# Copyright (C) 2010, OLPC
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the
# Free Software Foundation, Inc., 59 Temple Place - Suite 330,
# Boston, MA 02111-1307, USA.
"""
Validation and normalization of bundle versions.
Instances of :class:`NormalizedVersion` can be directly compared;
>>> from sugar.bundle.bundleversion import NormalizedVersion
>>> a = NormalizedVersion('157.3')
>>> b = NormalizedVersion('201.2')
>>> a > b
False
>>> b > a
True
Invalid versions will raise :exc:`InvalidVersionError`.
Valid versions are `1`, `1.2`, `1.2.3`, `1.2.3-peru`, and
`1.2.3~dfsg`.
Invalid versions are:
* `1.2peru` (because the suffix must be preceded with a dash or tilde),
* `1.2.` (because a version can't end with a period), or
* `1.02.5` (because a version can't have a leading zero).
Based on the implementation of :pep:`386`, but adapted to our
numeration schema.
Attributes:
VERSION_RE (RegexObject): regular expression for versions,\
deprecated, as it is insufficient by itself.
"""
import re
VERSION_RE = re.compile(
r"""
^
(?P<version>\d+) # minimum 'N'
(?P<extraversion>(?:\.\d+)*) # any number of extra '.N' segments
(?:
(?P<local>[\-\~].[a-zA-Z]*) # ignore any string in the comparison
)?
$""",
re.VERBOSE,
)
[docs]
class InvalidVersionError(Exception):
"""
A version cannot be normalized, because:
* the object is not a string,
* the string does not match the regular expression, or
* the string has a leading zero in a version part.
"""
pass
[docs]
class NormalizedVersion(object):
"""
Normalize a version string.
Args:
activity_version (str): the version string
Raises:
:exc:`InvalidVersionError`
Attributes:
parts (list): the numeric parts of the version after normalization.
"""
[docs]
def __init__(self, activity_version):
self._activity_version = activity_version
self.parts = []
self._local = None
if not isinstance(self._activity_version, str):
raise InvalidVersionError(self._activity_version)
match = VERSION_RE.search(self._activity_version)
if not match:
raise InvalidVersionError(self._activity_version)
groups = match.groupdict()
version = self._parse_version(groups["version"])
self.parts.append(version)
if groups["extraversion"] not in ("", None):
versions = self._parse_extraversions(groups["extraversion"][1:])
self.parts.extend(versions)
self._local = groups["local"]
def _parse_version(self, version_string):
"""Verify that there is no leading zero and convert to integer.
Keyword arguments:
version -- string to be parsed
Return: Version
"""
if len(version_string) > 1 and version_string[0] == "0":
raise InvalidVersionError(
"Can not have leading zero in segment"
" %s in %r" % (version_string, self._activity_version)
)
return int(version_string)
def _parse_extraversions(self, extraversion_string):
"""Split into N versions and convert them to integers, verify
that there are no leading zeros and drop trailing zeros.
Keyword arguments:
extraversion -- 'N.N.N...' sequence to be parsed
Return: List of extra versions
"""
nums = []
for n in extraversion_string.split("."):
if len(n) > 1 and n[0] == "0":
raise InvalidVersionError(
"Can not have leading zero in "
"segment %s in %r" % (n, self._activity_version)
)
nums.append(int(n))
while nums and nums[-1] == 0:
nums.pop()
return nums
def __str__(self):
version_string = ".".join(str(v) for v in self.parts)
if self._local is not None:
version_string += self._local
return version_string
def __repr__(self):
return "%s('%s')" % (self.__class__.__name__, self)
def _cannot_compare(self, other):
raise TypeError(
"Can not compare %s and %s" % (type(self).__name__, type(other).__name__)
)
def __eq__(self, other):
if not isinstance(other, NormalizedVersion):
self._cannot_compare(other)
return self.parts == other.parts
def __lt__(self, other):
if not isinstance(other, NormalizedVersion):
self._cannot_compare(other)
return self.parts < other.parts
def __ne__(self, other):
return not self.__eq__(other)
def __gt__(self, other):
return not (self.__lt__(other) or self.__eq__(other))
def __le__(self, other):
return self.__eq__(other) or self.__lt__(other)
def __ge__(self, other):
return self.__eq__(other) or self.__gt__(other)