bpo-28728: clarify possible test failure due to ISP (GH-412) (GH-531)
diff --git a/Lib/test/test_socket.py b/Lib/test/test_socket.py
index 97dc3cd..5315d47 100644
--- a/Lib/test/test_socket.py
+++ b/Lib/test/test_socket.py
@@ -803,11 +803,6 @@
self.fail("Error testing host resolution mechanisms. (fqdn: %s, all: %s)" % (fqhn, repr(all_host_names)))
def test_host_resolution(self):
- for addr in ['0.1.1.~1', '1+.1.1.1', '::1q', '::1::2',
- '1:1:1:1:1:1:1:1:1']:
- self.assertRaises(OSError, socket.gethostbyname, addr)
- self.assertRaises(OSError, socket.gethostbyaddr, addr)
-
for addr in [support.HOST, '10.0.0.1', '255.255.255.255']:
self.assertEqual(socket.gethostbyname(addr), addr)
@@ -816,6 +811,21 @@
for host in [support.HOST]:
self.assertIn(host, socket.gethostbyaddr(host)[2])
+ def test_host_resolution_bad_address(self):
+ # These are all malformed IP addresses and expected not to resolve to
+ # any result. But some ISPs, e.g. AWS, may successfully resolve these
+ # IPs.
+ explanation = (
+ "resolving an invalid IP address did not raise OSError; "
+ "can be caused by a broken DNS server"
+ )
+ for addr in ['0.1.1.~1', '1+.1.1.1', '::1q', '::1::2',
+ '1:1:1:1:1:1:1:1:1']:
+ with self.assertRaises(OSError):
+ socket.gethostbyname(addr)
+ with self.assertRaises(OSError, msg=explanation):
+ socket.gethostbyaddr(addr)
+
@unittest.skipUnless(hasattr(socket, 'sethostname'), "test needs socket.sethostname()")
@unittest.skipUnless(hasattr(socket, 'gethostname'), "test needs socket.gethostname()")
def test_sethostname(self):