Fixed #32195 -- Added system check for invalid view in path() and improved error messages.

3 files changed, 38 insertions, 0 deletions

diff --git a/tests/check_framework/test_urls.py b/tests/check_framework/test_urls.py
index 2ef3d5b07f..663c7a299c 100644
--- a/tests/check_framework/test_urls.py
+++ b/tests/check_framework/test_urls.py
@@ -134,6 +134,16 @@ class CheckUrlConfigTests(SimpleTestCase):
         result = check_url_namespaces_unique(None)
         self.assertEqual(result, [])
 
+    @override_settings(ROOT_URLCONF='check_framework.urls.cbv_as_view')
+    def test_check_view_not_class(self):
+        self.assertEqual(check_url_config(None), [
+            Error(
+                "Your URL pattern 'missing_as_view' has an invalid view, pass "
+                "EmptyCBV.as_view() instead of EmptyCBV.",
+                id='urls.E009',
+            ),
+        ])
+
 
 class UpdatedToPathTests(SimpleTestCase):
 
diff --git a/tests/check_framework/urls/cbv_as_view.py b/tests/check_framework/urls/cbv_as_view.py
new file mode 100644
index 0000000000..932a2bfcc9
--- /dev/null
+++ b/tests/check_framework/urls/cbv_as_view.py
@@ -0,0 +1,19 @@
+from django.http import HttpResponse
+from django.urls import path
+from django.views import View
+
+
+class EmptyCBV(View):
+    pass
+
+
+class EmptyCallableView:
+    def __call__(self, request, *args, **kwargs):
+        return HttpResponse()
+
+
+urlpatterns = [
+    path('missing_as_view', EmptyCBV),
+    path('has_as_view', EmptyCBV.as_view()),
+    path('callable_class', EmptyCallableView()),
+]
diff --git a/tests/urlpatterns/tests.py b/tests/urlpatterns/tests.py
index aa593294af..dca9f63086 100644
--- a/tests/urlpatterns/tests.py
+++ b/tests/urlpatterns/tests.py
@@ -5,6 +5,7 @@ from django.core.exceptions import ImproperlyConfigured
 from django.test import SimpleTestCase
 from django.test.utils import override_settings
 from django.urls import NoReverseMatch, Resolver404, path, resolve, reverse
+from django.views import View
 
 from .converters import DynamicConverter
 from .views import empty_view
@@ -146,6 +147,14 @@ class SimplifiedURLTests(SimpleTestCase):
         with self.assertRaisesMessage(TypeError, msg):
             path('articles/', 'invalid_view')
 
+    def test_invalid_view_instance(self):
+        class EmptyCBV(View):
+            pass
+
+        msg = 'view must be a callable, pass EmptyCBV.as_view(), not EmptyCBV().'
+        with self.assertRaisesMessage(TypeError, msg):
+            path('foo', EmptyCBV())
+
     def test_whitespace_in_route(self):
         msg = (
             "URL route 'space/<int:num>/extra/<str:%stest>' cannot contain "