# mako/filters.py
# Copyright 2006-2022 the Mako authors and contributors <see AUTHORS file>
#
# This module is part of Mako and is released under
# the MIT License: http://www.opensource.org/licenses/mit-license.php
import codecs
from html.entities import codepoint2name
from html.entities import name2codepoint
import re
from urllib.parse import quote_plus
import markupsafe
html_escape = markupsafe.escape
xml_escapes = {
"&": "&",
">": ">",
"<": "<",
'"': """, # also " in html-only
"'": "'", # also ' in html-only
}
def xml_escape(string):
return re.sub(r'([&<"\'>])', lambda m: xml_escapes[m.group()], string)
def url_escape(string):
# convert into a list of octets
string = string.encode("utf8")
return quote_plus(string)
def trim(string):
return string.strip()
class Decode:
def __getattr__(self, key):
def decode(x):
if isinstance(x, str):
return x
elif not isinstance(x, bytes):
return decode(str(x))
else:
return str(x, encoding=key)
return decode
decode = Decode()
class XMLEntityEscaper:
def __init__(self, codepoint2name, name2codepoint):
self.codepoint2entity = {
c: str("&%s;" % n) for c, n in codepoint2name.items()
}
self.name2codepoint = name2codepoint
def escape_entities(self, text):
"""Replace characters with their character entity references.
Only characters corresponding to a named entity are replaced.
"""
return str(text).translate(self.codepoint2entity)
def __escape(self, m):
codepoint = ord(m.group())
try:
return self.codepoint2entity[codepoint]
except (KeyError, IndexError):
return "&#x%X;" % codepoint
__escapable = re.compile(r'["&<>]|[^\x00-\x7f]')
def escape(self, text):
"""Replace characters with their character references.
Replace characters by their named entity references.
Non-ASCII characters, if they do not have a named entity reference,
are replaced by numerical character references.
The return value is guaranteed to be ASCII.
"""
return self.__escapable.sub(self.__escape, str(text)).encode("ascii")
# XXX: This regexp will not match all valid XML entity names__.
# (It punts on details involving involving CombiningChars and Extenders.)
#
# .. __: http://www.w3.org/TR/2000/REC-xml-20001006#NT-EntityRef
__characterrefs = re.compile(
r"""& (?:
\#(\d+)
| \#x([\da-f]+)
| ( (?!\d) [:\w] [-.:\w]+ )
) ;""",
re.X | re.UNICODE,
)
def __unescape(self, m):
dval, hval, name = m.groups()
if dval:
codepoint = int(dval)
elif hval:
codepoint = int(hval, 16)
else:
codepoint = self.name2codepoint.get(name, 0xFFFD)
# U+FFFD = "REPLACEMENT CHARACTER"
if codepoint < 128:
return chr(codepoint)
return chr(codepoint)
def unescape(self, text):
"""Unescape character references.
All character references (both entity references and numerical
character references) are unescaped.
"""
return self.__characterrefs.sub(self.__unescape, text)
_html_entities_escaper = XMLEntityEscaper(codepoint2name, name2codepoint)
html_entities_escape = _html_entities_escaper.escape_entities
html_entities_unescape = _html_entities_escaper.unescape
def htmlentityreplace_errors(ex):
"""An encoding error handler.
This python codecs error handler replaces unencodable
characters with HTML entities, or, if no HTML entity exists for
the character, XML character references::
>>> 'The cost was \u20ac12.'.encode('latin1', 'htmlentityreplace')
'The cost was €12.'
"""
if isinstance(ex, UnicodeEncodeError):
# Handle encoding errors
bad_text = ex.object[ex.start : ex.end]
text = _html_entities_escaper.escape(bad_text)
return (str(text), ex.end)
raise ex
codecs.register_error("htmlentityreplace", htmlentityreplace_errors)
DEFAULT_ESCAPES = {
"x": "filters.xml_escape",
"h": "filters.html_escape",
"u": "filters.url_escape",
"trim": "filters.trim",
"entity": "filters.html_entities_escape",
"unicode": "str",
"decode": "decode",
"str": "str",
"n": "n",
}
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