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markdown2.py
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#!/usr/bin/env python
# Copyright (c) 2012 Trent Mick.
# Copyright (c) 2007-2008 ActiveState Corp.
# License: MIT (http://www.opensource.org/licenses/mit-license.php)
r"""A fast and complete Python implementation of Markdown.
[from http://daringfireball.net/projects/markdown/]
> Markdown is a text-to-HTML filter; it translates an easy-to-read /
> easy-to-write structured text format into HTML. Markdown's text
> format is most similar to that of plain text email, and supports
> features such as headers, *emphasis*, code blocks, blockquotes, and
> links.
>
> Markdown's syntax is designed not as a generic markup language, but
> specifically to serve as a front-end to (X)HTML. You can use span-level
> HTML tags anywhere in a Markdown document, and you can use block level
> HTML tags (like <div> and <table> as well).
Module usage:
>>> import markdown2
>>> markdown2.markdown("*boo!*") # or use `html = markdown_path(PATH)`
u'<p><em>boo!</em></p>\n'
>>> markdowner = Markdown()
>>> markdowner.convert("*boo!*")
u'<p><em>boo!</em></p>\n'
>>> markdowner.convert("**boom!**")
u'<p><strong>boom!</strong></p>\n'
This implementation of Markdown implements the full "core" syntax plus a
number of extras (e.g., code syntax coloring, footnotes) as described on
<https://github.com/trentm/python-markdown2/wiki/Extras>.
"""
cmdln_desc = """A fast and complete Python implementation of Markdown, a
text-to-HTML conversion tool for web writers.
Supported extra syntax options (see -x|--extras option below and
see <https://github.com/trentm/python-markdown2/wiki/Extras> for details):
* admonitions: Enable parsing of RST admonitions.
* breaks: Control where hard breaks are inserted in the markdown.
Options include:
- on_newline: Replace single new line characters with <br> when True
- on_backslash: Replace backslashes at the end of a line with <br>
* break-on-newline: Alias for the on_newline option in the breaks extra.
* code-friendly: Disable _ and __ for em and strong.
* cuddled-lists: Allow lists to be cuddled to the preceding paragraph.
* fenced-code-blocks: Allows a code block to not have to be indented
by fencing it with '```' on a line before and after. Based on
<http://github.github.com/github-flavored-markdown/> with support for
syntax highlighting.
* footnotes: Support footnotes as in use on daringfireball.net and
implemented in other Markdown processors (tho not in Markdown.pl v1.0.1).
* header-ids: Adds "id" attributes to headers. The id value is a slug of
the header text.
* highlightjs-lang: Allows specifying the language which used for syntax
highlighting when using fenced-code-blocks and highlightjs.
* html-classes: Takes a dict mapping html tag names (lowercase) to a
string to use for a "class" tag attribute. Currently only supports "img",
"table", "thead", "pre", "code", "ul" and "ol" tags. Add an issue if you require
this for other tags.
* link-patterns: Auto-link given regex patterns in text (e.g. bug number
references, revision number references).
* link-shortrefs: allow shortcut reference links, not followed by `[]` or
a link label.
* markdown-in-html: Allow the use of `markdown="1"` in a block HTML tag to
have markdown processing be done on its contents. Similar to
<http://michelf.com/projects/php-markdown/extra/#markdown-attr> but with
some limitations.
* metadata: Extract metadata from a leading '---'-fenced block.
See <https://github.com/trentm/python-markdown2/issues/77> for details.
* middle-word-em: Allows or disallows emphasis syntax in the middle of words,
defaulting to allow. Disabling this means that `this_text_here` will not be
converted to `this<em>text</em>here`.
* nofollow: Add `rel="nofollow"` to add `<a>` tags with an href. See
<http://en.wikipedia.org/wiki/Nofollow>.
* numbering: Support of generic counters. Non standard extension to
allow sequential numbering of figures, tables, equations, exhibits etc.
* pyshell: Treats unindented Python interactive shell sessions as <code>
blocks.
* smarty-pants: Replaces ' and " with curly quotation marks or curly
apostrophes. Replaces --, ---, ..., and . . . with en dashes, em dashes,
and ellipses.
* spoiler: A special kind of blockquote commonly hidden behind a
click on SO. Syntax per <http://meta.stackexchange.com/a/72878>.
* strike: text inside of double tilde is ~~strikethrough~~
* tag-friendly: Requires atx style headers to have a space between the # and
the header text. Useful for applications that require twitter style tags to
pass through the parser.
