# encoding: utf-8

# The MIT License

#

# Copyright (c) 2012 the bpython authors.

# Copyright (c) 2015 Sebastian Ramacher

#

# 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.

"""

Helper module for Python 3 compatibility.

Defines the following attributes:

- PythonLexer: Pygment's Python lexer matching the hosting runtime's

Python version.

- py3: True if the hosting Python runtime is of Python version 3 or later

"""

import sys

py3 = (sys.version_info[0] == 3)

if py3:

from pygments.lexers import Python3Lexer as PythonLexer

else:

from pygments.lexers import PythonLexer

if py3 or sys.version_info[:3] >= (2, 7, 3):

def prepare_for_exec(arg, encoding=None):

return arg

else:

def prepare_for_exec(arg, encoding=None):

return arg.encode(encoding)

def try_decode(s, encoding):

"""Try to decode s which is str names. Return None if not decodable"""

if not py3 and not isinstance(s, unicode):

try:

return s.decode(encoding)

except UnicodeDecodeError:

return None

return s