Disable tests based on mitmproxy while running on PyPy

tests/test_proxy_connect.py

@@ -41,13 +41,8 @@ sys.exit(mitmdump())
                            '--ssl-insecure',
                            ],
                           stdout=PIPE, env=get_testenv())
-        line = self.proc.stdout.read().decode('utf-8')
-        pattern = r'listening at http://([^:]+:\d+)'
-        match = re.search(pattern, line)
-        if not match:
-            raise RuntimeError('Could not find {} in stdout line {}'
-                               .format(repr(pattern), repr(line)))
-        host_port = match.group(1)
+        line = self.proc.stdout.readline().decode('utf-8')
+        host_port = re.search(r'listening at http://([^:]+:\d+)', line).group(1)
         address = 'http://%s:%s@%s' % (self.auth_user, self.auth_pass, host_port)
         return address
 
@@ -64,6 +59,8 @@ def _wrong_credentials(proxy_url):
 
 @skipIf(sys.version_info < (3, 5, 4),
         "requires mitmproxy < 3.0.0, which these tests do not support")
+@skipIf("pypy" in sys.executable,
+        "mitmproxy does not support PyPy")
 class ProxyConnectTestCase(TestCase):
 
     def setUp(self):