support: greendns: always resolve port

Fixes https://bitbucket.org/eventlet/eventlet/issue/152

eventlet/support/greendns.py

@@ -258,6 +258,7 @@ def getnameinfo(sockaddr, flags):
 
     return (host, port)
 
+
 def is_ipv4_addr(host):
     """is_ipv4_addr returns true if host is a valid IPv4 address in
     dotted quad notation.

tests/greendns_test.py

@@ -0,0 +1,13 @@
+from nose.plugins.skip import SkipTest
+
+
+def test_greendns_getnameinfo_resolve_port():
+    try:
+        from eventlet.support import greendns
+    except ImportError:
+        raise SkipTest('greendns requires package dnspython')
+
+    # https://bitbucket.org/eventlet/eventlet/issue/152
+    _, port1 = greendns.getnameinfo(('127.0.0.1', 80), 0)
+    _, port2 = greendns.getnameinfo(('localhost', 80), 0)
+    assert port1 == port2 == 'http'