Fix support newbytes from future

Previously python2 code using python-future to backport the py3 bytes
behavior would trigger the following exception:

code:

  from builtins import bytes as newbytes
  from pymemcache.client.base import Client
  client = Client(('localhost', 11211))
  client.set(newbytes('key'), 'value')

  Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
    File "/usr/local/lib/python2.7/site-packages/pymemcache/client/base.py", line 297, in set
      return self._store_cmd(b'set', key, expire, noreply, value)
    File "/usr/local/lib/python2.7/site-packages/pymemcache/client/base.py", line 770, in _store_cmd
      key = self.check_key(key)
    File "/usr/local/lib/python2.7/site-packages/pymemcache/client/base.py", line 251, in check_key
      key_prefix=self.key_prefix)
    File "/usr/local/lib/python2.7/site-packages/pymemcache/client/base.py", line 91, in _check_key
      key = key.encode('ascii')
    File "/usr/local/lib/python2.7/site-packages/future/types/newbytes.py", line 381, in __getattribute__
      raise AttributeError("encode method has been disabled in newbytes")
  AttributeError: encode method has been disabled in newbytes

Add a test case for this and fix.

1 files changed, 4 insertions, 1 deletions

diff --git a/pymemcache/client/base.py b/pymemcache/client/base.py
index 6e9de0f..846adda 100644
--- a/pymemcache/client/base.py
+++ b/pymemcache/client/base.py
@@ -88,7 +88,10 @@ def _check_key(key, allow_unicode_keys, key_prefix=b''):
             key = key.encode('utf8')
     elif isinstance(key, VALID_STRING_TYPES):
         try:
-            key = key.encode('ascii')
+            if isinstance(key, bytes):
+                key = key.decode().encode('ascii')
+            else:
+                key = key.encode('ascii')
         except (UnicodeEncodeError, UnicodeDecodeError):
             raise MemcacheIllegalInputError("Non-ASCII key: '%r'" % key)