framework/compat.py

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