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Python

# -*- coding: utf-8 -*-
"""
markupsafe
~~~~~~~~~~
Implements an escape function and a Markup string to replace HTML
special characters with safe representations.
:copyright: 2010 Pallets
:license: BSD-3-Clause
"""
import re
import string
from ._compat import int_types
from ._compat import iteritems
from ._compat import Mapping
from ._compat import PY2
from ._compat import string_types
from ._compat import text_type
from ._compat import unichr
__version__ = "1.1.1"
__all__ = ["Markup", "soft_unicode", "escape", "escape_silent"]
_striptags_re = re.compile(r"(<!--.*?-->|<[^>]*>)")
_entity_re = re.compile(r"&([^& ;]+);")
class Markup(text_type):
"""A string that is ready to be safely inserted into an HTML or XML
document, either because it was escaped or because it was marked
safe.
Passing an object to the constructor converts it to text and wraps
it to mark it safe without escaping. To escape the text, use the
:meth:`escape` class method instead.
>>> Markup('Hello, <em>World</em>!')
Markup('Hello, <em>World</em>!')
>>> Markup(42)
Markup('42')
>>> Markup.escape('Hello, <em>World</em>!')
Markup('Hello &lt;em&gt;World&lt;/em&gt;!')
This implements the ``__html__()`` interface that some frameworks
use. Passing an object that implements ``__html__()`` will wrap the
output of that method, marking it safe.
>>> class Foo:
... def __html__(self):
... return '<a href="/foo">foo</a>'
...
>>> Markup(Foo())
Markup('<a href="/foo">foo</a>')
This is a subclass of the text type (``str`` in Python 3,
``unicode`` in Python 2). It has the same methods as that type, but
all methods escape their arguments and return a ``Markup`` instance.
>>> Markup('<em>%s</em>') % 'foo & bar'
Markup('<em>foo &amp; bar</em>')
>>> Markup('<em>Hello</em> ') + '<foo>'
Markup('<em>Hello</em> &lt;foo&gt;')
"""
__slots__ = ()
def __new__(cls, base=u"", encoding=None, errors="strict"):
if hasattr(base, "__html__"):
base = base.__html__()
if encoding is None:
return text_type.__new__(cls, base)
return text_type.__new__(cls, base, encoding, errors)
def __html__(self):
return self
def __add__(self, other):
if isinstance(other, string_types) or hasattr(other, "__html__"):
return self.__class__(super(Markup, self).__add__(self.escape(other)))
return NotImplemented
def __radd__(self, other):
if hasattr(other, "__html__") or isinstance(other, string_types):
return self.escape(other).__add__(self)
return NotImplemented
def __mul__(self, num):
if isinstance(num, int_types):
return self.__class__(text_type.__mul__(self, num))
return NotImplemented
__rmul__ = __mul__
def __mod__(self, arg):
if isinstance(arg, tuple):
arg = tuple(_MarkupEscapeHelper(x, self.escape) for x in arg)
else:
arg = _MarkupEscapeHelper(arg, self.escape)
return self.__class__(text_type.__mod__(self, arg))
def __repr__(self):
return "%s(%s)" % (self.__class__.__name__, text_type.__repr__(self))
def join(self, seq):
return self.__class__(text_type.join(self, map(self.escape, seq)))
join.__doc__ = text_type.join.__doc__
def split(self, *args, **kwargs):
return list(map(self.__class__, text_type.split(self, *args, **kwargs)))
split.__doc__ = text_type.split.__doc__
def rsplit(self, *args, **kwargs):
return list(map(self.__class__, text_type.rsplit(self, *args, **kwargs)))
rsplit.__doc__ = text_type.rsplit.__doc__
def splitlines(self, *args, **kwargs):
return list(map(self.__class__, text_type.splitlines(self, *args, **kwargs)))
splitlines.__doc__ = text_type.splitlines.__doc__
def unescape(self):
"""Convert escaped markup back into a text string. This replaces
HTML entities with the characters they represent.
>>> Markup('Main &raquo; <em>About</em>').unescape()
'Main » <em>About</em>'
"""
from ._constants import HTML_ENTITIES
def handle_match(m):
name = m.group(1)
if name in HTML_ENTITIES:
return unichr(HTML_ENTITIES[name])
try:
if name[:2] in ("#x", "#X"):
return unichr(int(name[2:], 16))
elif name.startswith("#"):
return unichr(int(name[1:]))
except ValueError:
pass
# Don't modify unexpected input.
return m.group()
return _entity_re.sub(handle_match, text_type(self))
def striptags(self):
""":meth:`unescape` the markup, remove tags, and normalize
whitespace to single spaces.
