bazarr/libs/git/objects/util.py

364 lines
12 KiB
Python
Raw Normal View History

# util.py
# Copyright (C) 2008, 2009 Michael Trier (mtrier@gmail.com) and contributors
#
# This module is part of GitPython and is released under
# the BSD License: http://www.opensource.org/licenses/bsd-license.php
"""Module for general utility functions"""
from git.util import (
IterableList,
Actor
)
import re
from collections import deque as Deque
from string import digits
import time
import calendar
from datetime import datetime, timedelta, tzinfo
__all__ = ('get_object_type_by_name', 'parse_date', 'parse_actor_and_date',
'ProcessStreamAdapter', 'Traversable', 'altz_to_utctz_str', 'utctz_to_altz',
'verify_utctz', 'Actor', 'tzoffset', 'utc')
ZERO = timedelta(0)
#{ Functions
def mode_str_to_int(modestr):
"""
:param modestr: string like 755 or 644 or 100644 - only the last 6 chars will be used
:return:
String identifying a mode compatible to the mode methods ids of the
stat module regarding the rwx permissions for user, group and other,
special flags and file system flags, i.e. whether it is a symlink
for example."""
mode = 0
for iteration, char in enumerate(reversed(modestr[-6:])):
mode += int(char) << iteration * 3
# END for each char
return mode
def get_object_type_by_name(object_type_name):
"""
:return: type suitable to handle the given object type name.
Use the type to create new instances.
:param object_type_name: Member of TYPES
:raise ValueError: In case object_type_name is unknown"""
if object_type_name == b"commit":
from . import commit
return commit.Commit
elif object_type_name == b"tag":
from . import tag
return tag.TagObject
elif object_type_name == b"blob":
from . import blob
return blob.Blob
elif object_type_name == b"tree":
from . import tree
return tree.Tree
else:
raise ValueError("Cannot handle unknown object type: %s" % object_type_name)
def utctz_to_altz(utctz):
"""we convert utctz to the timezone in seconds, it is the format time.altzone
returns. Git stores it as UTC timezone which has the opposite sign as well,
which explains the -1 * ( that was made explicit here )
:param utctz: git utc timezone string, i.e. +0200"""
return -1 * int(float(utctz) / 100 * 3600)
def altz_to_utctz_str(altz):
"""As above, but inverses the operation, returning a string that can be used
in commit objects"""
utci = -1 * int((float(altz) / 3600) * 100)
utcs = str(abs(utci))
utcs = "0" * (4 - len(utcs)) + utcs
prefix = (utci < 0 and '-') or '+'
return prefix + utcs
def verify_utctz(offset):
""":raise ValueError: if offset is incorrect
:return: offset"""
fmt_exc = ValueError("Invalid timezone offset format: %s" % offset)
if len(offset) != 5:
raise fmt_exc
if offset[0] not in "+-":
raise fmt_exc
if offset[1] not in digits or\
offset[2] not in digits or\
offset[3] not in digits or\
offset[4] not in digits:
raise fmt_exc
# END for each char
return offset
class tzoffset(tzinfo):
def __init__(self, secs_west_of_utc, name=None):
self._offset = timedelta(seconds=-secs_west_of_utc)
self._name = name or 'fixed'
def utcoffset(self, dt):
return self._offset
def tzname(self, dt):
return self._name
def dst(self, dt):
return ZERO
utc = tzoffset(0, 'UTC')
def from_timestamp(timestamp, tz_offset):
"""Converts a timestamp + tz_offset into an aware datetime instance."""
utc_dt = datetime.fromtimestamp(timestamp, utc)
try:
local_dt = utc_dt.astimezone(tzoffset(tz_offset))
return local_dt
except ValueError:
return utc_dt
def parse_date(string_date):
"""
Parse the given date as one of the following
* Git internal format: timestamp offset
* RFC 2822: Thu, 07 Apr 2005 22:13:13 +0200.
* ISO 8601 2005-04-07T22:13:13
The T can be a space as well
:return: Tuple(int(timestamp_UTC), int(offset)), both in seconds since epoch
:raise ValueError: If the format could not be understood
:note: Date can also be YYYY.MM.DD, MM/DD/YYYY and DD.MM.YYYY.
