datatracker/ietf/utils/text.py
2017-06-06 16:30:53 +00:00

124 lines
4.2 KiB
Python

from __future__ import unicode_literals
import re
import unicodedata
import textwrap
import types
from django.utils.functional import allow_lazy
from django.utils import six
from django.utils.safestring import mark_safe
import debug # pyflakes:ignore
def xslugify(value):
"""
Converts to ASCII. Converts spaces to hyphens. Removes characters that
aren't alphanumerics, underscores, slash, or hyphens. Converts to
lowercase. Also strips leading and trailing whitespace.
(I.e., does the same as slugify, but also converts slashes to dashes.)
"""
value = unicodedata.normalize('NFKD', value).encode('ascii', 'ignore').decode('ascii')
value = re.sub('[^\w\s/-]', '', value).strip().lower()
return mark_safe(re.sub('[-\s/]+', '-', value))
xslugify = allow_lazy(xslugify, six.text_type)
def strip_prefix(text, prefix):
if text.startswith(prefix):
return text[len(prefix):]
else:
return text
def strip_suffix(text, suffix):
if text.endswith(suffix):
return text[:-len(suffix)]
else:
return text
def fill(text, width):
"""Wraps each paragraph in text (a string) so every line
is at most width characters long, and returns a single string
containing the wrapped paragraph.
"""
width = int(width)
paras = text.replace("\r\n","\n").replace("\r","\n").split("\n\n")
wrapped = []
for para in paras:
if para:
lines = para.split("\n")
maxlen = max([len(line) for line in lines])
if maxlen > width:
para = textwrap.fill(para, width, replace_whitespace=False)
wrapped.append(para)
return "\n\n".join(wrapped)
def wordwrap(text, width=80):
"""Wraps long lines without loosing the formatting and indentation
of short lines"""
if not isinstance(text, (types.StringType,types.UnicodeType)):
return text
text = re.sub(" *\r\n", "\n", text) # get rid of DOS line endings
text = re.sub(" *\r", "\n", text) # get rid of MAC line endings
text = re.sub("( *\n){3,}", "\n\n", text) # get rid of excessive vertical whitespace
lines = text.split("\n")
filled = []
wrapped = False
prev_indent = None
for line in lines:
line = line.expandtabs().rstrip()
indent = " " * (len(line) - len(line.lstrip()))
ind = len(indent)
if wrapped and line.strip() != "" and indent == prev_indent:
line = filled[-1] + " " + line.lstrip()
filled = filled[:-1]
else:
wrapped = False
while (len(line) > width) and (" " in line[ind:]):
linelength = len(line)
wrapped = True
breakpoint = line.rfind(" ",ind,width)
if breakpoint == -1:
breakpoint = line.find(" ", ind)
filled += [ line[:breakpoint] ]
line = indent + line[breakpoint+1:]
if len(line) >= linelength:
break
filled += [ line.rstrip() ]
prev_indent = indent
return "\n".join(filled)
# def alternative_wrap(text, width=80):
# # From http://blog.belgoat.com/python-textwrap-wrap-your-text-to-terminal-size/
# textLines = text.split('\n')
# wrapped_lines = []
# # Preserve any indent (after the general indent)
# for line in textLines:
# preservedIndent = ''
# existIndent = re.search(r'^(\W+)', line)
# # Change the existing wrap indent to the original one
# if (existIndent):
# preservedIndent = existIndent.groups()[0]
# wrapped_lines.append(textwrap.fill(line, width=width, subsequent_indent=preservedIndent))
# text = '\n'.join(wrapped_lines)
# return text
def wrap_text_if_unwrapped(text, width=80, max_tolerated_line_length=100):
text = re.sub(" *\r\n", "\n", text) # get rid of DOS line endings
text = re.sub(" *\r", "\n", text) # get rid of MAC line endings
contains_long_lines = any(" " in l and len(l) > max_tolerated_line_length
for l in text.split("\n"))
if contains_long_lines:
text = wordwrap(text, width)
return text
def isascii(text):
try:
text.encode('ascii')
return True
except UnicodeEncodeError:
return False