>>> Markup('Main &raquo;\t<em>About</em>').striptags()
'Main » About'
"""
stripped = u" ".join(_striptags_re.sub("", self).split())
return Markup(stripped).unescape()
@classmethod
def escape(cls, s):
"""Escape a string. Calls :func:`escape` and ensures that for
subclasses the correct type is returned.
"""
rv = escape(s)
if rv.__class__ is not cls:
return cls(rv)
return rv
def make_simple_escaping_wrapper(name): # noqa: B902
orig = getattr(text_type, name)
def func(self, *args, **kwargs):
args = _escape_argspec(list(args), enumerate(args), self.escape)
_escape_argspec(kwargs, iteritems(kwargs), self.escape)
return self.__class__(orig(self, *args, **kwargs))
func.__name__ = orig.__name__
func.__doc__ = orig.__doc__
return func
for method in (
"__getitem__",
"capitalize",
"title",
"lower",
"upper",
"replace",
"ljust",
"rjust",
"lstrip",
"rstrip",
"center",
"strip",
"translate",
"expandtabs",
"swapcase",
"zfill",
):
locals()[method] = make_simple_escaping_wrapper(method)
def partition(self, sep):
return tuple(map(self.__class__, text_type.partition(self, self.escape(sep))))
def rpartition(self, sep):
return tuple(map(self.__class__, text_type.rpartition(self, self.escape(sep))))
def format(self, *args, **kwargs):
formatter = EscapeFormatter(self.escape)
kwargs = _MagicFormatMapping(args, kwargs)
return self.__class__(formatter.vformat(self, args, kwargs))
def __html_format__(self, format_spec):
if format_spec:
raise ValueError("Unsupported format specification " "for Markup.")
return self
# not in python 3
if hasattr(text_type, "__getslice__"):
__getslice__ = make_simple_escaping_wrapper("__getslice__")
del method, make_simple_escaping_wrapper
class _MagicFormatMapping(Mapping):
"""This class implements a dummy wrapper to fix a bug in the Python
standard library for string formatting.
See http://bugs.python.org/issue13598 for information about why
this is necessary.
"""
def __init__(self, args, kwargs):
self._args = args
self._kwargs = kwargs
self._last_index = 0
def __getitem__(self, key):
if key == "":
idx = self._last_index
self._last_index += 1
try:
return self._args[idx]
except LookupError:
pass
key = str(idx)
return self._kwargs[key]
def __iter__(self):
return iter(self._kwargs)
def __len__(self):
return len(self._kwargs)
if hasattr(text_type, "format"):
class EscapeFormatter(string.Formatter):
def __init__(self, escape):
self.escape = escape
def format_field(self, value, format_spec):
if hasattr(value, "__html_format__"):
rv = value.__html_format__(format_spec)
elif hasattr(value, "__html__"):
if format_spec:
raise ValueError(
"Format specifier {0} given, but {1} does not"
" define __html_format__. A class that defines"
" __html__ must define __html_format__ to work"
" with format specifiers.".format(format_spec, type(value))
)
rv = value.__html__()
else:
# We need to make sure the format spec is unicode here as
# otherwise the wrong callback methods are invoked. For
# instance a byte string there would invoke __str__ and
# not __unicode__.
rv = string.Formatter.format_field(self, value, text_type(format_spec))
return text_type(self.escape(rv))
def _escape_argspec(obj, iterable, escape):
"""Helper for various string-wrapped functions."""
for key, value in iterable:
if hasattr(value, "__html__") or isinstance(value, string_types):
obj[key] = escape(value)
return obj
class _MarkupEscapeHelper(object):
"""Helper for Markup.__mod__"""
def __init__(self, obj, escape):
self.obj = obj
self.escape = escape
def __getitem__(self, item):
return _MarkupEscapeHelper(self.obj[item], self.escape)
def __str__(self):
return text_type(self.escape(self.obj))
__unicode__ = __str__
def __repr__(self):
return str(self.escape(repr(self.obj)))
def __int__(self):
return int(self.obj)
def __float__(self):
return float(self.obj)
# we have to import it down here as the speedups and native
# modules imports the markup type which is define above.
try:
from ._speedups import escape, escape_silent, soft_unicode
except ImportError:
from ._native import escape, escape_silent, soft_unicode
if not PY2:
soft_str = soft_unicode
__all__.append("soft_str")