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816 lines
27 KiB
816 lines
27 KiB
"""
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Python 3 reorganized the standard library (PEP 3108). This module exposes
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several standard library modules to Python 2 under their new Python 3
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names.
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It is designed to be used as follows::
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from future import standard_library
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standard_library.install_aliases()
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And then these normal Py3 imports work on both Py3 and Py2::
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import builtins
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import copyreg
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import queue
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import reprlib
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import socketserver
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import winreg # on Windows only
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import test.support
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import html, html.parser, html.entites
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import http, http.client, http.server
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import http.cookies, http.cookiejar
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import urllib.parse, urllib.request, urllib.response, urllib.error, urllib.robotparser
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import xmlrpc.client, xmlrpc.server
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import _thread
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import _dummy_thread
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import _markupbase
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from itertools import filterfalse, zip_longest
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from sys import intern
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from collections import UserDict, UserList, UserString
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from collections import OrderedDict, Counter, ChainMap # even on Py2.6
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from subprocess import getoutput, getstatusoutput
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from subprocess import check_output # even on Py2.6
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(The renamed modules and functions are still available under their old
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names on Python 2.)
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This is a cleaner alternative to this idiom (see
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http://docs.pythonsprints.com/python3_porting/py-porting.html)::
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try:
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import queue
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except ImportError:
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import Queue as queue
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Limitations
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-----------
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We don't currently support these modules, but would like to::
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import dbm
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import dbm.dumb
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import dbm.gnu
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import collections.abc # on Py33
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import pickle # should (optionally) bring in cPickle on Python 2
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"""
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from __future__ import absolute_import, division, print_function
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import sys
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import logging
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import imp
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import contextlib
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import types
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import copy
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import os
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# Make a dedicated logger; leave the root logger to be configured
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# by the application.
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flog = logging.getLogger('future_stdlib')
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_formatter = logging.Formatter(logging.BASIC_FORMAT)
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_handler = logging.StreamHandler()
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_handler.setFormatter(_formatter)
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flog.addHandler(_handler)
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flog.setLevel(logging.WARN)
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from future.utils import PY2, PY3
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# The modules that are defined under the same names on Py3 but with
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# different contents in a significant way (e.g. submodules) are:
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# pickle (fast one)
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# dbm
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# urllib
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# test
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# email
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REPLACED_MODULES = set(['test', 'urllib', 'pickle', 'dbm']) # add email and dbm when we support it
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# The following module names are not present in Python 2.x, so they cause no
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# potential clashes between the old and new names:
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# http
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# html
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# tkinter
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# xmlrpc
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# Keys: Py2 / real module names
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# Values: Py3 / simulated module names
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RENAMES = {
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# 'cStringIO': 'io', # there's a new io module in Python 2.6
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# that provides StringIO and BytesIO
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# 'StringIO': 'io', # ditto
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# 'cPickle': 'pickle',
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'__builtin__': 'builtins',
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'copy_reg': 'copyreg',
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'Queue': 'queue',
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'future.moves.socketserver': 'socketserver',
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'ConfigParser': 'configparser',
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'repr': 'reprlib',
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# 'FileDialog': 'tkinter.filedialog',
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# 'tkFileDialog': 'tkinter.filedialog',
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# 'SimpleDialog': 'tkinter.simpledialog',
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# 'tkSimpleDialog': 'tkinter.simpledialog',
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# 'tkColorChooser': 'tkinter.colorchooser',
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# 'tkCommonDialog': 'tkinter.commondialog',
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# 'Dialog': 'tkinter.dialog',
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# 'Tkdnd': 'tkinter.dnd',
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# 'tkFont': 'tkinter.font',
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# 'tkMessageBox': 'tkinter.messagebox',
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# 'ScrolledText': 'tkinter.scrolledtext',
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# 'Tkconstants': 'tkinter.constants',
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# 'Tix': 'tkinter.tix',
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# 'ttk': 'tkinter.ttk',
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# 'Tkinter': 'tkinter',
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'_winreg': 'winreg',
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'thread': '_thread',
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'dummy_thread': '_dummy_thread',
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# 'anydbm': 'dbm', # causes infinite import loop
