BLD/TEST: @network, SkipTest on known errnos

Author: y-p

pandas/util/testing.py

@@ -1099,9 +1099,13 @@ def wrapper(*args, **kwargs):
         except Exception as e:
             errno = getattr(e,'errno',None)
 
-            if not isinstance(e, error_classes) and not errno in skip_errnos:
+            if not isinstance(e, error_classes):
                 raise
 
+            if errno in skip_errnos:
+                raise SkipTest("Skipping test due to known errno"
+                               " and error %s" % e)
+
             if raise_on_error or can_connect(url, error_classes):
                 raise
             else: