Fix DNS resolution by using hostname instead of netloc and strip username and password when comparing against proxy bypass items.

AUTHORS.rst

@@ -182,3 +182,4 @@ Patches and Suggestions
 - Arthur Vigil (`@ahvigil <https://github.com/ahvigil>`_)
 - Nehal J Wani (`@nehaljwani <https://github.com/nehaljwani>`_)
 - Demetrios Bairaktaris (`@DemetriosBairaktaris <https://github.com/demetriosbairaktaris>`_)
+- Darren Dormer (`@ddormer <https://github.com/ddormer>`_)

HISTORY.rst

@@ -17,7 +17,8 @@ dev
 - Fixed issue where loading the default certificate bundle from a zip archive
   would raise an ``IOError``
 - Fixed issue with unexpected ``ImportError`` on windows system which do not support ``winreg`` module
-
+- DNS resolution in proxy bypass no longer includes the username and password in
+  the request. This also fixes the issue of DNS queries failing on macOS.
 
 2.18.4 (2017-08-15)
 +++++++++++++++++++

requests/utils.py

@@ -703,28 +703,31 @@ def should_bypass_proxies(url, no_proxy):
     no_proxy_arg = no_proxy
     if no_proxy is None:
         no_proxy = get_proxy('no_proxy')
-    netloc = urlparse(url).netloc
+    parsed = urlparse(url)
 
     if no_proxy:
         # We need to check whether we match here. We need to see if we match
-        # the end of the netloc, both with and without the port.
+        # the end of the hostname, both with and without the port.
         no_proxy = (
             host for host in no_proxy.replace(' ', '').split(',') if host
         )
 
-        ip = netloc.split(':')[0]
-        if is_ipv4_address(ip):
+        if is_ipv4_address(parsed.hostname):
             for proxy_ip in no_proxy:
                 if is_valid_cidr(proxy_ip):
-                    if address_in_network(ip, proxy_ip):
+                    if address_in_network(parsed.hostname, proxy_ip):
                         return True
-                elif ip == proxy_ip:
+                elif parsed.hostname == proxy_ip:
                     # If no_proxy ip was defined in plain IP notation instead of cidr notation &
                     # matches the IP of the index
                     return True
         else:
+            host_with_port = parsed.hostname
+            if parsed.port:
+                host_with_port += ':{0}'.format(parsed.port)
+
             for host in no_proxy:
-                if netloc.endswith(host) or netloc.split(':')[0].endswith(host):
+                if parsed.hostname.endswith(host) or host_with_port.endswith(host):
                     # The URL does match something in no_proxy, so we don't want
                     # to apply the proxies on this URL.
                     return True
@@ -737,7 +740,7 @@ def should_bypass_proxies(url, no_proxy):
     # legitimate problems.
     with set_environ('no_proxy', no_proxy_arg):
         try:
-            bypass = proxy_bypass(netloc)
+            bypass = proxy_bypass(parsed.hostname)
         except (TypeError, socket.gaierror):
             bypass = False
 

tests/test_utils.py

@@ -614,6 +614,7 @@ def test_urldefragauth(url, expected):
             ('http://172.16.1.1/', True),
             ('http://172.16.1.1:5000/', True),
             ('http://localhost.localdomain:5000/v1.0/', True),
+            ('http://google.com:6000/', True),
             ('http://172.16.1.12/', False),
             ('http://172.16.1.12:5000/', False),
             ('http://google.com:5000/v1.0/', False),
@@ -622,11 +623,31 @@ def test_should_bypass_proxies(url, expected, monkeypatch):
     """Tests for function should_bypass_proxies to check if proxy
     can be bypassed or not
     """
-    monkeypatch.setenv('no_proxy', '192.168.0.0/24,127.0.0.1,localhost.localdomain,172.16.1.1')
-    monkeypatch.setenv('NO_PROXY', '192.168.0.0/24,127.0.0.1,localhost.localdomain,172.16.1.1')
+    monkeypatch.setenv('no_proxy', '192.168.0.0/24,127.0.0.1,localhost.localdomain,172.16.1.1, google.com:6000')
+    monkeypatch.setenv('NO_PROXY', '192.168.0.0/24,127.0.0.1,localhost.localdomain,172.16.1.1, google.com:6000')
     assert should_bypass_proxies(url, no_proxy=None) == expected
 
 
+@pytest.mark.parametrize(
+    'url, expected', (
+            ('http://172.16.1.1/', '172.16.1.1'),
+            ('http://172.16.1.1:5000/', '172.16.1.1'),
+            ('http://user:pass@172.16.1.1', '172.16.1.1'),
+            ('http://user:pass@172.16.1.1:5000', '172.16.1.1'),
+            ('http://hostname/', 'hostname'),
+            ('http://hostname:5000/', 'hostname'),
+            ('http://user:pass@hostname', 'hostname'),
+            ('http://user:pass@hostname:5000', 'hostname'),
+    ))
+def test_should_bypass_proxies_pass_only_hostname(url, expected, mocker):
+    """The proxy_bypass function should be called with a hostname or IP without
+    a port number or auth credentials.
+    """
+    proxy_bypass = mocker.patch('requests.utils.proxy_bypass')
+    should_bypass_proxies(url, no_proxy=None)
+    proxy_bypass.assert_called_once_with(expected)
+
+
 @pytest.mark.parametrize(
     'cookiejar', (
         compat.cookielib.CookieJar(),