893 lines
29 KiB
Python
893 lines
29 KiB
Python
"""
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Python Markdown
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A Python implementation of John Gruber's Markdown.
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Documentation: https://python-markdown.github.io/
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GitHub: https://github.com/Python-Markdown/markdown/
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PyPI: https://pypi.org/project/Markdown/
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Started by Manfred Stienstra (http://www.dwerg.net/).
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Maintained for a few years by Yuri Takhteyev (http://www.freewisdom.org).
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Currently maintained by Waylan Limberg (https://github.com/waylan),
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Dmitry Shachnev (https://github.com/mitya57) and Isaac Muse (https://github.com/facelessuser).
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Copyright 2007-2018 The Python Markdown Project (v. 1.7 and later)
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Copyright 2004, 2005, 2006 Yuri Takhteyev (v. 0.2-1.6b)
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Copyright 2004 Manfred Stienstra (the original version)
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License: BSD (see LICENSE.md for details).
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INLINE PATTERNS
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=============================================================================
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Inline patterns such as *emphasis* are handled by means of auxiliary
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objects, one per pattern. Pattern objects must be instances of classes
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that extend markdown.Pattern. Each pattern object uses a single regular
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expression and needs support the following methods:
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pattern.getCompiledRegExp() # returns a regular expression
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pattern.handleMatch(m) # takes a match object and returns
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# an ElementTree element or just plain text
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All of python markdown's built-in patterns subclass from Pattern,
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but you can add additional patterns that don't.
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Also note that all the regular expressions used by inline must
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capture the whole block. For this reason, they all start with
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'^(.*)' and end with '(.*)!'. In case with built-in expression
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Pattern takes care of adding the "^(.*)" and "(.*)!".
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Finally, the order in which regular expressions are applied is very
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important - e.g. if we first replace http://.../ links with <a> tags
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and _then_ try to replace inline html, we would end up with a mess.
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So, we apply the expressions in the following order:
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* escape and backticks have to go before everything else, so
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that we can preempt any markdown patterns by escaping them.
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* then we handle auto-links (must be done before inline html)
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* then we handle inline HTML. At this point we will simply
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replace all inline HTML strings with a placeholder and add
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the actual HTML to a hash.
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* then inline images (must be done before links)
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* then bracketed links, first regular then reference-style
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* finally we apply strong and emphasis
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"""
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from . import util
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from collections import namedtuple
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import re
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import xml.etree.ElementTree as etree
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try: # pragma: no cover
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from html import entities
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except ImportError: # pragma: no cover
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import htmlentitydefs as entities
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def build_inlinepatterns(md, **kwargs):
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""" Build the default set of inline patterns for Markdown. """
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inlinePatterns = util.Registry()
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inlinePatterns.register(BacktickInlineProcessor(BACKTICK_RE), 'backtick', 190)
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inlinePatterns.register(EscapeInlineProcessor(ESCAPE_RE, md), 'escape', 180)
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inlinePatterns.register(ReferenceInlineProcessor(REFERENCE_RE, md), 'reference', 170)
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inlinePatterns.register(LinkInlineProcessor(LINK_RE, md), 'link', 160)
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inlinePatterns.register(ImageInlineProcessor(IMAGE_LINK_RE, md), 'image_link', 150)
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inlinePatterns.register(
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ImageReferenceInlineProcessor(IMAGE_REFERENCE_RE, md), 'image_reference', 140
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)
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inlinePatterns.register(
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ShortReferenceInlineProcessor(REFERENCE_RE, md), 'short_reference', 130
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)
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inlinePatterns.register(
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ShortImageReferenceInlineProcessor(IMAGE_REFERENCE_RE, md), 'short_image_ref', 125
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)
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inlinePatterns.register(AutolinkInlineProcessor(AUTOLINK_RE, md), 'autolink', 120)
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inlinePatterns.register(AutomailInlineProcessor(AUTOMAIL_RE, md), 'automail', 110)
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inlinePatterns.register(SubstituteTagInlineProcessor(LINE_BREAK_RE, 'br'), 'linebreak', 100)
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inlinePatterns.register(HtmlInlineProcessor(HTML_RE, md), 'html', 90)
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inlinePatterns.register(HtmlInlineProcessor(ENTITY_RE, md), 'entity', 80)
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inlinePatterns.register(SimpleTextInlineProcessor(NOT_STRONG_RE), 'not_strong', 70)
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inlinePatterns.register(AsteriskProcessor(r'\*'), 'em_strong', 60)
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inlinePatterns.register(UnderscoreProcessor(r'_'), 'em_strong2', 50)
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return inlinePatterns
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"""
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The actual regular expressions for patterns
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-----------------------------------------------------------------------------
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"""
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NOIMG = r'(?<!\!)'
