We are currently indexing your data, so search results may be incomplete until we finish.
/ dulwich |
|
# _compat.py -- For dealing with python2.4 oddness
# Copyright (C) 2008 Canonical Ltd.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; version 2
# of the License or (at your option) a later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
# MA 02110-1301, USA.
"""Misc utilities to work with python <2.6.
These utilities can all be deleted when dulwich decides it wants to stop
support for python <2.6.
"""
try:
import hashlib
except ImportError:
import sha
try:
from urlparse import parse_qs
except ImportError:
from cgi import parse_qs
try:
from os import SEEK_CUR, SEEK_END
except ImportError:
SEEK_CUR = 1
SEEK_END = 2
import struct
class defaultdict(dict):
"""A python 2.4 equivalent of collections.defaultdict."""
def __init__(self, default_factory=None, *a, **kw):
if (default_factory is not None and
not hasattr(default_factory, '__call__')):
raise TypeError('first argument must be callable')
dict.__init__(self, *a, **kw)
self.default_factory = default_factory
def __getitem__(self, key):
try:
return dict.__getitem__(self, key)
except KeyError:
return self.__missing__(key)
def __missing__(self, key):
if self.default_factory is None:
raise KeyError(key)
self[key] = value = self.default_factory()
return value
def __reduce__(self):
if self.default_factory is None:
args = tuple()
else:
args = self.default_factory,
return type(self), args, None, None, self.items()
def copy(self):
return self.__copy__()
def __copy__(self):
return type(self)(self.default_factory, self)
def __deepcopy__(self, memo):
import copy
return type(self)(self.default_factory,
copy.deepcopy(self.items()))
def __repr__(self):
return 'defaultdict(%s, %s)' % (self.default_factory,
dict.__repr__(self))
def make_sha(source=''):
"""A python2.4 workaround for the sha/hashlib module fiasco."""
try:
return hashlib.sha1(source)
except NameError:
sha1 = sha.sha(source)
return sha1
def unpack_from(fmt, buf, offset=0):
"""A python2.4 workaround for struct missing unpack_from."""
try:
return struct.unpack_from(fmt, buf, offset)
except AttributeError:
b = buf[offset:offset+struct.calcsize(fmt)]
return struct.unpack(fmt, b)
try:
from itertools import permutations
except ImportError:
# Implementation of permutations from Python 2.6 documentation:
# http://docs.python.org/2.6/library/itertools.html#itertools.permutations
# Copyright (c) 2001-2010 Python Software Foundation; All Rights Reserved
# Modified syntax slightly to run under Python 2.4.
def permutations(iterable, r=None):
# permutations('ABCD', 2) --> AB AC AD BA BC BD CA CB CD DA DB DC
# permutations(range(3)) --> 012 021 102 120 201 210
pool = tuple(iterable)
n = len(pool)
if r is None:
r = n
if r > n:
return
indices = range(n)
cycles = range(n, n-r, -1)
yield tuple(pool[i] for i in indices[:r])
while n:
for i in reversed(range(r)):
cycles[i] -= 1
if cycles[i] == 0:
indices[i:] = indices[i+1:] + indices[i:i+1]
cycles[i] = n - i
else:
j = cycles[i]
indices[i], indices[-j] = indices[-j], indices[i]
yield tuple(pool[i] for i in indices[:r])
break
else:
return
try:
all = all
except NameError:
# Implementation of permutations from Python 2.6 documentation:
# http://docs.python.org/2.6/library/functions.html#all
# Copyright (c) 2001-2010 Python Software Foundation; All Rights Reserved
# Licensed under the Python Software Foundation License.
def all(iterable):
for element in iterable:
if not element:
return False
return True
try:
from collections import namedtuple
except ImportError:
# Recipe for namedtuple from http://code.activestate.com/recipes/500261/
# Copyright (c) 2007 Python Software Foundation; All Rights Reserved
# Licensed under the Python Software Foundation License.
from operator import itemgetter as _itemgetter
from keyword import iskeyword as _iskeyword
import sys as _sys
def namedtuple(typename, field_names, verbose=False, rename=False):
"""Returns a new subclass of tuple with named fields.
>>> Point = namedtuple('Point', 'x y')
>>> Point.__doc__ # docstring for the new class
'Point(x, y)'
>>> p = Point(11, y=22) # instantiate with positional args or keywords
>>> p[0] + p[1] # indexable like a plain tuple
33
>>> x, y = p # unpack like a regular tuple
>>> x, y
(11, 22)
>>> p.x + p.y # fields also accessable by name
33
>>> d = p._asdict() # convert to a dictionary
>>> d['x']
11
>>> Point(**d) # convert from a dictionary
Point(x=11, y=22)
>>> p._replace(x=100) # _replace() is like str.replace() but targets named fields
Point(x=100, y=22)
"""
# Parse and validate the field names. Validation serves two purposes,
# generating informative error messages and preventing template injection attacks.
if isinstance(field_names, basestring):
field_names = field_names.replace(',', ' ').split() # names separated by whitespace and/or commas
field_names = tuple(map(str, field_names))
if rename:
names = list(field_names)
seen = set()
for i, name in enumerate(names):
if (not min(c.isalnum() or c=='_' for c in name) or _iskeyword(name)
or not name or name[0].isdigit() or name.startswith('_')
or name in seen):
names[i] = '_%d' % i
seen.add(name)
field_names = tuple(names)
for name in (typename,) + field_names:
if not min(c.isalnum() or c=='_' for c in name):
raise ValueError('Type names and field names can only contain alphanumeric characters and underscores: %r' % name)
if _iskeyword(name):
raise ValueError('Type names and field names cannot be a keyword: %r' % name)
if name[0].isdigit():
raise ValueError('Type names and field names cannot start with a number: %r' % name)
seen_names = set()
for name in field_names:
if name.startswith('_') and not rename:
raise ValueError('Field names cannot start with an underscore: %r' % name)
if name in seen_names:
raise ValueError('Encountered duplicate field name: %r' % name)
seen_names.add(name)
# Create and fill-in the class template
numfields = len(field_names)
argtxt = repr(field_names).replace("'", "")[1:-1] # tuple repr without parens or quotes
reprtxt = ', '.join('%s=%%r' % name for name in field_names)
template = '''class %(typename)s(tuple):
'%(typename)s(%(argtxt)s)' \n
__slots__ = () \n
_fields = %(field_names)r \n
def __new__(_cls, %(argtxt)s):
return _tuple.__new__(_cls, (%(argtxt)s)) \n
@classmethod
def _make(cls, iterable, new=tuple.__new__, len=len):
'Make a new %(typename)s object from a sequence or iterable'
result = new(cls, iterable)
if len(result) != %(numfields)d:
raise TypeError('Expected %(numfields)d arguments, got %%d' %% len(result))
return result \n
def __repr__(self):
return '%(typename)s(%(reprtxt)s)' %% self \n
def _asdict(self):
'Return a new dict which maps field names to their values'
return dict(zip(self._fields, self)) \n
def _replace(_self, **kwds):
'Return a new %(typename)s object replacing specified fields with new values'
result = _self._make(map(kwds.pop, %(field_names)r, _self))
if kwds:
raise ValueError('Got unexpected field names: %%r' %% kwds.keys())
return result \n
def __getnewargs__(self):
return tuple(self) \n\n''' % locals()
for i, name in enumerate(field_names):
template += ' %s = _property(_itemgetter(%d))\n' % (name, i)
if verbose:
print template
# Execute the template string in a temporary namespace
namespace = dict(_itemgetter=_itemgetter, __name__='namedtuple_%s' % typename,
_property=property, _tuple=tuple)
try:
exec template in namespace
except SyntaxError, e:
raise SyntaxError(e.message + ':\n' + template)
result = namespace[typename]
# For pickling to work, the __module__ variable needs to be set to the frame
# where the named tuple is created. Bypass this step in enviroments where
# sys._getframe is not defined (Jython for example) or sys._getframe is not
# defined for arguments greater than 0 (IronPython).
try:
result.__module__ = _sys._getframe(1).f_globals.get('__name__', '__main__')
except (AttributeError, ValueError):
pass
return result
|
Loading...