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# 'whichdb': 'dbm', # causes infinite import loop
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# anydbm and whichdb are handled by fix_imports2
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# 'dbhash': 'dbm.bsd',
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# 'dumbdbm': 'dbm.dumb',
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# 'dbm': 'dbm.ndbm',
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# 'gdbm': 'dbm.gnu',
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'future.moves.xmlrpc': 'xmlrpc',
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# 'future.backports.email': 'email', # for use by urllib
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# 'DocXMLRPCServer': 'xmlrpc.server',
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# 'SimpleXMLRPCServer': 'xmlrpc.server',
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# 'httplib': 'http.client',
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# 'htmlentitydefs' : 'html.entities',
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# 'HTMLParser' : 'html.parser',
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# 'Cookie': 'http.cookies',
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# 'cookielib': 'http.cookiejar',
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# 'BaseHTTPServer': 'http.server',
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# 'SimpleHTTPServer': 'http.server',
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# 'CGIHTTPServer': 'http.server',
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# 'future.backports.test': 'test', # primarily for renaming test_support to support
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# 'commands': 'subprocess',
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# 'urlparse' : 'urllib.parse',
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# 'robotparser' : 'urllib.robotparser',
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# 'abc': 'collections.abc', # for Py33
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# 'future.utils.six.moves.html': 'html',
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# 'future.utils.six.moves.http': 'http',
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'future.moves.html': 'html',
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'future.moves.http': 'http',
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# 'future.backports.urllib': 'urllib',
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# 'future.utils.six.moves.urllib': 'urllib',
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'future.moves._markupbase': '_markupbase',
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}
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# It is complicated and apparently brittle to mess around with the
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# ``sys.modules`` cache in order to support "import urllib" meaning two
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# different things (Py2.7 urllib and backported Py3.3-like urllib) in different
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# contexts. So we require explicit imports for these modules.
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assert len(set(RENAMES.values()) & set(REPLACED_MODULES)) == 0
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# Harmless renames that we can insert.
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# These modules need names from elsewhere being added to them:
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# subprocess: should provide getoutput and other fns from commands
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# module but these fns are missing: getstatus, mk2arg,
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# mkarg
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# re: needs an ASCII constant that works compatibly with Py3
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# etc: see lib2to3/fixes/fix_imports.py
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# (New module name, new object name, old module name, old object name)
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MOVES = [('collections', 'UserList', 'UserList', 'UserList'),
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('collections', 'UserDict', 'UserDict', 'UserDict'),
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('collections', 'UserString','UserString', 'UserString'),
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('collections', 'ChainMap', 'future.backports.misc', 'ChainMap'),
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('itertools', 'filterfalse','itertools', 'ifilterfalse'),
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('itertools', 'zip_longest','itertools', 'izip_longest'),
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('sys', 'intern','__builtin__', 'intern'),
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# The re module has no ASCII flag in Py2, but this is the default.
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# Set re.ASCII to a zero constant. stat.ST_MODE just happens to be one
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# (and it exists on Py2.6+).
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('re', 'ASCII','stat', 'ST_MODE'),
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('base64', 'encodebytes','base64', 'encodestring'),
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('base64', 'decodebytes','base64', 'decodestring'),
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('subprocess', 'getoutput', 'commands', 'getoutput'),
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('subprocess', 'getstatusoutput', 'commands', 'getstatusoutput'),
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('subprocess', 'check_output', 'future.backports.misc', 'check_output'),
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('math', 'ceil', 'future.backports.misc', 'ceil'),
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('collections', 'OrderedDict', 'future.backports.misc', 'OrderedDict'),
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('collections', 'Counter', 'future.backports.misc', 'Counter'),
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('collections', 'ChainMap', 'future.backports.misc', 'ChainMap'),
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('itertools', 'count', 'future.backports.misc', 'count'),
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('reprlib', 'recursive_repr', 'future.backports.misc', 'recursive_repr'),
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('functools', 'cmp_to_key', 'future.backports.misc', 'cmp_to_key'),
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# This is no use, since "import urllib.request" etc. still fails:
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# ('urllib', 'error', 'future.moves.urllib', 'error'),
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# ('urllib', 'parse', 'future.moves.urllib', 'parse'),
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# ('urllib', 'request', 'future.moves.urllib', 'request'),
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# ('urllib', 'response', 'future.moves.urllib', 'response'),
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# ('urllib', 'robotparser', 'future.moves.urllib', 'robotparser'),
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]
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# A minimal example of an import hook:
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# class WarnOnImport(object):
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# def __init__(self, *args):
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# self.module_names = args
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#
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# def find_module(self, fullname, path=None):
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# if fullname in self.module_names:
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# self.path = path
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# return self
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# return None
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#
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# def load_module(self, name):
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# if name in sys.modules:
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# return sys.modules[name]
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# module_info = imp.find_module(name, self.path)
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# module = imp.load_module(name, *module_info)
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# sys.modules[name] = module
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# flog.warning("Imported deprecated module %s", name)
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# return module
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class RenameImport(object):
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"""
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A class for import hooks mapping Py3 module names etc. to the Py2 equivalents.