* tables: Tables using the same format as GFM
<https://help.github.com/articles/github-flavored-markdown#tables> and
PHP-Markdown Extra <https://michelf.ca/projects/php-markdown/extra/#table>.
* toc: The returned HTML string gets a new "toc_html" attribute which is
a Table of Contents for the document. (experimental)
* use-file-vars: Look for an Emacs-style markdown-extras file variable to turn
on Extras.
* wiki-tables: Google Code Wiki-style tables. See
<http://code.google.com/p/support/wiki/WikiSyntax#Tables>.
* wavedrom: Support for generating Wavedrom digital timing diagrams
* xml: Passes one-liner processing instructions and namespaced XML tags.
"""
# Dev Notes:
# - Python's regex syntax doesn't have '\z', so I'm using '\Z'. I'm
# not yet sure if there implications with this. Compare 'pydoc sre'
# and 'perldoc perlre'.
__version_info__ = (2, 5, 3)
__version__ = '.'.join(map(str, __version_info__))
__author__ = "Trent Mick"
import argparse
import codecs
import logging
import re
import sys
from collections import defaultdict, OrderedDict
from abc import ABC, abstractmethod
import functools
from collections.abc import Iterable
from hashlib import sha256
from random import random
from typing import Any, Callable, Dict, List, Literal, Optional, Tuple, Type, TypedDict, Union
from collections.abc import Collection
from enum import IntEnum, auto
from os import urandom
# ---- type defs
_safe_mode = Literal['replace', 'escape']
_extras_dict = dict[str, Any]
_extras_param = Union[list[str], _extras_dict]
_link_patterns = Iterable[tuple[re.Pattern, Union[str, Callable[[re.Match], str]]]]
# ---- globals
DEBUG = False
log = logging.getLogger("markdown")
DEFAULT_TAB_WIDTH = 4
SECRET_SALT = urandom(16)
# MD5 function was previously used for this; the "md5" prefix was kept for
# backwards compatibility.
def _hash_text(s: str) -> str:
return 'md5-' + sha256(SECRET_SALT + s.encode("utf-8")).hexdigest()[32:]
# Table of hash values for escaped characters:
g_escape_table = {ch: _hash_text(ch)
for ch in '\\`*_{}[]()>#+-.!'}
# Ampersand-encoding based entirely on Nat Irons's Amputator MT plugin:
# http://bumppo.net/projects/amputator/
_AMPERSAND_RE = re.compile(r'&(?!#?[xX]?(?:[0-9a-fA-F]+|\w+);)')
# ---- exceptions
class MarkdownError(Exception):
pass
# ---- public api
def markdown_path(
path: str,
encoding: str = "utf-8",
html4tags: bool = False,
tab_width: int = DEFAULT_TAB_WIDTH,
safe_mode: Optional[_safe_mode] = None,
extras: Optional[_extras_param] = None,
link_patterns: Optional[_link_patterns] = None,
footnote_title: Optional[str] = None,
footnote_return_symbol: Optional[str] = None,
use_file_vars: bool = False
) -> 'UnicodeWithAttrs':
fp = codecs.open(path, 'r', encoding)
text = fp.read()
fp.close()
return Markdown(html4tags=html4tags, tab_width=tab_width,
safe_mode=safe_mode, extras=extras,
link_patterns=link_patterns,
footnote_title=footnote_title,
footnote_return_symbol=footnote_return_symbol,
use_file_vars=use_file_vars).convert(text)
def markdown(
text: str,
html4tags: bool = False,
tab_width: int = DEFAULT_TAB_WIDTH,
safe_mode: Optional[_safe_mode] = None,
extras: Optional[_extras_param] = None,
link_patterns: Optional[_link_patterns] = None,
footnote_title: Optional[str] = None,
footnote_return_symbol: Optional[str] =None,
use_file_vars: bool = False,
cli: bool = False
) -> 'UnicodeWithAttrs':
return Markdown(html4tags=html4tags, tab_width=tab_width,
safe_mode=safe_mode, extras=extras,
link_patterns=link_patterns,
footnote_title=footnote_title,
footnote_return_symbol=footnote_return_symbol,
use_file_vars=use_file_vars, cli=cli).convert(text)
class Stage(IntEnum):
PREPROCESS = auto()
HASH_HTML = auto()
LINK_DEFS = auto()
BLOCK_GAMUT = auto()
HEADERS = auto()
LISTS = auto()
CODE_BLOCKS = auto()
BLOCK_QUOTES = auto()
PARAGRAPHS = auto()
SPAN_GAMUT = auto()
CODE_SPANS = auto()
ESCAPE_SPECIAL = auto()
LINKS = auto() # and auto links
ITALIC_AND_BOLD = auto()
POSTPROCESS = auto()
UNHASH_HTML = auto()
def mark_stage(stage: Stage):
'''
Decorator that handles executing relevant `Extra`s before and after this `Stage` executes.
'''
def wrapper(func):
@functools.wraps(func)
def inner(md: 'Markdown', text, *args, **kwargs):
md.stage = stage
# set "order" prop so extras can tell if they're being invoked before/after the stage
md.order = stage - 0.5
if stage in Extra._exec_order:
for klass in Extra._exec_order[stage][0]:
if klass.name not in md.extra_classes:
continue
extra = md.extra_classes[klass.name]
if extra.test(text):
text = extra.run(text)
md.order = stage
text = func(md, text, *args, **kwargs)
md.order = stage + 0.5
if stage in Extra._exec_order:
for klass in Extra._exec_order[stage][1]:
if klass.name not in md.extra_classes:
continue
extra = md.extra_classes[klass.name]
if extra.test(text):
text = extra.run(text)
return text
return inner
return wrapper
class Markdown:
# The dict of "extras" to enable in processing -- a mapping of
# extra name to argument for the extra. Most extras do not have an
# argument, in which case the value is None.
#
# This can be set via (a) subclassing and (b) the constructor
# "extras" argument.
extras: _extras_dict
# dict of `Extra` names and associated class instances, populated during _setup_extras
extra_classes: dict[str, 'Extra']
urls: dict[str, str]
titles: dict[str, str]
html_blocks: dict[str, str]
html_spans: dict[str, str]
html_removed_text: str = "{(#HTML#)}" # placeholder removed text that does not trigger bold
html_removed_text_compat: str = "[HTML_REMOVED]" # for compat with markdown.py
safe_mode: Optional[_safe_mode]
_toc: list[tuple[int, str, str]]
# Used to track when we're inside an ordered or unordered list
# (see _ProcessListItems() for details):
list_level = 0
stage: Stage
'''Current "stage" of markdown conversion taking place'''
order: float
'''
Same as `Stage` but will be +/- 0.5 of the value of `Stage`.
This allows extras to check if they are running before or after a particular stage
with `if md.order < md.stage`.
'''
_ws_only_line_re = re.compile(r"^[ \t]+$", re.M)
def __init__(
self,
html4tags: bool = False,
tab_width: int = DEFAULT_TAB_WIDTH,
safe_mode: Optional[_safe_mode] = None,
extras: Optional[_extras_param] = None,
link_patterns: Optional[_link_patterns] = None,
footnote_title: Optional[str] = None,
footnote_return_symbol: Optional[str] = None,
use_file_vars: bool = False,
cli: bool = False
):
if html4tags:
self.empty_element_suffix = ">"
else:
self.empty_element_suffix = " />"
self.tab_width = tab_width
self.tab = tab_width * " "
# For compatibility with earlier markdown2.py and with
# markdown.py's safe_mode being a boolean,
# safe_mode == True -> "replace"
if safe_mode is True:
self.safe_mode = "replace"
else:
self.safe_mode = safe_mode
# Massaging and building the "extras" info.
if getattr(self, 'extras', None) is None:
self.extras = {}
elif not isinstance(self.extras, dict):
# inheriting classes may set `self.extras` as List[str].
# we can't allow it through type hints but we can convert it
self.extras = {e: None for e in self.extras} # type:ignore
if extras:
if not isinstance(extras, dict):
extras = {e: None for e in extras}
self.extras.update(extras)
assert isinstance(self.extras, dict)
if "toc" in self.extras:
if "header-ids" not in self.extras:
self.extras["header-ids"] = None # "toc" implies "header-ids"
if self.extras["toc"] is None:
self._toc_depth = 6
else:
self._toc_depth = self.extras["toc"].get("depth", 6)
if 'header-ids' in self.extras:
if not isinstance(self.extras['header-ids'], dict):
self.extras['header-ids'] = {
'mixed': False,
'prefix': self.extras['header-ids'],
'reset-count': True
}
if 'break-on-newline' in self.extras:
self.extras.setdefault('breaks', {})
self.extras['breaks']['on_newline'] = True
if 'link-patterns' in self.extras:
# allow link patterns via extras dict without kwarg explicitly set
link_patterns = link_patterns or self.extras['link-patterns']
if link_patterns is None:
# if you have specified that the link-patterns extra SHOULD
# be used (via self.extras) but you haven't provided anything
# via the link_patterns argument then an error is raised
raise MarkdownError("If the 'link-patterns' extra is used, an argument for 'link_patterns' is required")
self.extras['link-patterns'] = link_patterns
self._instance_extras = self.extras.copy()
self.link_patterns = link_patterns
self.footnote_title = footnote_title
self.footnote_return_symbol = footnote_return_symbol
self.use_file_vars = use_file_vars
self._outdent_re = re.compile(r'^(\t|[ ]{1,%d})' % tab_width, re.M)
self.cli = cli
self._escape_table = g_escape_table.copy()
self._code_table = {}
if "smarty-pants" in self.extras:
self._escape_table['"'] = _hash_text('"')
self._escape_table["'"] = _hash_text("'")
def reset(self):
self.urls = {}
self.titles = {}
self.html_blocks = {}
self.html_spans = {}
self.list_level = 0
self.extras = self._instance_extras.copy()
self._setup_extras()
self._toc = []
def _setup_extras(self):
if "footnotes" in self.extras:
# order of insertion matters for footnotes. Use ordered dict for Python < 3.7
# https://docs.python.org/3/whatsnew/3.7.html#summary-release-highlights
self.footnotes = OrderedDict()
self.footnote_ids = []
self._footnote_marker = _hash_text('<<footnote>>')
if "header-ids" in self.extras:
if not hasattr(self, '_count_from_header_id') or self.extras['header-ids'].get('reset-count', False):
self._count_from_header_id = defaultdict(int)
if "metadata" in self.extras:
self.metadata: dict[str, Any] = {}
self.extra_classes = {}
for name, klass in Extra._registry.items():
if name not in self.extras:
continue
self.extra_classes[name] = klass(self, (self.extras.get(name, {})))
# Per <https://developer.mozilla.org/en-US/docs/HTML/Element/a> "rel"
# should only be used in <a> tags with an "href" attribute.
# Opens the linked document in a new window or tab
# should only used in <a> tags with an "href" attribute.
# same with _a_nofollow
_a_nofollow_or_blank_links = re.compile(r"""
<(a)
(
[^>]*
href= # href is required
['"]? # HTML5 attribute values do not have to be quoted
[^#'"] # We don't want to match href values that start with # (like footnotes)
)
""",
re.IGNORECASE | re.VERBOSE
)
def convert(self, text: str) -> 'UnicodeWithAttrs':
"""Convert the given text."""
# Main function. The order in which other subs are called here is
# essential. Link and image substitutions need to happen before
# _EscapeSpecialChars(), so that any *'s or _'s in the <a>
# and <img> tags get encoded.
# Clear the global hashes. If we don't clear these, you get conflicts
# from other articles when generating a page which contains more than
# one article (e.g. an index page that shows the N most recent
# articles):
self.reset()
if not isinstance(text, str):
# TODO: perhaps shouldn't presume UTF-8 for string input?
text = str(text, 'utf-8')
if self.use_file_vars:
# Look for emacs-style file variable hints.
text = self._emacs_oneliner_vars_pat.sub(self._emacs_vars_oneliner_sub, text)
emacs_vars = self._get_emacs_vars(text)
if "markdown-extras" in emacs_vars:
splitter = re.compile("[ ,]+")
for e in splitter.split(emacs_vars["markdown-extras"]):
if '=' in e:
ename, earg = e.split('=', 1)
try:
earg = int(earg)
except ValueError:
pass
else:
ename, earg = e, None
self.extras[ename] = earg
self._setup_extras()
# Standardize line endings:
text = text.replace("\r\n", "\n")
text = text.replace("\r", "\n")
# Make sure $text ends with a couple of newlines:
text += "\n\n"
# Convert all tabs to spaces.
text = self._detab(text)
# Strip any lines consisting only of spaces and tabs.
# This makes subsequent regexen easier to write, because we can
# match consecutive blank lines with /\n+/ instead of something
# contorted like /[ \t]*\n+/ .
text = self._ws_only_line_re.sub("", text)
# strip metadata from head and extract
if "metadata" in self.extras:
text = self._extract_metadata(text)
text = self.preprocess(text)
if self.safe_mode:
text = self._hash_html_spans(text)
# Turn block-level HTML blocks into hash entries
text = self._hash_html_blocks(text, raw=True)
# Strip link definitions, store in hashes.
if "footnotes" in self.extras:
# Must do footnotes first because an unlucky footnote defn
# looks like a link defn:
# [^4]: this "looks like a link defn"
text = self._strip_footnote_definitions(text)
text = self._strip_link_definitions(text)
text = self._run_block_gamut(text)
if "footnotes" in self.extras:
def footnote_sub(match):
normed_id = match.group(1)
self.footnote_ids.append(normed_id)
return str(len(self.footnote_ids))
text = re.sub(r'%s-(.*?)(?=</a></sup>)' % self._footnote_marker, footnote_sub, text)
text = self._add_footnotes(text)
text = self.postprocess(text)
text = self._unescape_special_chars(text)
text = self._unhash_html_spans(text)
if self.safe_mode:
# return the removed text warning to its markdown.py compatible form
text = text.replace(self.html_removed_text, self.html_removed_text_compat)
do_target_blank_links = "target-blank-links" in self.extras
do_nofollow_links = "nofollow" in self.extras
if do_target_blank_links and do_nofollow_links:
text = self._a_nofollow_or_blank_links.sub(r'<\1 rel="nofollow noopener" target="_blank"\2', text)
elif do_target_blank_links:
text = self._a_nofollow_or_blank_links.sub(r'<\1 rel="noopener" target="_blank"\2', text)
elif do_nofollow_links:
text = self._a_nofollow_or_blank_links.sub(r'<\1 rel="nofollow"\2', text)
if "toc" in self.extras and self._toc:
if self.extras['header-ids'].get('mixed'):
# TOC will only be out of order if mixed headers is enabled
def toc_sort(entry):
'''Sort the TOC by order of appearance in text'''
match = re.search(
# header tag, any attrs, the ID, any attrs, the text, close tag
r'^<(h%d).*?id=(["\'])%s\2.*>%s</\1>$' % (entry[0], entry[1], re.escape(entry[2])),
text, re.M
)
return match.start() if match else 0
self._toc.sort(key=toc_sort)
self._toc_html = calculate_toc_html(self._toc)
# Prepend toc html to output
if self.cli or (self.extras['toc'] is not None and self.extras['toc'].get('prepend', False)):
text = f'{self._toc_html}\n{text}'
text += "\n"
# Attach attrs to output
rv = UnicodeWithAttrs(text)
if "toc" in self.extras and self._toc:
rv.toc_html = self._toc_html
if "metadata" in self.extras:
rv.metadata = self.metadata
return rv
@mark_stage(Stage.POSTPROCESS)
def postprocess(self, text: str) -> str:
"""A hook for subclasses to do some postprocessing of the html, if
desired. This is called before unescaping of special chars and
unhashing of raw HTML spans.
"""
return text
@mark_stage(Stage.PREPROCESS)
def preprocess(self, text: str) -> str:
"""A hook for subclasses to do some preprocessing of the Markdown, if
desired. This is called after basic formatting of the text, but prior
to any extras, safe mode, etc. processing.
"""
return text
# Is metadata if the content starts with optional '---'-fenced `key: value`
# pairs. E.g. (indented for presentation):
# ---
# foo: bar
# another-var: blah blah
# ---
# # header
# or:
# foo: bar
# another-var: blah blah
#
# # header
_meta_data_pattern = re.compile(r'''
^{0}( # optional opening fence
(?:
{1}:(?:\n+[ \t]+.*)+ # indented lists
)|(?:
(?:{1}:\s+>(?:\n\s+.*)+?) # multiline long descriptions
(?=\n{1}:\s*.*\n|\s*\Z) # match up until the start of the next key:value definition or the end of the input text
)|(?:
{1}:(?! >).*\n? # simple key:value pair, leading spaces allowed
)
){0} # optional closing fence
'''.format(r'(?:---[\ \t]*\n)?', r'[\S \t]*\w[\S \t]*\s*'), re.MULTILINE | re.VERBOSE
)
_key_val_list_pat = re.compile(
r"^-(?:[ \t]*([^\n]*)(?:[ \t]*[:-][ \t]*(\S+))?)(?:\n((?:[ \t]+[^\n]+\n?)+))?",
re.MULTILINE,
)
_key_val_dict_pat = re.compile(
r"^([^:\n]+)[ \t]*:[ \t]*([^\n]*)(?:((?:\n[ \t]+[^\n]+)+))?", re.MULTILINE
) # grp0: key, grp1: value, grp2: multiline value
_meta_data_fence_pattern = re.compile(r'^---[\ \t]*\n', re.MULTILINE)
_meta_data_newline = re.compile("^\n", re.MULTILINE)
def _extract_metadata(self, text: str) -> str:
if text.startswith("---"):
fence_splits = re.split(self._meta_data_fence_pattern, text, maxsplit=2)
metadata_content = fence_splits[1]
tail = fence_splits[2]
else:
metadata_split = re.split(self._meta_data_newline, text, maxsplit=1)
metadata_content = metadata_split[0]
tail = metadata_split[1]
# _meta_data_pattern only has one capturing group, so we can assume
# the returned type to be list[str]
match: list[str] = re.findall(self._meta_data_pattern, metadata_content)
if not match:
return text
def parse_structured_value(value: str) -> Union[list[Any], dict[str, Any]]:
vs = value.lstrip()
vs = value.replace(v[: len(value) - len(vs)], "\n")[1:]
# List
if vs.startswith("-"):
r: list[Any] = []
# the regex used has multiple capturing groups, so
# returned type from findall will be List[List[str]]
match: list[str]
for match in re.findall(self._key_val_list_pat, vs):
if match[0] and not match[1] and not match[2]:
r.append(match[0].strip())
elif match[0] == ">" and not match[1] and match[2]:
r.append(match[2].strip())
elif match[0] and match[1]:
r.append({match[0].strip(): match[1].strip()})
elif not match[0] and not match[1] and match[2]:
r.append(parse_structured_value(match[2]))
else:
# Broken case
pass
return r
# Dict
else:
return {
match[0].strip(): (
match[1].strip()
if match[1]
else parse_structured_value(match[2])
)
for match in re.findall(self._key_val_dict_pat, vs)
}
for item in match:
k, v = item.split(":", 1)
# Multiline value
if v[:3] == " >\n":
self.metadata[k.strip()] = _dedent(v[3:]).strip()
# Empty value
elif v == "\n":
self.metadata[k.strip()] = ""
# Structured value
elif v[0] == "\n":
self.metadata[k.strip()] = parse_structured_value(v)
# Simple value
else:
self.metadata[k.strip()] = v.strip()
return tail
_emacs_oneliner_vars_pat = re.compile(r"((?:<!--)?\s*-\*-)\s*(?:(\S[^\r\n]*?)([\r\n]\s*)?)?(-\*-\s*(?:-->)?)", re.UNICODE)
# This regular expression is intended to match blocks like this:
# PREFIX Local Variables: SUFFIX
# PREFIX mode: Tcl SUFFIX
# PREFIX End: SUFFIX
# Some notes:
# - "[ \t]" is used instead of "\s" to specifically exclude newlines
# - "(\r\n|\n|\r)" is used instead of "$" because the sre engine does
# not like anything other than Unix-style line terminators.
_emacs_local_vars_pat = re.compile(r"""^
(?P<prefix>(?:[^\r\n|\n|\r])*?)
[\ \t]*Local\ Variables:[\ \t]*
(?P<suffix>.*?)(?:\r\n|\n|\r)
(?P<content>.*?\1End:)
""", re.IGNORECASE | re.MULTILINE | re.DOTALL | re.VERBOSE)
def _emacs_vars_oneliner_sub(self, match: re.Match) -> str:
if match.group(1).strip() == '-*-' and match.group(4).strip() == '-*-':
lead_ws = re.findall(r'^\s*', match.group(1))[0]
tail_ws = re.findall(r'\s*$', match.group(4))[0]
return '{}<!-- {} {} {} -->{}'.format(lead_ws, '-*-', match.group(2).strip(), '-*-', tail_ws)
start, end = match.span()
return match.string[start: end]
def _get_emacs_vars(self, text: str) -> dict[str, str]:
"""Return a dictionary of emacs-style local variables.