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# `e=f()` or ``e=f("`")``
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BACKTICK_RE = r'(?:(?<!\\)((?:\\{2})+)(?=`+)|(?<!\\)(`+)(.+?)(?<!`)\2(?!`))'
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# \<
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ESCAPE_RE = r'\\(.)'
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# *emphasis*
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EMPHASIS_RE = r'(\*)([^\*]+)\1'
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# **strong**
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STRONG_RE = r'(\*{2})(.+?)\1'
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# __smart__strong__
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SMART_STRONG_RE = r'(?<!\w)(_{2})(?!_)(.+?)(?<!_)\1(?!\w)'
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# _smart_emphasis_
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SMART_EMPHASIS_RE = r'(?<!\w)(_)(?!_)(.+?)(?<!_)\1(?!\w)'
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# __strong _em__
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SMART_STRONG_EM_RE = r'(?<!\w)(\_)\1(?!\1)(.+?)(?<!\w)\1(?!\1)(.+?)\1{3}(?!\w)'
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# ***strongem*** or ***em*strong**
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EM_STRONG_RE = r'(\*)\1{2}(.+?)\1(.*?)\1{2}'
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# ___strongem___ or ___em_strong__
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EM_STRONG2_RE = r'(_)\1{2}(.+?)\1(.*?)\1{2}'
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# ***strong**em*
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STRONG_EM_RE = r'(\*)\1{2}(.+?)\1{2}(.*?)\1'
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# ___strong__em_
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STRONG_EM2_RE = r'(_)\1{2}(.+?)\1{2}(.*?)\1'
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# **strong*em***
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STRONG_EM3_RE = r'(\*)\1(?!\1)([^*]+?)\1(?!\1)(.+?)\1{3}'
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# [text](url) or [text](<url>) or [text](url "title")
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LINK_RE = NOIMG + r'\['
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#  or 
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IMAGE_LINK_RE = r'\!\['
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# [Google][3]
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REFERENCE_RE = LINK_RE
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# ![alt text][2]
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IMAGE_REFERENCE_RE = IMAGE_LINK_RE
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# stand-alone * or _
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NOT_STRONG_RE = r'((^|\s)(\*|_)(\s|$))'
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# <http://www.123.com>
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AUTOLINK_RE = r'<((?:[Ff]|[Hh][Tt])[Tt][Pp][Ss]?://[^<>]*)>'
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# <me@example.com>
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AUTOMAIL_RE = r'<([^<> !]*@[^@<> ]*)>'
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# <...>
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HTML_RE = r'(<([a-zA-Z/][^<>]*|!--(?:(?!<!--|-->).)*--)>)'
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# "&" (decimal) or "&" (hex) or "&" (named)
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ENTITY_RE = r'(&(?:\#[0-9]+|\#x[0-9a-fA-F]+|[a-zA-Z0-9]+);)'
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# two spaces at end of line
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LINE_BREAK_RE = r' \n'
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def dequote(string):
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"""Remove quotes from around a string."""
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if ((string.startswith('"') and string.endswith('"')) or
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(string.startswith("'") and string.endswith("'"))):
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return string[1:-1]
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else:
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return string
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class EmStrongItem(namedtuple('EmStrongItem', ['pattern', 'builder', 'tags'])):
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"""Emphasis/strong pattern item."""
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"""
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The pattern classes
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-----------------------------------------------------------------------------
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"""
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class Pattern: # pragma: no cover
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"""Base class that inline patterns subclass. """
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ANCESTOR_EXCLUDES = tuple()
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def __init__(self, pattern, md=None):
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"""
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Create an instant of an inline pattern.
