From 40df67f7043b6953175a9c748ed9f8bc76349857 Mon Sep 17 00:00:00 2001
From: Georg Brandl <georg@python.org>
Date: Thu, 12 Jul 2007 08:05:48 +0000
Subject: [PATCH] Patch #1752270, #1750931: complain if urllib2 add_handler
 called without handler.  (backport from rev. 56293)

---
 Lib/test/test_urllib2.py | 6 ++++++
 Lib/urllib2.py           | 4 ++++
 2 files changed, 10 insertions(+)

diff --git a/Lib/test/test_urllib2.py b/Lib/test/test_urllib2.py
index 5ca760ef4bf..9934d3778bf 100644
--- a/Lib/test/test_urllib2.py
+++ b/Lib/test/test_urllib2.py
@@ -381,6 +381,12 @@ class MockPasswordManager:
 
 class OpenerDirectorTests(unittest.TestCase):
 
+    def test_add_non_handler(self):
+        class NonHandler(object):
+            pass
+        self.assertRaises(TypeError,
+                          OpenerDirector().add_handler, NonHandler())
+
     def test_badly_named_methods(self):
         # test work-around for three methods that accidentally follow the
         # naming conventions for handler methods
diff --git a/Lib/urllib2.py b/Lib/urllib2.py
index 09d7f9c423e..3578e7a0b97 100644
--- a/Lib/urllib2.py
+++ b/Lib/urllib2.py
@@ -298,6 +298,10 @@ class OpenerDirector:
         self.process_request = {}
 
     def add_handler(self, handler):
+        if not hasattr(handler, "add_parent"):
+            raise TypeError("expected BaseHandler instance, got %r" %
+                            type(handler))
+
         added = False
         for meth in dir(handler):
             if meth in ["redirect_request", "do_open", "proxy_open"]: