_init(**kwargs):
-    pass
-
-
-def dummy_function(model):
-    pass
-
-
 @override_settings(
     INSTALLED_APPS=['django.contrib.auth', 'django.contrib.contenttypes'],
     SILENCED_SYSTEM_CHECKS=['fields.W342'],  # ForeignKey(unique=True)
@@ -35,32 +22,6 @@ class ModelValidationTest(SimpleTestCase):
         #       See: https://code.djangoproject.com/ticket/21375
         management.call_command("check", stdout=six.StringIO())
 
-    def test_model_signal(self):
-        unresolved_references = post_init.unresolved_references.copy()
-        post_init.connect(on_post_init, sender='missing-app.Model')
-        post_init.connect(OnPostInit(), sender='missing-app.Model')
-
-        errors = run_checks()
-        expected = [
-            Error(
-                "The 'on_post_init' function was connected to the 'post_init' "
-                "signal with a lazy reference to the 'missing-app.Model' "
-                "sender, which has not been installed.",
-                obj='model_validation.tests',
-                id='signals.E001',
-            ),
-            Error(
-                "An instance of the 'OnPostInit' class was connected to "
-                "the 'post_init' signal with a lazy reference to the "
-                "'missing-app.Model' sender, which has not been installed.",
-                obj='model_validation.tests',
-                id='signals.E001',
-            )
-        ]
-        self.assertEqual(errors, expected)
-
-        post_init.unresolved_references = unresolved_references
-
     @isolate_apps('django.contrib.auth', kwarg_name='apps')
     def test_lazy_reference_checks(self, apps):
 
@@ -70,11 +31,24 @@ class ModelValidationTest(SimpleTestCase):
             class Meta:
                 app_label = "model_validation"
 
+        class DummyClass(object):
+            def __call__(self, **kwargs):
+                pass
+
+            def dummy_method(self):
+                pass
+
+        def dummy_function(*args, **kwargs):
+            pass
+
         apps.lazy_model_operation(dummy_function, ('auth', 'imaginarymodel'))
         apps.lazy_model_operation(dummy_function, ('fanciful_app', 'imaginarymodel'))
 
-        errors = _check_lazy_references(apps)
+        post_init.connect(dummy_function, sender='missing-app.Model', apps=apps)
+        post_init.connect(DummyClass(), sender='missing-app.Model', apps=apps)
+        post_init.connect(DummyClass().dummy_method, sender='missing-app.Model', apps=apps)
 
+        errors = _check_lazy_references(apps)
         expected = [
             Error(
                 "%r contains a lazy reference to auth.imaginarymodel, "
@@ -89,6 +63,22 @@ class ModelValidationTest(SimpleTestCase):
                 id='models.E022',
             ),
             Error(
+                "An instance of class 'DummyClass' was connected to "
+                "the 'post_init' signal with a lazy reference to the sender "
+                "'missing-app.model', but app 'missing-app' isn't installed.",
+                hint=None,
+                obj='model_validation.tests',
+                id='signals.E001',
+            ),
+            Error(
+                "Bound method 'DummyClass.dummy_method' was connected to the "
+                "'post_init' signal with a lazy reference to the sender "
+                "'missing-app.model', but app 'missing-app' isn't installed.",
+                hint=None,
+                obj='model_validation.tests',
+                id='signals.E001',
+            ),
+            Error(
                 "The field model_validation.DummyModel.author was declared "
                 "with a lazy reference to 'model_validation.author', but app "
                 "'model_validation' isn't installed.",
@@ -96,6 +86,13 @@ class ModelValidationTest(SimpleTestCase):
                 obj=DummyModel.author.field,
                 id='fields.E307',
             ),
+            Error(
+                "The function 'dummy_function' was connected to the 'post_init' "
+                "signal with a lazy reference to the sender "
+                "'missing-app.model', but app 'missing-app' isn't installed.",
+                hint=None,
+                obj='model_validation.tests',
+                id='signals.E001',
+            ),
         ]
-
         self.assertEqual(errors, expected)
diff --git a/tests/signals/tests.py b/tests/signals/tests.py
index b02b215958..fd18b2191a 100644
--- a/tests/signals/tests.py
+++ b/tests/signals/tests.py
@@ -267,7 +267,7 @@ class LazyModelRefTest(BaseSignalTest):
         self.received.append(kwargs)
 
     def test_invalid_sender_model_name(self):
-        msg = "Specified sender must either be a model or a model name of the 'app_label.ModelName' form."
+        msg = "Invalid model reference 'invalid'. String model references must be of the form 'app_label.ModelName'."
         with self.assertRaisesMessage(ValueError, msg):
             signals.post_init.connect(self.receiver, sender='invalid')
 
@@ -285,10 +285,10 @@ class LazyModelRefTest(BaseSignalTest):
         finally:
             signals.post_init.disconnect(self.receiver, sender=Book)
 
-    @isolate_apps('signals')
-    def test_not_loaded_model(self):
+    @isolate_apps('signals', kwarg_name='apps')
+    def test_not_loaded_model(self, apps):
         signals.post_init.connect(
-            self.receiver, sender='signals.Created', weak=False
+            self.receiver, sender='signals.Created', weak=False, apps=apps
         )
 
         try: