hgext/lfs/pointer.py

setup: configure py2exe config via environment variables

The Inno Setup and WiX installers ship a different set of packages
with py2exe builds. And there are multiple WiX installer variants
(e.g. TortoiseHG).

Since there are multiple variants of py2exe configs and they
can be defined by entities not in our repository, let's
provide a mechanism for setup.py to supplement behavior via
environment variables. This is slighly less hacky than a setup.cfg
file IMO since the caller doesn't need to worry about mutating
global state of the source directory.

Differential Revision: https://phab.mercurial-scm.org/D6092

# pointer.py - Git-LFS pointer serialization
#
# Copyright 2017 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

import re

from mercurial.i18n import _

from mercurial import (
    error,
    pycompat,
)
from mercurial.utils import (
    stringutil,
)

class InvalidPointer(error.StorageError):
    pass

class gitlfspointer(dict):
    VERSION = 'https://git-lfs.github.com/spec/v1'

    def __init__(self, *args, **kwargs):
        self['version'] = self.VERSION
        super(gitlfspointer, self).__init__(*args)
        self.update(pycompat.byteskwargs(kwargs))

    @classmethod
    def deserialize(cls, text):
        try:
            return cls(l.split(' ', 1) for l in text.splitlines()).validate()
        except ValueError: # l.split returns 1 item instead of 2
            raise InvalidPointer(_('cannot parse git-lfs text: %s')
                                 % stringutil.pprint(text))

    def serialize(self):
        sortkeyfunc = lambda x: (x[0] != 'version', x)
        items = sorted(self.validate().iteritems(), key=sortkeyfunc)
        return ''.join('%s %s\n' % (k, v) for k, v in items)

    def oid(self):
        return self['oid'].split(':')[-1]

    def size(self):
        return int(self['size'])

    # regular expressions used by _validate
    # see https://github.com/git-lfs/git-lfs/blob/master/docs/spec.md
    _keyre = re.compile(br'\A[a-z0-9.-]+\Z')
    _valuere = re.compile(br'\A[^\n]*\Z')
    _requiredre = {
        'size': re.compile(br'\A[0-9]+\Z'),
        'oid': re.compile(br'\Asha256:[0-9a-f]{64}\Z'),
        'version': re.compile(br'\A%s\Z' % stringutil.reescape(VERSION)),
    }

    def validate(self):
        """raise InvalidPointer on error. return self if there is no error"""
        requiredcount = 0
        for k, v in self.iteritems():
            if k in self._requiredre:
                if not self._requiredre[k].match(v):
                    raise InvalidPointer(
                        _('unexpected lfs pointer value: %s=%s')
                        % (k, stringutil.pprint(v)))
                requiredcount += 1
            elif not self._keyre.match(k):
                raise InvalidPointer(_('unexpected lfs pointer key: %s') % k)
            if not self._valuere.match(v):
                raise InvalidPointer(_('unexpected lfs pointer value: %s=%s')
                                     % (k, stringutil.pprint(v)))
        if len(self._requiredre) != requiredcount:
            miss = sorted(set(self._requiredre.keys()).difference(self.keys()))
            raise InvalidPointer(_('missing lfs pointer keys: %s')
                                 % ', '.join(miss))
        return self

deserialize = gitlfspointer.deserialize