templates: add filter to reverse list
The filter supports only lists because for lists, it’s straightforward to
implement. Reversing text doesn’t seem very useful and is hard to implement.
Reversing the bytes would break multi-bytes encodings. Reversing the code
points would break characters consisting of multiple code points. Reversing
graphemes is non-trivial without using a library not included in the standard
library.
# 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.
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 = b'https://git-lfs.github.com/spec/v1'
def __init__(self, *args, **kwargs):
self[b'version'] = self.VERSION
super(gitlfspointer, self).__init__(*args)
self.update(pycompat.byteskwargs(kwargs))
@classmethod
def deserialize(cls, text):
try:
return cls(l.split(b' ', 1) for l in text.splitlines()).validate()
except ValueError: # l.split returns 1 item instead of 2
raise InvalidPointer(
_(b'cannot parse git-lfs text: %s') % stringutil.pprint(text)
)
def serialize(self):
sortkeyfunc = lambda x: (x[0] != b'version', x)
items = sorted(self.validate().items(), key=sortkeyfunc)
return b''.join(b'%s %s\n' % (k, v) for k, v in items)
def oid(self):
return self[b'oid'].split(b':')[-1]
def size(self):
return int(self[b'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 = {
b'size': re.compile(br'\A[0-9]+\Z'),
b'oid': re.compile(br'\Asha256:[0-9a-f]{64}\Z'),
b'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.items():
if k in self._requiredre:
if not self._requiredre[k].match(v):
raise InvalidPointer(
_(b'unexpected lfs pointer value: %s=%s')
% (k, stringutil.pprint(v))
)
requiredcount += 1
elif not self._keyre.match(k):
raise InvalidPointer(_(b'unexpected lfs pointer key: %s') % k)
if not self._valuere.match(v):
raise InvalidPointer(
_(b'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(
_(b'missing lfs pointer keys: %s') % b', '.join(miss)
)
return self
deserialize = gitlfspointer.deserialize