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"""
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# Different RenameImport classes are created when importing this module from
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# different source files. This causes isinstance(hook, RenameImport) checks
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# to produce inconsistent results. We add this RENAMER attribute here so
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# remove_hooks() and install_hooks() can find instances of these classes
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# easily:
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RENAMER = True
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def __init__(self, old_to_new):
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'''
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Pass in a dictionary-like object mapping from old names to new
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names. E.g. {'ConfigParser': 'configparser', 'cPickle': 'pickle'}
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'''
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self.old_to_new = old_to_new
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both = set(old_to_new.keys()) & set(old_to_new.values())
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assert (len(both) == 0 and
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len(set(old_to_new.values())) == len(old_to_new.values())), \
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'Ambiguity in renaming (handler not implemented)'
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self.new_to_old = dict((new, old) for (old, new) in old_to_new.items())
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def find_module(self, fullname, path=None):
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# Handles hierarchical importing: package.module.module2
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new_base_names = set([s.split('.')[0] for s in self.new_to_old])
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# Before v0.12: Was: if fullname in set(self.old_to_new) | new_base_names:
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if fullname in new_base_names:
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return self
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return None
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def load_module(self, name):
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path = None
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if name in sys.modules:
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return sys.modules[name]
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elif name in self.new_to_old:
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# New name. Look up the corresponding old (Py2) name:
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oldname = self.new_to_old[name]
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module = self._find_and_load_module(oldname)
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# module.__future_module__ = True
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else:
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module = self._find_and_load_module(name)
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# In any case, make it available under the requested (Py3) name
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sys.modules[name] = module
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return module
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def _find_and_load_module(self, name, path=None):
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"""
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Finds and loads it. But if there's a . in the name, handles it
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properly.
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"""
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bits = name.split('.')
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while len(bits) > 1:
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# Treat the first bit as a package
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packagename = bits.pop(0)
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package = self._find_and_load_module(packagename, path)
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try:
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path = package.__path__
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except AttributeError:
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# This could be e.g. moves.
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flog.debug('Package {0} has no __path__.'.format(package))
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if name in sys.modules:
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return sys.modules[name]
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flog.debug('What to do here?')
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name = bits[0]
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module_info = imp.find_module(name, path)
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return imp.load_module(name, *module_info)
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class hooks(object):
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"""
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Acts as a context manager. Saves the state of sys.modules and restores it
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after the 'with' block.
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Use like this:
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>>> from future import standard_library
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>>> with standard_library.hooks():
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... import http.client
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>>> import requests
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For this to work, http.client will be scrubbed from sys.modules after the
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'with' block. That way the modules imported in the 'with' block will
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continue to be accessible in the current namespace but not from any
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imported modules (like requests).
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"""
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def __enter__(self):
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# flog.debug('Entering hooks context manager')
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self.old_sys_modules = copy.copy(sys.modules)
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self.hooks_were_installed = detect_hooks()
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# self.scrubbed = scrub_py2_sys_modules()
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install_hooks()
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return self
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def __exit__(self, *args):
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# flog.debug('Exiting hooks context manager')
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# restore_sys_modules(self.scrubbed)
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if not self.hooks_were_installed:
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remove_hooks()
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# scrub_future_sys_modules()
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# Sanity check for is_py2_stdlib_module(): We aren't replacing any
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# builtin modules names:
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if PY2:
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assert len(set(RENAMES.values()) & set(sys.builtin_module_names)) == 0
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def is_py2_stdlib_module(m):
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"""
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Tries to infer whether the module m is from the Python 2 standard library.
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This may not be reliable on all systems.
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"""
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if PY3:
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return False
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if not 'stdlib_path' in is_py2_stdlib_module.__dict__:
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stdlib_files = [contextlib.__file__, os.__file__, copy.__file__]
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stdlib_paths = [os.path.split(f)[0] for f in stdlib_files]
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if not len(set(stdlib_paths)) == 1:
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# This seems to happen on travis-ci.org. Very strange. We'll try to
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# ignore it.
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flog.warn('Multiple locations found for the Python standard '
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'library: %s' % stdlib_paths)
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# Choose the first one arbitrarily
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is_py2_stdlib_module.stdlib_path = stdlib_paths[0]
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if m.__name__ in sys.builtin_module_names:
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return True
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if hasattr(m, '__file__'):
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modpath = os.path.split(m.__file__)
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if (modpath[0].startswith(is_py2_stdlib_module.stdlib_path) and
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'site-packages' not in modpath[0]):
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return True
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return False
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def scrub_py2_sys_modules():
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"""
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Removes any Python 2 standard library modules from ``sys.modules`` that
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would interfere with Py3-style imports using import hooks. Examples are
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modules with the same names (like urllib or email).
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(Note that currently import hooks are disabled for modules like these
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with ambiguous names anyway ...)
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"""
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if PY3:
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return {}
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scrubbed = {}
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for modulename in REPLACED_MODULES & set(RENAMES.keys()):
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if not modulename in sys.modules:
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continue
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module = sys.modules[modulename]
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if is_py2_stdlib_module(module):
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flog.debug('Deleting (Py2) {} from sys.modules'.format(modulename))
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scrubbed[modulename] = sys.modules[modulename]
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del sys.modules[modulename]
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return scrubbed
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def scrub_future_sys_modules():
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"""
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Deprecated.
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"""
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return {}
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class suspend_hooks(object):
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"""
|
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Acts as a context manager. Use like this:
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>>> from future import standard_library
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>>> standard_library.install_hooks()
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>>> import http.client
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>>> # ...
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>>> with standard_library.suspend_hooks():
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>>> import requests # incompatible with ``future``'s standard library hooks
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If the hooks were disabled before the context, they are not installed when
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the context is left.
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"""
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def __enter__(self):
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self.hooks_were_installed = detect_hooks()
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remove_hooks()
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# self.scrubbed = scrub_future_sys_modules()
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return self
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def __exit__(self, *args):
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if self.hooks_were_installed:
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install_hooks()
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# restore_sys_modules(self.scrubbed)
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|
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def restore_sys_modules(scrubbed):
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"""
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|
Add any previously scrubbed modules back to the sys.modules cache,
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but only if it's safe to do so.
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"""
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clash = set(sys.modules) & set(scrubbed)
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if len(clash) != 0:
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# If several, choose one arbitrarily to raise an exception about
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|
first = list(clash)[0]
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raise ImportError('future module {} clashes with Py2 module'
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.format(first))
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sys.modules.update(scrubbed)
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|
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|
def install_aliases():
|
|
"""
|
|
Monkey-patches the standard library in Py2.6/7 to provide
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|
aliases for better Py3 compatibility.