Parsing is done loosely according to this spec (and according to
some in-practice deviations from this):
http://www.gnu.org/software/emacs/manual/html_node/emacs/Specifying-File-Variables.html#Specifying-File-Variables
"""
emacs_vars = {}
SIZE = pow(2, 13) # 8kB
# Search near the start for a '-*-'-style one-liner of variables.
head = text[:SIZE]
if "-*-" in head:
match = self._emacs_oneliner_vars_pat.search(head)
if match:
emacs_vars_str = match.group(2)
assert '\n' not in emacs_vars_str
emacs_var_strs = [s.strip() for s in emacs_vars_str.split(';')
if s.strip()]
if len(emacs_var_strs) == 1 and ':' not in emacs_var_strs[0]:
# While not in the spec, this form is allowed by emacs:
# -*- Tcl -*-
# where the implied "variable" is "mode". This form
# is only allowed if there are no other variables.
emacs_vars["mode"] = emacs_var_strs[0].strip()
else:
for emacs_var_str in emacs_var_strs:
try:
variable, value = emacs_var_str.strip().split(':', 1)
except ValueError:
log.debug("emacs variables error: malformed -*- "
"line: %r", emacs_var_str)
continue
# Lowercase the variable name because Emacs allows "Mode"
# or "mode" or "MoDe", etc.
emacs_vars[variable.lower()] = value.strip()
tail = text[-SIZE:]
if "Local Variables" in tail:
match = self._emacs_local_vars_pat.search(tail)
if match:
prefix = match.group("prefix")
suffix = match.group("suffix")
lines = match.group("content").splitlines(False)
# print "prefix=%r, suffix=%r, content=%r, lines: %s"\
# % (prefix, suffix, match.group("content"), lines)
# Validate the Local Variables block: proper prefix and suffix
# usage.
for i, line in enumerate(lines):
if not line.startswith(prefix):
log.debug("emacs variables error: line '%s' "
"does not use proper prefix '%s'"
% (line, prefix))
return {}
# Don't validate suffix on last line. Emacs doesn't care,
# neither should we.
if i != len(lines)-1 and not line.endswith(suffix):
log.debug("emacs variables error: line '%s' "
"does not use proper suffix '%s'"
% (line, suffix))
return {}
# Parse out one emacs var per line.
continued_for = None
for line in lines[:-1]: # no var on the last line ("PREFIX End:")
if prefix:
line = line[len(prefix):] # strip prefix
if suffix:
line = line[:-len(suffix)] # strip suffix
line = line.strip()
if continued_for:
variable = continued_for
if line.endswith('\\'):
line = line[:-1].rstrip()
else:
continued_for = None
emacs_vars[variable] += ' ' + line
else:
try:
variable, value = line.split(':', 1)
except ValueError:
log.debug("local variables error: missing colon "
"in local variables entry: '%s'" % line)
continue
# Do NOT lowercase the variable name, because Emacs only
# allows "mode" (and not "Mode", "MoDe", etc.) in this block.
value = value.strip()
if value.endswith('\\'):
value = value[:-1].rstrip()
continued_for = variable
else:
continued_for = None
emacs_vars[variable] = value
# Unquote values.
for var, val in list(emacs_vars.items()):
if len(val) > 1 and (val.startswith('"') and val.endswith('"')
or val.startswith('"') and val.endswith('"')):
emacs_vars[var] = val[1:-1]
return emacs_vars
def _detab_line(self, line: str) -> str:
r"""Recusively convert tabs to spaces in a single line.
Called from _detab()."""
if '\t' not in line:
return line
chunk1, chunk2 = line.split('\t', 1)
chunk1 += (' ' * (self.tab_width - len(chunk1) % self.tab_width))
output = chunk1 + chunk2
return self._detab_line(output)
def _detab(self, text: str) -> str:
r"""Iterate text line by line and convert tabs to spaces.
>>> m = Markdown()
>>> m._detab("\tfoo")
' foo'
>>> m._detab(" \tfoo")
' foo'
>>> m._detab("\t foo")
' foo'
>>> m._detab(" foo")
' foo'
>>> m._detab(" foo\n\tbar\tblam")
' foo\n bar blam'
"""
if '\t' not in text:
return text
output = []
for line in text.splitlines():
output.append(self._detab_line(line))
return '\n'.join(output)
