add even moar Python 3.x compatibility hacks from the six project, update license

retrying.py

@@ -1,4 +1,4 @@
-## Copyright 2013 Ray Holder
+## Copyright 2013-2014 Ray Holder
 ##
 ## Licensed under the Apache License, Version 2.0 (the "License");
 ## you may not use this file except in compliance with the License.
@@ -12,11 +12,60 @@
 ## See the License for the specific language governing permissions and
 ## limitations under the License.
 
+## --- The following is for portions of the "six" module ----------------------
+##
+## Copyright (c) 2010-2014 Benjamin Peterson
+##
+## Permission is hereby granted, free of charge, to any person obtaining a copy
+## of this software and associated documentation files (the "Software"), to deal
+## in the Software without restriction, including without limitation the rights
+## to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+## copies of the Software, and to permit persons to whom the Software is
+## furnished to do so, subject to the following conditions:
+##
+## The above copyright notice and this permission notice shall be included in all
+## copies or substantial portions of the Software.
+##
+## THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+## IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+## FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+## AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+## LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+## OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+## SOFTWARE.
+## ----------------------------------------------------------------------------
+
 import random
 import sys
 import time
 import traceback
 
+# Python 3 compatibility hacks, pilfered from https://pypi.python.org/pypi/six/1.6.1
+PY3 = sys.version_info[0] == 3
+if PY3:
+    def reraise(tp, value, tb=None):
+        if value.__traceback__ is not tb:
+            raise value.with_traceback(tb)
+        raise value
+
+else:
+    def exec_(_code_, _globs_=None, _locs_=None):
+        """Execute code in a namespace."""
+        if _globs_ is None:
+            frame = sys._getframe(1)
+            _globs_ = frame.f_globals
+            if _locs_ is None:
+                _locs_ = frame.f_locals
+            del frame
+        elif _locs_ is None:
+            _locs_ = _globs_
+        exec("""exec _code_ in _globs_, _locs_""")
+
+
+    exec_("""def reraise(tp, value, tb=None):
+    raise tp, value, tb
+""")
+
 # sys.maxint / 2, since Python 3.2 doesn't have a sys.maxint...
 MAX_WAIT = 1073741823
 
@@ -190,7 +239,7 @@ class Attempt:
             if wrap_exception:
                 raise RetryError(self)
             else:
-                raise self.value[0], self.value[1], self.value[2]
+                reraise(self.value[0], self.value[1], self.value[2])
         else:
             return self.value