212 lines
7 KiB
Python
212 lines
7 KiB
Python
#
|
|
# Copyright (c) 2001 - 2017 The SCons Foundation
|
|
#
|
|
# 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.
|
|
#
|
|
|
|
__doc__ = """
|
|
SCons compatibility package for old Python versions
|
|
|
|
This subpackage holds modules that provide backwards-compatible
|
|
implementations of various things that we'd like to use in SCons but which
|
|
only show up in later versions of Python than the early, old version(s)
|
|
we still support.
|
|
|
|
Other code will not generally reference things in this package through
|
|
the SCons.compat namespace. The modules included here add things to
|
|
the builtins namespace or the global module list so that the rest
|
|
of our code can use the objects and names imported here regardless of
|
|
Python version.
|
|
|
|
The rest of the things here will be in individual compatibility modules
|
|
that are either: 1) suitably modified copies of the future modules that
|
|
we want to use; or 2) backwards compatible re-implementations of the
|
|
specific portions of a future module's API that we want to use.
|
|
|
|
GENERAL WARNINGS: Implementations of functions in the SCons.compat
|
|
modules are *NOT* guaranteed to be fully compliant with these functions in
|
|
later versions of Python. We are only concerned with adding functionality
|
|
that we actually use in SCons, so be wary if you lift this code for
|
|
other uses. (That said, making these more nearly the same as later,
|
|
official versions is still a desirable goal, we just don't need to be
|
|
obsessive about it.)
|
|
|
|
We name the compatibility modules with an initial '_scons_' (for example,
|
|
_scons_subprocess.py is our compatibility module for subprocess) so
|
|
that we can still try to import the real module name and fall back to
|
|
our compatibility module if we get an ImportError. The import_as()
|
|
function defined below loads the module as the "real" name (without the
|
|
'_scons'), after which all of the "import {module}" statements in the
|
|
rest of our code will find our pre-loaded compatibility module.
|
|
"""
|
|
|
|
__revision__ = "src/engine/SCons/compat/__init__.py 74b2c53bc42290e911b334a6b44f187da698a668 2017/11/14 13:16:53 bdbaddog"
|
|
|
|
import os
|
|
import sys
|
|
import imp # Use the "imp" module to protect imports from fixers.
|
|
|
|
PYPY = hasattr(sys, 'pypy_translation_info')
|
|
|
|
|
|
def import_as(module, name):
|
|
"""
|
|
Imports the specified module (from our local directory) as the
|
|
specified name, returning the loaded module object.
|
|
"""
|
|
dir = os.path.split(__file__)[0]
|
|
return imp.load_module(name, *imp.find_module(module, [dir]))
|
|
|
|
|
|
def rename_module(new, old):
|
|
"""
|
|
Attempts to import the old module and load it under the new name.
|
|
Used for purely cosmetic name changes in Python 3.x.
|
|
"""
|
|
try:
|
|
sys.modules[new] = imp.load_module(old, *imp.find_module(old))
|
|
return True
|
|
except ImportError:
|
|
return False
|
|
|
|
|
|
# TODO: FIXME
|
|
# In 3.x, 'pickle' automatically loads the fast version if available.
|
|
rename_module('pickle', 'cPickle')
|
|
|
|
# Default pickle protocol. Higher protocols are more efficient/featureful
|
|
# but incompatible with older Python versions. On Python 2.7 this is 2.
|
|
# Negative numbers choose the highest available protocol.
|
|
import pickle
|
|
|
|
# Was pickle.HIGHEST_PROTOCOL
|
|
# Changed to 2 so py3.5+'s pickle will be compatible with py2.7.
|
|
PICKLE_PROTOCOL = 2
|
|
|
|
# TODO: FIXME
|
|
# In 3.x, 'profile' automatically loads the fast version if available.
|
|
rename_module('profile', 'cProfile')
|
|
|
|
# TODO: FIXME
|
|
# Before Python 3.0, the 'queue' module was named 'Queue'.
|
|
rename_module('queue', 'Queue')
|
|
|
|
# TODO: FIXME
|
|
# Before Python 3.0, the 'winreg' module was named '_winreg'
|
|
rename_module('winreg', '_winreg')
|
|
|
|
# Python 3 moved builtin intern() to sys package
|
|
# To make porting easier, make intern always live
|
|
# in sys package (for python 2.7.x)
|
|
try:
|
|
sys.intern
|
|
except AttributeError:
|
|
# We must be using python 2.7.x so monkey patch
|
|
# intern into the sys package
|
|
sys.intern = intern
|
|
|
|
# Preparing for 3.x. UserDict, UserList, UserString are in
|
|
# collections for 3.x, but standalone in 2.7.x
|
|
import collections
|
|
|
|
try:
|
|
collections.UserDict
|
|
except AttributeError:
|
|
exec ('from UserDict import UserDict as _UserDict')
|
|
collections.UserDict = _UserDict
|
|
del _UserDict
|
|
|
|
try:
|
|
collections.UserList
|
|
except AttributeError:
|
|
exec ('from UserList import UserList as _UserList')
|
|
collections.UserList = _UserList
|
|
del _UserList
|
|
|
|
try:
|
|
collections.UserString
|
|
except AttributeError:
|
|
exec ('from UserString import UserString as _UserString')
|
|
collections.UserString = _UserString
|
|
del _UserString
|
|
|
|
|
|
import shutil
|
|
try:
|
|
shutil.SameFileError
|
|
except AttributeError:
|
|
class SameFileError(Exception):
|
|
pass
|
|
|
|
shutil.SameFileError = SameFileError
|
|
|
|
def with_metaclass(meta, *bases):
|
|
"""
|
|
Function from jinja2/_compat.py. License: BSD.
|
|
|
|
Use it like this::
|
|
|
|
class BaseForm(object):
|
|
pass
|
|
|
|
class FormType(type):
|
|
pass
|
|
|
|
class Form(with_metaclass(FormType, BaseForm)):
|
|
pass
|
|
|
|
This requires a bit of explanation: the basic idea is to make a
|
|
dummy metaclass for one level of class instantiation that replaces
|
|
itself with the actual metaclass. Because of internal type checks
|
|
we also need to make sure that we downgrade the custom metaclass
|
|
for one level to something closer to type (that's why __call__ and
|
|
__init__ comes back from type etc.).
|
|
|
|
This has the advantage over six.with_metaclass of not introducing
|
|
dummy classes into the final MRO.
|
|
"""
|
|
|
|
class metaclass(meta):
|
|
__call__ = type.__call__
|
|
__init__ = type.__init__
|
|
|
|
def __new__(cls, name, this_bases, d):
|
|
if this_bases is None:
|
|
return type.__new__(cls, name, (), d)
|
|
return meta(name, bases, d)
|
|
|
|
return metaclass('temporary_class', None, {})
|
|
|
|
|
|
class NoSlotsPyPy(type):
|
|
"""
|
|
Workaround for PyPy not working well with __slots__ and __class__ assignment.
|
|
"""
|
|
|
|
def __new__(meta, name, bases, dct):
|
|
if PYPY and '__slots__' in dct:
|
|
dct.pop('__slots__')
|
|
return super(NoSlotsPyPy, meta).__new__(meta, name, bases, dct)
|
|
|
|
# Local Variables:
|
|
# tab-width:4
|
|
# indent-tabs-mode:nil
|
|
# End:
|
|
# vim: set expandtab tabstop=4 shiftwidth=4:
|