framework/compat.py

   1 # coding=utf-8
   2 # Copyright (c) 2016 Intel Corporation
   3
   4 # Permission is hereby granted, free of charge, to any person obtaining a copy
   5 # of this software and associated documentation files (the "Software"), to deal
   6 # in the Software without restriction, including without limitation the rights
   7 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   8 # copies of the Software, and to permit persons to whom the Software is
   9 # furnished to do so, subject to the following conditions:
  10
  11 # The above copyright notice and this permission notice shall be included in
  12 # all copies or substantial portions of the Software.
  13
  14 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  17 # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  18 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  19 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  20 # SOFTWARE.
  21
  22 """A small library that contains libraries equivalent to six
  23
  24 This function is pending upstreaming in six.
  25
  26 """
  27
  28 from __future__ import (
  29     absolute_import, division, print_function, unicode_literals
  30 )
  31
  32 import six
  33
  34 def python_2_bool_compatible(class_):
  35     """A decorator to fix __bool__/__nonzero__ name changes."""
  36     if six.PY2:
  37         try:
  38             class_.__nonzero__ = class_.__bool__
  39         except AttributeError:
  40             raise ValueError(
  41                 "@python_2_bool_compatible cannot be applied to {} because "
  42                 "it doesn't define __bool__().".format(class_.__name__))
  43     return class_
  44
  45
  46 # Some version of six don't have this function
  47 try:
  48     from six import python_2_unicode_compatible
  49 except ImportError:
  50     def python_2_unicode_compatible(class_):
  51         """A decorator to fix __str/__bytes__/__unicode__ name changes."""
  52         if six.PY2:
  53             failed = False
  54             try:
  55                 class_.__unicode__ = class_.__str__
  56             except AttributeError:
  57                 failed = True
  58
  59             try:
  60                 class_.__str__ = class_.__bytes__
  61             except AttributeError:
  62                 if failed:
  63                     raise ValueError(
  64                         "@python_2_unicode_compatible cannot be applied to {} "
  65                         "because it doesn't define __str__() "
  66                         "or __bytes__().".format(class_.__name__))
  67         return class_
  68
  69
  70 try:
  71     from six import viewvalues
  72 except ImportError:
  73     if six.PY2:
  74         viewvalues = lambda d: d.viewvalues()
  75     elif six.PY3:
  76         viewvalues = lambda d: d.values()