linkchecker/linkcheck/strformat.py
2009-01-08 14:18:03 +00:00

293 lines
8.6 KiB
Python

# -*- coding: iso-8859-1 -*-
# Copyright (C) 2000-2009 Bastian Kleineidam
#
# 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; either version 2 of the License, or
# (at your option) any 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., 675 Mass Ave, Cambridge, MA 02139, USA.
#
# Some functions have been taken and adjusted from the quodlibet
# source. Quodlibet is (C) 2004-2005 Joe Wreschnig, Michael Urman
# and licensed under the GNU General Public License version 2.
"""
Various string utility functions. Note that these functions are not
necessarily optimised for large strings, so use with care.
"""
import re
import textwrap
import codecs
import os
import math
import time
import urlparse
import pydoc
def unicode_safe (s, encoding="iso-8859-1"):
"""Get unicode string without raising encoding errors. Unknown
characters of the given encoding will be ignored.
@param s: the string to be decoded
@type s: any object except None
@return: if s is already unicode, return s unchanged; else return
decoded unicode string of str(s)
@rtype: unicode
"""
assert s is not None, "argument to unicode_safe was None"
if isinstance(s, unicode):
# s is already unicode, nothing to do
return s
return unicode(str(s), encoding, "ignore")
def ascii_safe (s):
"""Get ASCII string without raising encoding errors. Unknown
characters of the given encoding will be ignored.
@param s: the Unicode string to be encoded
@type s: unicode or None
@return: encoded ASCII version of s, or None if s was None
@rtype: string
"""
if isinstance(s, unicode):
s = s.encode('ascii', 'ignore')
return s
def is_ascii (s):
"""Test if a string can be encoded in ASCII."""
try:
s.encode('ascii', 'strict')
return True
except (UnicodeEncodeError, UnicodeDecodeError):
return False
def is_encoding (text):
"""Check if string is a valid encoding."""
try:
return codecs.lookup(text)
except (LookupError, ValueError):
return False
def url_unicode_split (url):
"""Like urlparse.urlsplit(), but always returning unicode parts."""
return [unicode_safe(s) for s in urlparse.urlsplit(url)]
def unquote (s, matching=False):
"""Remove leading and ending single and double quotes.
The quotes need to match if matching is True. Only one quote from each
end will be stripped.
@return: if s evaluates to False, return s as is, else return
string with stripped quotes
@rtype: unquoted string, or s unchanged if it is evaluting to False
"""
if not s:
return s
if len(s) < 2:
return s
if matching:
if s[0] in ("\"'") and s[0] == s[-1]:
s = s[1:-1]
else:
if s[0] in ("\"'"):
s = s[1:]
if s[-1] in ("\"'"):
s = s[:-1]
return s
_para_mac = r"(?:%(sep)s)(?:(?:%(sep)s)\s*)+" % {'sep': '\r'}
_para_posix = r"(?:%(sep)s)(?:(?:%(sep)s)\s*)+" % {'sep': '\n'}
_para_win = r"(?:%(sep)s)(?:(?:%(sep)s)\s*)+" % {'sep': '\r\n'}
_para_ro = re.compile("%s|%s|%s" % (_para_mac, _para_posix, _para_win))
def get_paragraphs (text):
"""A new paragraph is considered to start at a line which follows
one or more blank lines (lines containing nothing or just spaces).
The first line of the text also starts a paragraph."""
if not text:
return []
return _para_ro.split(text)
def wrap (text, width, **kwargs):
"""Adjust lines of text to be not longer than width. The text will be
returned unmodified if width <= 0.
See textwrap.wrap() for a list of supported kwargs.
Returns text with lines no longer than given width."""
if width <= 0 or not text:
return text
ret = []
for para in get_paragraphs(text):
ret.extend(textwrap.wrap(para.strip(), width, **kwargs))
return os.linesep.join(ret)
def indent (text, indent_string=" "):
"""Indent each line of text with the given indent string."""
lines = str(text).splitlines()
return os.linesep.join("%s%s" % (indent_string, x) for x in lines)
def get_line_number (s, index):
r"""Return the line number of s[index] or zero on errors.
