# Copyright (C) 2012-2020 Ben Kurtovic <ben.kurtovic@gmail.com>
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
import html.entities as htmlentities
from ._base import Node
__all__ = ["HTMLEntity"]
[docs]
class HTMLEntity(Node):
"""Represents an HTML entity, like `` ``, either named or unnamed."""
def __init__(self, value, named=None, hexadecimal=False, hex_char="x"):
super().__init__()
self._value = value
if named is None: # Try to guess whether or not the entity is named
try:
int(value)
self._named = False
self._hexadecimal = False
except ValueError:
try:
int(value, 16)
self._named = False
self._hexadecimal = True
except ValueError:
self._named = True
self._hexadecimal = False
else:
self._named = named
self._hexadecimal = hexadecimal
self._hex_char = hex_char
def __str__(self):
if self.named:
return "&{};".format(self.value)
if self.hexadecimal:
return "&#{}{};".format(self.hex_char, self.value)
return "&#{};".format(self.value)
def __strip__(self, **kwargs):
if kwargs.get("normalize"):
return self.normalize()
return self
@property
def value(self):
"""The string value of the HTML entity."""
return self._value
@property
def named(self):
"""Whether the entity is a string name for a codepoint or an integer.
For example, ``Σ``, ``Σ``, and ``Σ`` refer to the same
character, but only the first is "named", while the others are integer
representations of the codepoint.
"""
return self._named
@property
def hexadecimal(self):
"""If unnamed, this is whether the value is hexadecimal or decimal."""
return self._hexadecimal
@property
def hex_char(self):
"""If the value is hexadecimal, this is the letter denoting that.
For example, the hex_char of ``"ሴ"`` is ``"x"``, whereas the
hex_char of ``"ሴ"`` is ``"X"``. Lowercase and uppercase ``x``
are the only values supported.
"""
return self._hex_char
@value.setter
def value(self, newval):
newval = str(newval)
try:
int(newval)
except ValueError:
try:
intval = int(newval, 16)
except ValueError:
if newval not in htmlentities.entitydefs:
raise ValueError(
"entity value {!r} is not a valid name".format(newval)
) from None
self._named = True
self._hexadecimal = False
else:
if intval < 0 or intval > 0x10FFFF:
raise ValueError(
"entity value 0x{:x} is not in range(0x110000)".format(intval)
) from None
self._named = False
self._hexadecimal = True
else:
test = int(newval, 16 if self.hexadecimal else 10)
if test < 0 or test > 0x10FFFF:
raise ValueError(
"entity value {} is not in range(0x110000)".format(test)
)
self._named = False
self._value = newval
@named.setter
def named(self, newval):
newval = bool(newval)
if newval and self.value not in htmlentities.entitydefs:
raise ValueError("entity value {!r} is not a valid name".format(self.value))
if not newval:
try:
int(self.value, 16)
except ValueError as exc:
raise ValueError(
"current entity value {!r} is not a valid "
"Unicode codepoint".format(self.value)
) from exc
self._named = newval
@hexadecimal.setter
def hexadecimal(self, newval):
newval = bool(newval)
if newval and self.named:
raise ValueError("a named entity cannot be hexadecimal")
self._hexadecimal = newval
@hex_char.setter
def hex_char(self, newval):
newval = str(newval)
if newval not in ("x", "X"):
raise ValueError(newval)
self._hex_char = newval
[docs]
def normalize(self):
"""Return the unicode character represented by the HTML entity."""
if self.named:
return chr(htmlentities.name2codepoint[self.value])
if self.hexadecimal:
return chr(int(self.value, 16))
return chr(int(self.value))