From 1f5531ae79feff8cf3f77164891e01be7f895a36 Mon Sep 17 00:00:00 2001
From: Ryan Kaskel <dev@ryankaskel.com>
Date: Fri, 16 Sep 2016 18:30:01 +0100
Subject: [PATCH] Fix Django 1.0 middleware function compatibility

---
 debug_toolbar/apps.py     |  7 ++++++-
 tests/middleware.py       |  7 +++++++
 tests/test_integration.py | 16 ++++++++++++++++
 3 files changed, 29 insertions(+), 1 deletion(-)
 create mode 100644 tests/middleware.py

diff --git a/debug_toolbar/apps.py b/debug_toolbar/apps.py
index a49dc6b72..a170c8fa6 100644
--- a/debug_toolbar/apps.py
+++ b/debug_toolbar/apps.py
@@ -1,5 +1,7 @@
 from __future__ import absolute_import, unicode_literals
 
+import inspect
+
 from django.apps import AppConfig
 from django.conf import settings
 from django.core.checks import Error, register
@@ -63,4 +65,7 @@ def is_middleware_class(middleware_class, middleware_path):
         middleware_cls = import_string(middleware_path)
     except ImportError:
         return
-    return issubclass(middleware_cls, middleware_class)
+    return (
+        inspect.isclass(middleware_cls) and
+        issubclass(middleware_cls, middleware_class)
+    )
diff --git a/tests/middleware.py b/tests/middleware.py
new file mode 100644
index 000000000..0b717f332
--- /dev/null
+++ b/tests/middleware.py
@@ -0,0 +1,7 @@
+def simple_middleware(get_response):
+    """
+    Used to test Django 1.10 compatibility.
+    """
+    def middleware(request):
+        return get_response(request)
+    return middleware
diff --git a/tests/test_integration.py b/tests/test_integration.py
index 6e400ae26..e48132297 100644
--- a/tests/test_integration.py
+++ b/tests/test_integration.py
@@ -6,6 +6,7 @@
 import unittest
 from xml.etree import ElementTree as ET
 
+import django
 from django.contrib.staticfiles.testing import StaticLiveServerTestCase
 from django.core.checks import Error, run_checks
 from django.test import RequestFactory, TestCase
@@ -243,3 +244,18 @@ def test_check_gzip_middleware_error(self):
                 ),
             ]
         )
+
+    @override_settings(
+        MIDDLEWARE=[
+            'debug_toolbar.middleware.DebugToolbarMiddleware',
+            'tests.middleware.simple_middleware',
+        ],
+        MIDDLEWARE_CLASSES=None
+    )
+    def test_middleware_factory_functions_supported(self):
+        messages = run_checks()
+
+        if django.VERSION[:2] < (1, 10):
+            self.assertEqual(messages, [])
+        else:
+            self.assertEqual(messages[0].id, '1_10.W001')