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|
"""
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|
if PY3:
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|
return
|
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# if hasattr(install_aliases, 'run_already'):
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|
# return
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|
for (newmodname, newobjname, oldmodname, oldobjname) in MOVES:
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__import__(newmodname)
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|
# We look up the module in sys.modules because __import__ just returns the
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# top-level package:
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|
newmod = sys.modules[newmodname]
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|
# newmod.__future_module__ = True
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__import__(oldmodname)
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oldmod = sys.modules[oldmodname]
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obj = getattr(oldmod, oldobjname)
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setattr(newmod, newobjname, obj)
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|
|
# Hack for urllib so it appears to have the same structure on Py2 as on Py3
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|
import urllib
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|
from future.backports.urllib import request
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from future.backports.urllib import response
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|
from future.backports.urllib import parse
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|
from future.backports.urllib import error
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|
from future.backports.urllib import robotparser
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urllib.request = request
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urllib.response = response
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urllib.parse = parse
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|
urllib.error = error
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urllib.robotparser = robotparser
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sys.modules['urllib.request'] = request
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sys.modules['urllib.response'] = response
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sys.modules['urllib.parse'] = parse
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|
sys.modules['urllib.error'] = error
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sys.modules['urllib.robotparser'] = robotparser
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|
|
|
# Patch the test module so it appears to have the same structure on Py2 as on Py3
|
|
try:
|
|
import test
|
|
except ImportError:
|
|
pass
|
|
try:
|
|
from future.moves.test import support
|
|
except ImportError:
|
|
pass
|
|
else:
|
|
test.support = support
|
|
sys.modules['test.support'] = support
|
|
|
|
# Patch the dbm module so it appears to have the same structure on Py2 as on Py3
|
|
try:
|
|
import dbm
|
|
except ImportError:
|
|
pass
|
|
else:
|
|
from future.moves.dbm import dumb
|
|
dbm.dumb = dumb
|
|
sys.modules['dbm.dumb'] = dumb
|
|
try:
|
|
from future.moves.dbm import gnu
|
|
except ImportError:
|
|
pass
|
|
else:
|
|
dbm.gnu = gnu
|
|
sys.modules['dbm.gnu'] = gnu
|
|
try:
|
|
from future.moves.dbm import ndbm
|
|
except ImportError:
|
|
pass
|
|
else:
|
|
dbm.ndbm = ndbm
|
|
sys.modules['dbm.ndbm'] = ndbm
|
|
|
|
# install_aliases.run_already = True
|
|
|
|
|
|
def install_hooks():
|
|
"""
|
|
This function installs the future.standard_library import hook into
|
|
sys.meta_path.
|
|
"""
|
|
if PY3:
|
|
return
|
|
|
|
install_aliases()
|
|
|
|
flog.debug('sys.meta_path was: {0}'.format(sys.meta_path))
|
|
flog.debug('Installing hooks ...')
|
|
|
|
# Add it unless it's there already
|
|
newhook = RenameImport(RENAMES)
|
|
if not detect_hooks():
|
|
sys.meta_path.append(newhook)
|
|
flog.debug('sys.meta_path is now: {0}'.format(sys.meta_path))
|
|
|
|
|
|
def enable_hooks():
|
|
"""
|
|
Deprecated. Use install_hooks() instead. This will be removed by
|
|
``future`` v1.0.
|
|
"""
|
|
install_hooks()
|
|
|
|
|
|
def remove_hooks(scrub_sys_modules=False):
|
|
"""
|
|
This function removes the import hook from sys.meta_path.
|
|
"""
|
|
if PY3:
|
|
return
|
|
flog.debug('Uninstalling hooks ...')
|
|
# Loop backwards, so deleting items keeps the ordering:
|
|
for i, hook in list(enumerate(sys.meta_path))[::-1]:
|
|
if hasattr(hook, 'RENAMER'):
|
|
del sys.meta_path[i]
|
|
|
|
# Explicit is better than implicit. In the future the interface should
|
|
# probably change so that scrubbing the import hooks requires a separate
|
|
# function call. Left as is for now for backward compatibility with
|
|
# v0.11.x.
|
|
if scrub_sys_modules:
|
|
scrub_future_sys_modules()
|
|
|
|
|
|
def disable_hooks():
|
|
"""
|
|
Deprecated. Use remove_hooks() instead. This will be removed by
|
|
``future`` v1.0.
|
|
"""
|
|
remove_hooks()
|
|
|
|
|
|
def detect_hooks():
|
|
"""
|
|
Returns True if the import hooks are installed, False if not.
|
|
"""
|
|
flog.debug('Detecting hooks ...')
|
|
present = any([hasattr(hook, 'RENAMER') for hook in sys.meta_path])
|
|
if present:
|
|
flog.debug('Detected.')