Lines are assumed to be separated by the ASCII character '\n'."""
i = 0
if index < 0:
return 0
line = 1
while i < index:
if s[i] == '\n':
line += 1
i += 1
return line
def paginate (text):
"""Print text in pages of lines."""
pydoc.pager(text)
_markup_re = re.compile("<.*?>", re.DOTALL)
def remove_markup (s):
"""Remove all <*> html markup tags from s."""
mo = _markup_re.search(s)
while mo:
s = s[0:mo.start()] + s[mo.end():]
mo = _markup_re.search(s)
return s
def strsize (b):
"""Return human representation of bytes b. A negative number of bytes
raises a value error."""
if b < 0:
raise ValueError("Invalid negative byte number")
if b < 1024:
return u"%dB" % b
if b < 1024 * 10:
return u"%dKB" % int(b / 1024)
if b < 1024 * 1024:
return u"%.2fKB" % (float(b) / 1024)
if b < 1024 * 1024 * 10:
return u"%.2fMB" % (float(b) / (1024*1024))
if b < 1024 * 1024 * 1024:
return u"%.1fMB" % (float(b) / (1024*1024))
if b < 1024 * 1024 * 1024 * 10:
return u"%.2fGB" % (float(b) / (1024*1024*1024))
return u"%.1fGB" % (float(b) / (1024*1024*1024))
def strtime (t):
"""Return ISO 8601 formatted time."""
return time.strftime("%Y-%m-%d %H:%M:%S", time.localtime(t)) + \
strtimezone()
# from quodlibet
def strduration (duration):
"""Turn a time value in seconds into hh:mm:ss or mm:ss."""
if duration < 0:
duration = abs(duration)
prefix = "-"
else:
prefix = ""
duration = math.ceil(duration)
if duration >= 3600: # 1 hour
# time, in hours:minutes:seconds
return "%s%02d:%02d:%02d" % (prefix, duration // 3600,
(duration % 3600) // 60, duration % 60)
else:
# time, in minutes:seconds
return "%s%02d:%02d" % (prefix, duration // 60, duration % 60)
# from quodlibet
def strduration_long (duration):
"""Turn a time value in seconds into x hours, x minutes, etc."""
if duration < 0:
duration = abs(duration)
prefix = "-"
else:
prefix = ""
if duration < 1:
return _("%(prefix)s%(duration).02f seconds") % \
{"prefix": prefix, "duration": duration}
# translation dummies
_n("%d second", "%d seconds", 1)
_n("%d minute", "%d minutes", 1)
_n("%d hour", "%d hours", 1)
_n("%d day", "%d days", 1)
_n("%d year", "%d years", 1)
cutoffs = [
(60, "%d second", "%d seconds"),
(60, "%d minute", "%d minutes"),
(24, "%d hour", "%d hours"),
(365, "%d day", "%d days"),
(None, "%d year", "%d years"),
]
time_str = []
for divisor, single, plural in cutoffs:
if duration < 1:
break
if divisor is None:
duration, unit = 0, duration
else:
duration, unit = divmod(duration, divisor)
if unit:
time_str.append(_n(single, plural, unit) % unit)
time_str.reverse()
if len(time_str) > 2:
time_str.pop()
return "%s%s" % (prefix, ", ".join(time_str))
def strtimezone ():
"""Return timezone info, %z on some platforms, but not supported on all.
"""
if time.daylight:
zone = time.altzone
else:
zone = time.timezone
return "%+04d" % int(-zone/3600)
_sub_ws = re.compile(r"\s+").sub
def stripall (s):
"""Remove all whitespace from given string."""
if not s:
return s
return _sub_ws("", s)
def limit (s, length=72):
"""If the length of the string exceeds the given limit, it will be cut
off and three dots will be appended.
@param s: the string to limit
@type s: string
@param length: maximum length
@type length: non-negative integer
@return: limited string, at most length+3 characters long
"""
assert length >= 0, "length limit must be a non-negative integer"
if not s or len(s) <= length:
return s
if length == 0:
return ""
return "%s..." % s[:length]