# I broke out the html5 tags here and add them to _block_tags_a and
# _block_tags_b. This way html5 tags are easy to keep track of.
_html5tags = '|article|aside|header|hgroup|footer|nav|section|figure|figcaption'
_block_tags_a = 'p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|script|noscript|form|fieldset|iframe|math|ins|del|style|html|head|body'
_block_tags_a += _html5tags
_strict_tag_block_re = re.compile(r"""
( # save in \1
^ # start of line (with re.M)
<(%s) # start tag = \2
\b # word break
(.*\n)*? # any number of lines, minimally matching
</\2> # the matching end tag
[ \t]* # trailing spaces/tabs
(?=\n+|\Z) # followed by a newline or end of document
)
""" % _block_tags_a,
re.X | re.M)
_block_tags_b = 'p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|script|noscript|form|fieldset|iframe|math'
_block_tags_b += _html5tags
_span_tags = (
'a|abbr|acronym|b|bdo|big|br|button|cite|code|dfn|em|i|img|input|kbd|label|map|object|output|q'
'|samp|script|select|small|span|strong|sub|sup|textarea|time|tt|var'
)
_liberal_tag_block_re = re.compile(r"""
( # save in \1
^ # start of line (with re.M)
<(%s) # start tag = \2
\b # word break
(.*\n)*? # any number of lines, minimally matching
.*</\2> # the matching end tag
[ \t]* # trailing spaces/tabs
(?=\n+|\Z) # followed by a newline or end of document
)
""" % _block_tags_b,
re.X | re.M)
_html_markdown_attr_re = re.compile(
r'''\s+markdown=("1"|'1')''')
def _hash_html_block_sub(
self,
match: Union[re.Match, str],
raw: bool = False
) -> str:
if isinstance(match, str):
html = match
tag = None
else:
html = match.group(1)
try:
tag = match.group(2)
except IndexError:
tag = None
if not tag:
m = re.match(r'.*?<(\S).*?\s*>', html)
# tag shouldn't be none but make the assertion for type checker
assert m is not None
tag = m.group(1)
if raw and self.safe_mode:
html = self._sanitize_html(html)
elif 'markdown-in-html' in self.extras and 'markdown=' in html:
first_line = html.split('\n', 1)[0]
m = self._html_markdown_attr_re.search(first_line)
if m:
lines = html.split('\n')
# if MD is on same line as opening tag then split across two lines
lines = list(filter(None, (re.split(r'(.*?<%s.*markdown=.*?>)' % tag, lines[0])))) + lines[1:]
# if MD on same line as closing tag, split across two lines
lines = lines[:-1] + list(filter(None, re.split(r'(\s*?</%s>.*?$)' % tag, lines[-1])))
# extract key sections of the match
first_line = lines[0]
middle = '\n'.join(lines[1:-1])
last_line = lines[-1]
# remove `markdown="1"` attr from tag
first_line = first_line[:m.start()] + first_line[m.end():]
# hash the HTML segments to protect them
f_key = _hash_text(first_line)
self.html_blocks[f_key] = first_line
l_key = _hash_text(last_line)
self.html_blocks[l_key] = last_line
return ''.join(["\n\n", f_key,
"\n\n", middle, "\n\n",
l_key, "\n\n"])
elif self.extras.get('header-ids', {}).get('mixed') and self._h_tag_re.match(html):
html = self._h_tag_re.sub(self._h_tag_sub, html)
key = _hash_text(html)
self.html_blocks[key] = html
return "\n\n" + key + "\n\n"
@mark_stage(Stage.HASH_HTML)
def _hash_html_blocks(self, text: str, raw: bool = False) -> str:
"""Hashify HTML blocks
We only want to do this for block-level HTML tags, such as headers,
lists, and tables. That's because we still want to wrap <p>s around
"paragraphs" that are wrapped in non-block-level tags, such as anchors,
phrase emphasis, and spans. The list of tags we're looking for is
hard-coded.
@param raw {boolean} indicates if these are raw HTML blocks in
the original source. It makes a difference in "safe" mode.
"""
if '<' not in text:
return text
# Pass `raw` value into our calls to self._hash_html_block_sub.
hash_html_block_sub = _curry(self._hash_html_block_sub, raw=raw)
# First, look for nested blocks, e.g.:
# <div>
# <div>
# tags for inner block must be indented.
# </div>
# </div>
#
# The outermost tags must start at the left margin for this to match, and
# the inner nested divs must be indented.
# We need to do this before the next, more liberal match, because the next
# match will start at the first `<div>` and stop at the first `</div>`.
text = self._strict_tag_block_sub(text, self._block_tags_a, hash_html_block_sub)
# Now match more liberally, simply from `\n<tag>` to `</tag>\n`
text = self._liberal_tag_block_re.sub(hash_html_block_sub, text)
# now do the same for spans that are acting like blocks
# eg: an anchor split over multiple lines for readability
text = self._strict_tag_block_sub(
text, self._span_tags,
# inline elements can't contain block level elements, so only span gamut is required
lambda t: hash_html_block_sub(self._run_span_gamut(t))
)
# Special case just for <hr />. It was easier to make a special
# case than to make the other regex more complicated.
if "<hr" in text:
_hr_tag_re = _hr_tag_re_from_tab_width(self.tab_width)