From: Ben Darnell <ben@bendarnell.com>
Date: Fri, 16 Dec 2022 19:56:39 +0000 (-0500)
Subject: test: More lenient check for localhost resolver test
X-Git-Tag: v6.3.0b1~19^2~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0105358212a4c4a1374b031b79a141efb734db47;p=thirdparty%2Ftornado.git

test: More lenient check for localhost resolver test

A recent update to pycares appears to have made it return only
an ipv6 address for localhost.
---

diff --git a/tornado/platform/caresresolver.py b/tornado/platform/caresresolver.py
index 962f84f48..1ba45c9ac 100644
--- a/tornado/platform/caresresolver.py
+++ b/tornado/platform/caresresolver.py
@@ -15,14 +15,15 @@ if typing.TYPE_CHECKING:
 class CaresResolver(Resolver):
     """Name resolver based on the c-ares library.
 
-    This is a non-blocking and non-threaded resolver.  It may not produce
-    the same results as the system resolver, but can be used for non-blocking
+    This is a non-blocking and non-threaded resolver.  It may not produce the
+    same results as the system resolver, but can be used for non-blocking
     resolution when threads cannot be used.
 
-    c-ares fails to resolve some names when ``family`` is ``AF_UNSPEC``,
-    so it is only recommended for use in ``AF_INET`` (i.e. IPv4).  This is
-    the default for ``tornado.simple_httpclient``, but other libraries
-    may default to ``AF_UNSPEC``.
+    ``pycares`` will not return a mix of ``AF_INET`` and ``AF_INET6`` when
+    ``family`` is ``AF_UNSPEC``, so it is only recommended for use in
+    ``AF_INET`` (i.e. IPv4).  This is the default for
+    ``tornado.simple_httpclient``, but other libraries may default to
+    ``AF_UNSPEC``.
 
     .. versionchanged:: 5.0
        The ``io_loop`` argument (deprecated since version 4.1) has been removed.
diff --git a/tornado/test/netutil_test.py b/tornado/test/netutil_test.py
index 3911be6a2..df58e1f45 100644
--- a/tornado/test/netutil_test.py
+++ b/tornado/test/netutil_test.py
@@ -44,7 +44,14 @@ class _ResolverTestMixin(object):
     @gen_test
     def test_localhost(self: typing.Any):
         addrinfo = yield self.resolver.resolve("localhost", 80, socket.AF_UNSPEC)
-        self.assertIn((socket.AF_INET, ("127.0.0.1", 80)), addrinfo)
+        # Most of the time localhost resovles to either the ipv4 loopback
+        # address alone, or ipv4+ipv6. But some versions of pycares will only
+        # return the ipv6 version, so we have to check for either one alone.
+        self.assertTrue(
+            ((socket.AF_INET, ("127.0.0.1", 80)) in addrinfo)
+            or ((socket.AF_INET6, ("::1", 80)) in addrinfo),
+            f"loopback address not found in {addrinfo}",
+        )
 
 
 # It is impossible to quickly and consistently generate an error in name
diff --git a/tornado/test/tcpclient_test.py b/tornado/test/tcpclient_test.py
index 2f7bdc104..ecfc82d6f 100644
--- a/tornado/test/tcpclient_test.py
+++ b/tornado/test/tcpclient_test.py
@@ -91,7 +91,11 @@ class TCPClientTest(AsyncTestCase):
     def do_test_connect(self, family, host, source_ip=None, source_port=None):
         port = self.start_server(family)
         stream = yield self.client.connect(
-            host, port, source_ip=source_ip, source_port=source_port
+            host,
+            port,
+            source_ip=source_ip,
+            source_port=source_port,
+            af=family,
         )
         assert self.server is not None
         server_stream = yield self.server.queue.get()
diff --git a/tornado/test/testing_test.py b/tornado/test/testing_test.py
index ef47e97c2..ca48d567a 100644
--- a/tornado/test/testing_test.py
+++ b/tornado/test/testing_test.py
@@ -109,7 +109,7 @@ class AsyncHTTPTestCaseTest(AsyncHTTPTestCase):
     def test_fetch_full_http_url(self):
         # Ensure that self.fetch() recognizes absolute urls and does
         # not transform them into references to our main test server.
-        path = "http://localhost:%d/path" % self.second_port
+        path = "http://127.0.0.1:%d/path" % self.second_port
 
         response = self.fetch(path)
         self.assertEqual(response.request.url, path)
diff --git a/tornado/test/websocket_test.py b/tornado/test/websocket_test.py
index 442b3208d..f90c5f2c0 100644
--- a/tornado/test/websocket_test.py
+++ b/tornado/test/websocket_test.py
@@ -1,5 +1,6 @@
 import asyncio
 import functools
+import socket
 import traceback
 import typing
 import unittest
@@ -9,6 +10,7 @@ from tornado import gen
 from tornado.httpclient import HTTPError, HTTPRequest
 from tornado.locks import Event
 from tornado.log import gen_log, app_log
+from tornado.netutil import Resolver
 from tornado.simple_httpclient import SimpleAsyncHTTPClient
 from tornado.template import DictLoader
 from tornado.testing import AsyncHTTPTestCase, gen_test, bind_unused_port, ExpectLog
@@ -539,6 +541,15 @@ class WebSocketTest(WebSocketBaseTestCase):
     def test_check_origin_invalid_subdomains(self):
         port = self.get_http_port()
 
+        # CaresResolver may return ipv6-only results for localhost, but our
+        # server is only running on ipv4. Test for this edge case and skip
+        # the test if it happens.
+        addrinfo = yield Resolver().resolve("localhost", port)
+        families = set(addr[0] for addr in addrinfo)
+        if socket.AF_INET not in families:
+            self.skipTest("localhost does not resolve to ipv4")
+            return
+
         url = "ws://localhost:%d/echo" % port
         # Subdomains should be disallowed by default.  If we could pass a
         # resolver to websocket_connect we could test sibling domains as well.