"""
# git time
try:
if string_date.count(' ') == 1 and string_date.rfind(':') == -1:
timestamp, offset = string_date.split()
timestamp = int(timestamp)
return timestamp, utctz_to_altz(verify_utctz(offset))
else:
offset = "+0000" # local time by default
if string_date[-5] in '-+':
offset = verify_utctz(string_date[-5:])
string_date = string_date[:-6] # skip space as well
# END split timezone info
offset = utctz_to_altz(offset)
# now figure out the date and time portion - split time
date_formats = []
splitter = -1
if ',' in string_date:
date_formats.append("%a, %d %b %Y")
splitter = string_date.rfind(' ')
else:
# iso plus additional
date_formats.append("%Y-%m-%d")
date_formats.append("%Y.%m.%d")
date_formats.append("%m/%d/%Y")
date_formats.append("%d.%m.%Y")
splitter = string_date.rfind('T')
if splitter == -1:
splitter = string_date.rfind(' ')
# END handle 'T' and ' '
# END handle rfc or iso
assert splitter > -1
# split date and time
time_part = string_date[splitter + 1:] # skip space
date_part = string_date[:splitter]
# parse time
tstruct = time.strptime(time_part, "%H:%M:%S")
for fmt in date_formats:
try:
dtstruct = time.strptime(date_part, fmt)
utctime = calendar.timegm((dtstruct.tm_year, dtstruct.tm_mon, dtstruct.tm_mday,
tstruct.tm_hour, tstruct.tm_min, tstruct.tm_sec,
dtstruct.tm_wday, dtstruct.tm_yday, tstruct.tm_isdst))
return int(utctime), offset
except ValueError:
continue
# END exception handling
# END for each fmt
# still here ? fail
raise ValueError("no format matched")
# END handle format
except Exception:
raise ValueError("Unsupported date format: %s" % string_date)
# END handle exceptions
# precompiled regex
_re_actor_epoch = re.compile(r'^.+? (.*) (\d+) ([+-]\d+).*$')
_re_only_actor = re.compile(r'^.+? (.*)$')
def parse_actor_and_date(line):
"""Parse out the actor (author or committer) info from a line like::
author Tom Preston-Werner <tom@mojombo.com> 1191999972 -0700
:return: [Actor, int_seconds_since_epoch, int_timezone_offset]"""
actor, epoch, offset = '', 0, 0
m = _re_actor_epoch.search(line)
if m:
actor, epoch, offset = m.groups()
else:
m = _re_only_actor.search(line)
actor = m.group(1) if m else line or ''
return (Actor._from_string(actor), int(epoch), utctz_to_altz(offset))
#} END functions
#{ Classes
class ProcessStreamAdapter(object):
"""Class wireing all calls to the contained Process instance.
Use this type to hide the underlying process to provide access only to a specified
stream. The process is usually wrapped into an AutoInterrupt class to kill
it if the instance goes out of scope."""
__slots__ = ("_proc", "_stream")
def __init__(self, process, stream_name):
self._proc = process
self._stream = getattr(process, stream_name)
def __getattr__(self, attr):
return getattr(self._stream, attr)
class Traversable(object):
"""Simple interface to perform depth-first or breadth-first traversals
into one direction.
Subclasses only need to implement one function.
Instances of the Subclass must be hashable"""
__slots__ = ()
@classmethod
def _get_intermediate_items(cls, item):
"""
Returns:
List of items connected to the given item.
Must be implemented in subclass
"""
raise NotImplementedError("To be implemented in subclass")
def list_traverse(self, *args, **kwargs):
"""
:return: IterableList with the results of the traversal as produced by
traverse()"""
out = IterableList(self._id_attribute_)
out.extend(self.traverse(*args, **kwargs))
return out
def traverse(self, predicate=lambda i, d: True,
prune=lambda i, d: False, depth=-1, branch_first=True,
visit_once=True, ignore_self=1, as_edge=False):
""":return: iterator yielding of items found when traversing self
:param predicate: f(i,d) returns False if item i at depth d should not be included in the result
:param prune:
f(i,d) return True if the search should stop at item i at depth d.
Item i will not be returned.
:param depth:
define at which level the iteration should not go deeper
if -1, there is no limit
if 0, you would effectively only get self, the root of the iteration
i.e. if 1, you would only get the first level of predecessors/successors
:param branch_first:
if True, items will be returned branch first, otherwise depth first
:param visit_once:
if True, items will only be returned once, although they might be encountered
several times. Loops are prevented that way.
:param ignore_self:
if True, self will be ignored and automatically pruned from
the result. Otherwise it will be the first item to be returned.
If as_edge is True, the source of the first edge is None
:param as_edge:
if True, return a pair of items, first being the source, second the
destination, i.e. tuple(src, dest) with the edge spanning from
source to destination"""
visited = set()
stack = Deque()
stack.append((0, self, None)) # self is always depth level 0
def addToStack(stack, item, branch_first, depth):
lst = self._get_intermediate_items(item)
if not lst:
return
if branch_first:
stack.extendleft((depth, i, item) for i in lst)
else:
reviter = ((depth, lst[i], item) for i in range(len(lst) - 1, -1, -1))
stack.extend(reviter)
# END addToStack local method
while stack:
d, item, src = stack.pop() # depth of item, item, item_source
if visit_once and item in visited:
continue
if visit_once:
visited.add(item)
rval = (as_edge and (src, item)) or item
if prune(rval, d):
continue
skipStartItem = ignore_self and (item is self)
if not skipStartItem and predicate(rval, d):
yield rval
# only continue to next level if this is appropriate !
nd = d + 1
if depth > -1 and nd > depth:
continue
addToStack(stack, item, branch_first, nd)
# END for each item on work stack
class Serializable(object):
"""Defines methods to serialize and deserialize objects from and into a data stream"""
__slots__ = ()
def _serialize(self, stream):
"""Serialize the data of this object into the given data stream
:note: a serialized object would ``_deserialize`` into the same object
:param stream: a file-like object
:return: self"""
raise NotImplementedError("To be implemented in subclass")
def _deserialize(self, stream):
"""Deserialize all information regarding this object from the stream
:param stream: a file-like object
:return: self"""
raise NotImplementedError("To be implemented in subclass")