|
|
else:
|
|
flog.debug('Not detected.')
|
|
return present
|
|
|
|
|
|
# As of v0.12, this no longer happens implicitly:
|
|
# if not PY3:
|
|
# install_hooks()
|
|
|
|
|
|
if not hasattr(sys, 'py2_modules'):
|
|
sys.py2_modules = {}
|
|
|
|
def cache_py2_modules():
|
|
"""
|
|
Currently this function is unneeded, as we are not attempting to provide import hooks
|
|
for modules with ambiguous names: email, urllib, pickle.
|
|
"""
|
|
if len(sys.py2_modules) != 0:
|
|
return
|
|
assert not detect_hooks()
|
|
import urllib
|
|
sys.py2_modules['urllib'] = urllib
|
|
|
|
import email
|
|
sys.py2_modules['email'] = email
|
|
|
|
import pickle
|
|
sys.py2_modules['pickle'] = pickle
|
|
|
|
# Not all Python installations have test module. (Anaconda doesn't, for example.)
|
|
# try:
|
|
# import test
|
|
# except ImportError:
|
|
# sys.py2_modules['test'] = None
|
|
# sys.py2_modules['test'] = test
|
|
|
|
# import dbm
|
|
# sys.py2_modules['dbm'] = dbm
|
|
|
|
|
|
def import_(module_name, backport=False):
|
|
"""
|
|
Pass a (potentially dotted) module name of a Python 3 standard library
|
|
module. This function imports the module compatibly on Py2 and Py3 and
|
|
returns the top-level module.
|
|
|
|
Example use:
|
|
>>> http = import_('http.client')
|
|
>>> http = import_('http.server')
|
|
>>> urllib = import_('urllib.request')
|
|
|
|
Then:
|
|
>>> conn = http.client.HTTPConnection(...)
|
|
>>> response = urllib.request.urlopen('http://mywebsite.com')
|
|
>>> # etc.
|
|
|
|
Use as follows:
|
|
>>> package_name = import_(module_name)
|
|
|
|
On Py3, equivalent to this:
|
|
|
|
>>> import module_name
|
|
|
|
On Py2, equivalent to this if backport=False:
|
|
|
|
>>> from future.moves import module_name
|
|
|
|
or to this if backport=True:
|
|
|
|
>>> from future.backports import module_name
|
|
|
|
except that it also handles dotted module names such as ``http.client``
|
|
The effect then is like this:
|
|
|
|
>>> from future.backports import module
|
|
>>> from future.backports.module import submodule
|
|
>>> module.submodule = submodule
|
|
|
|
Note that this would be a SyntaxError in Python:
|
|
|
|
>>> from future.backports import http.client
|
|
|
|
"""
|
|
# Python 2.6 doesn't have importlib in the stdlib, so it requires
|
|
# the backported ``importlib`` package from PyPI as a dependency to use
|
|
# this function:
|
|
import importlib
|
|
|
|
if PY3:
|
|
return __import__(module_name)
|
|
else:
|
|
# client.blah = blah
|
|
# Then http.client = client
|
|
# etc.
|
|
if backport:
|
|
prefix = 'future.backports'
|
|
else:
|
|
prefix = 'future.moves'
|
|
parts = prefix.split('.') + module_name.split('.')
|
|
|
|
modules = []
|
|
for i, part in enumerate(parts):
|
|
sofar = '.'.join(parts[:i+1])
|
|
modules.append(importlib.import_module(sofar))
|
|
for i, part in reversed(list(enumerate(parts))):
|
|
if i == 0:
|
|
break
|
|
setattr(modules[i-1], part, modules[i])
|
|
|
|
# Return the next-most top-level module after future.backports / future.moves:
|
|
return modules[2]
|
|
|
|
|
|
def from_import(module_name, *symbol_names, **kwargs):
|
|
"""
|
|
Example use:
|
|
>>> HTTPConnection = from_import('http.client', 'HTTPConnection')
|
|
>>> HTTPServer = from_import('http.server', 'HTTPServer')
|
|
>>> urlopen, urlparse = from_import('urllib.request', 'urlopen', 'urlparse')
|
|
|
|
Equivalent to this on Py3:
|
|
|
|
>>> from module_name import symbol_names[0], symbol_names[1], ...
