Newton_Editor/plugins/markdown_preview/markdown/postprocessors.py

144 lines
4.6 KiB
Python

# Python Markdown
# A Python implementation of John Gruber's Markdown.
# Documentation: https://python-markdown.github.io/
# GitHub: https://github.com/Python-Markdown/markdown/
# PyPI: https://pypi.org/project/Markdown/
# Started by Manfred Stienstra (http://www.dwerg.net/).
# Maintained for a few years by Yuri Takhteyev (http://www.freewisdom.org).
# Currently maintained by Waylan Limberg (https://github.com/waylan),
# Dmitry Shachnev (https://github.com/mitya57) and Isaac Muse (https://github.com/facelessuser).
# Copyright 2007-2023 The Python Markdown Project (v. 1.7 and later)
# Copyright 2004, 2005, 2006 Yuri Takhteyev (v. 0.2-1.6b)
# Copyright 2004 Manfred Stienstra (the original version)
# License: BSD (see LICENSE.md for details).
"""
Post-processors run on the text of the entire document after is has been serialized into a string.
Postprocessors should be used to work with the text just before output. Usually, they are used add
back sections that were extracted in a preprocessor, fix up outgoing encodings, or wrap the whole
document.
"""
from __future__ import annotations
from collections import OrderedDict
from typing import TYPE_CHECKING, Any
from . import util
import re
if TYPE_CHECKING: # pragma: no cover
from markdown import Markdown
def build_postprocessors(md: Markdown, **kwargs: Any) -> util.Registry[Postprocessor]:
""" Build the default postprocessors for Markdown. """
postprocessors = util.Registry()
postprocessors.register(RawHtmlPostprocessor(md), 'raw_html', 30)
postprocessors.register(AndSubstitutePostprocessor(), 'amp_substitute', 20)
return postprocessors
class Postprocessor(util.Processor):
"""
Postprocessors are run after the ElementTree it converted back into text.
Each Postprocessor implements a `run` method that takes a pointer to a
text string, modifies it as necessary and returns a text string.
Postprocessors must extend `Postprocessor`.
"""
def run(self, text: str) -> str:
"""
Subclasses of `Postprocessor` should implement a `run` method, which
takes the html document as a single text string and returns a
(possibly modified) string.
"""
pass # pragma: no cover
class RawHtmlPostprocessor(Postprocessor):
""" Restore raw html to the document. """
BLOCK_LEVEL_REGEX = re.compile(r'^\<\/?([^ >]+)')
def run(self, text: str):
""" Iterate over html stash and restore html. """
replacements = OrderedDict()
for i in range(self.md.htmlStash.html_counter):
html = self.stash_to_string(self.md.htmlStash.rawHtmlBlocks[i])
if self.isblocklevel(html):
replacements["<p>{}</p>".format(
self.md.htmlStash.get_placeholder(i))] = html
replacements[self.md.htmlStash.get_placeholder(i)] = html
def substitute_match(m):
key = m.group(0)
if key not in replacements:
if key[3:-4] in replacements:
return f'<p>{ replacements[key[3:-4]] }</p>'
else:
return key
return replacements[key]
if replacements:
base_placeholder = util.HTML_PLACEHOLDER % r'([0-9]+)'
pattern = re.compile(f'<p>{ base_placeholder }</p>|{ base_placeholder }')
processed_text = pattern.sub(substitute_match, text)
else:
return text
if processed_text == text:
return processed_text
else:
return self.run(processed_text)
def isblocklevel(self, html: str) -> bool:
""" Check is block of HTML is block-level. """
m = self.BLOCK_LEVEL_REGEX.match(html)
if m:
if m.group(1)[0] in ('!', '?', '@', '%'):
# Comment, PHP etc...
return True
return self.md.is_block_level(m.group(1))
return False
def stash_to_string(self, text: str) -> str:
""" Convert a stashed object to a string. """
return str(text)
class AndSubstitutePostprocessor(Postprocessor):
""" Restore valid entities """
def run(self, text):
text = text.replace(util.AMP_SUBSTITUTE, "&")
return text
@util.deprecated(
"This class is deprecated and will be removed in the future; "
"use [`UnescapeTreeprocessor`][markdown.treeprocessors.UnescapeTreeprocessor] instead."
)
class UnescapePostprocessor(Postprocessor):
""" Restore escaped chars. """
RE = re.compile(r'{}(\d+){}'.format(util.STX, util.ETX))
def unescape(self, m):
return chr(int(m.group(1)))
def run(self, text):
return self.RE.sub(self.unescape, text)