|
|
|
|
and this on Py2:
|
|
|
|
>>> from future.moves.module_name import symbol_names[0], ...
|
|
|
|
or:
|
|
|
|
>>> from future.backports.module_name import symbol_names[0], ...
|
|
|
|
except that it also handles dotted module names such as ``http.client``.
|
|
"""
|
|
|
|
if PY3:
|
|
return __import__(module_name)
|
|
else:
|
|
if 'backport' in kwargs and bool(kwargs['backport']):
|
|
prefix = 'future.backports'
|
|
else:
|
|
prefix = 'future.moves'
|
|
parts = prefix.split('.') + module_name.split('.')
|
|
module = importlib.import_module(prefix + '.' + module_name)
|
|
output = [getattr(module, name) for name in symbol_names]
|
|
if len(output) == 1:
|
|
return output[0]
|
|
else:
|
|
return output
|
|
|
|
|
|
class exclude_local_folder_imports(object):
|
|
"""
|
|
A context-manager that prevents standard library modules like configparser
|
|
from being imported from the local python-future source folder on Py3.
|
|
|
|
(This was need prior to v0.16.0 because the presence of a configparser
|
|
folder would otherwise have prevented setuptools from running on Py3. Maybe
|
|
it's not needed any more?)
|
|
"""
|
|
def __init__(self, *args):
|
|
assert len(args) > 0
|
|
self.module_names = args
|
|
# Disallow dotted module names like http.client:
|
|
if any(['.' in m for m in self.module_names]):
|
|
raise NotImplementedError('Dotted module names are not supported')
|
|
|
|
def __enter__(self):
|
|
self.old_sys_path = copy.copy(sys.path)
|
|
self.old_sys_modules = copy.copy(sys.modules)
|
|
if sys.version_info[0] < 3:
|
|
return
|
|
# The presence of all these indicates we've found our source folder,
|
|
# because `builtins` won't have been installed in site-packages by setup.py:
|
|
FUTURE_SOURCE_SUBFOLDERS = ['future', 'past', 'libfuturize', 'libpasteurize', 'builtins']
|
|
|
|
# Look for the future source folder:
|
|
for folder in self.old_sys_path:
|
|
if all([os.path.exists(os.path.join(folder, subfolder))
|
|
for subfolder in FUTURE_SOURCE_SUBFOLDERS]):
|
|
# Found it. Remove it.
|
|
sys.path.remove(folder)
|
|
|
|
# Ensure we import the system module:
|
|
for m in self.module_names:
|
|
# Delete the module and any submodules from sys.modules:
|
|
# for key in list(sys.modules):
|
|
# if key == m or key.startswith(m + '.'):
|
|
# try:
|
|
# del sys.modules[key]
|
|
# except KeyError:
|
|
# pass
|
|
try:
|
|
module = __import__(m, level=0)
|
|
except ImportError:
|
|
# There's a problem importing the system module. E.g. the
|
|
# winreg module is not available except on Windows.
|
|
pass
|
|
|
|
def __exit__(self, *args):
|
|
# Restore sys.path and sys.modules:
|
|
sys.path = self.old_sys_path
|
|
for m in set(self.old_sys_modules.keys()) - set(sys.modules.keys()):
|
|
sys.modules[m] = self.old_sys_modules[m]
|
|
|
|
TOP_LEVEL_MODULES = ['builtins',
|
|
'copyreg',
|
|
'html',
|
|
'http',
|
|
'queue',
|
|
'reprlib',
|
|
'socketserver',
|
|
'test',
|
|
'tkinter',
|
|
'winreg',
|
|
'xmlrpc',
|
|
'_dummy_thread',
|
|
'_markupbase',
|
|
'_thread',
|
|
]
|
|
|
|
def import_top_level_modules():
|
|
with exclude_local_folder_imports(*TOP_LEVEL_MODULES):
|
|
for m in TOP_LEVEL_MODULES:
|
|
try:
|
|
__import__(m)
|
|
except ImportError: # e.g. winreg
|
|
pass
|