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Keyword arguments:
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* pattern: A regular expression that matches a pattern
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"""
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self.pattern = pattern
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self.compiled_re = re.compile(r"^(.*?)%s(.*)$" % pattern,
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re.DOTALL | re.UNICODE)
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self.md = md
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@property
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@util.deprecated("Use 'md' instead.")
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def markdown(self):
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# TODO: remove this later
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return self.md
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def getCompiledRegExp(self):
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""" Return a compiled regular expression. """
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return self.compiled_re
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def handleMatch(self, m):
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"""Return a ElementTree element from the given match.
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Subclasses should override this method.
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Keyword arguments:
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* m: A re match object containing a match of the pattern.
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"""
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pass # pragma: no cover
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def type(self):
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""" Return class name, to define pattern type """
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return self.__class__.__name__
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def unescape(self, text):
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""" Return unescaped text given text with an inline placeholder. """
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try:
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stash = self.md.treeprocessors['inline'].stashed_nodes
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except KeyError: # pragma: no cover
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return text
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def get_stash(m):
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id = m.group(1)
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if id in stash:
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value = stash.get(id)
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if isinstance(value, str):
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return value
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else:
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# An etree Element - return text content only
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return ''.join(value.itertext())
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return util.INLINE_PLACEHOLDER_RE.sub(get_stash, text)
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class InlineProcessor(Pattern):
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"""
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Base class that inline patterns subclass.
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This is the newer style inline processor that uses a more
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efficient and flexible search approach.
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"""
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def __init__(self, pattern, md=None):
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"""
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Create an instant of an inline pattern.
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Keyword arguments:
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* pattern: A regular expression that matches a pattern
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"""
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self.pattern = pattern
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self.compiled_re = re.compile(pattern, re.DOTALL | re.UNICODE)
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# Api for Markdown to pass safe_mode into instance
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self.safe_mode = False
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self.md = md
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def handleMatch(self, m, data):
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"""Return a ElementTree element from the given match and the
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start and end index of the matched text.
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If `start` and/or `end` are returned as `None`, it will be
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assumed that the processor did not find a valid region of text.
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Subclasses should override this method.
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Keyword arguments:
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* m: A re match object containing a match of the pattern.
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* data: The buffer current under analysis
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Returns:
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* el: The ElementTree element, text or None.
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* start: The start of the region that has been matched or None.
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* end: The end of the region that has been matched or None.
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"""
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pass # pragma: no cover
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class SimpleTextPattern(Pattern): # pragma: no cover
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""" Return a simple text of group(2) of a Pattern. """
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def handleMatch(self, m):
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return m.group(2)
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class SimpleTextInlineProcessor(InlineProcessor):
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""" Return a simple text of group(1) of a Pattern. """
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def handleMatch(self, m, data):
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return m.group(1), m.start(0), m.end(0)
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class EscapeInlineProcessor(InlineProcessor):
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""" Return an escaped character. """
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def handleMatch(self, m, data):
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char = m.group(1)
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if char in self.md.ESCAPED_CHARS:
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return '{}{}{}'.format(util.STX, ord(char), util.ETX), m.start(0), m.end(0)
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else:
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return None, m.start(0), m.end(0)
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class SimpleTagPattern(Pattern): # pragma: no cover
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"""
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Return element of type `tag` with a text attribute of group(3)
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of a Pattern.
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"""
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def __init__(self, pattern, tag):
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Pattern.__init__(self, pattern)
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self.tag = tag
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def handleMatch(self, m):
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el = etree.Element(self.tag)
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el.text = m.group(3)
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return el
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class SimpleTagInlineProcessor(InlineProcessor):
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"""
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Return element of type `tag` with a text attribute of group(2)
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of a Pattern.
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"""
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def __init__(self, pattern, tag):
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InlineProcessor.__init__(self, pattern)
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self.tag = tag
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def handleMatch(self, m, data): # pragma: no cover
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el = etree.Element(self.tag)
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el.text = m.group(2)
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return el, m.start(0), m.end(0)
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class SubstituteTagPattern(SimpleTagPattern): # pragma: no cover
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""" Return an element of type `tag` with no children. """
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def handleMatch(self, m):
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return etree.Element(self.tag)
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class SubstituteTagInlineProcessor(SimpleTagInlineProcessor):
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""" Return an element of type `tag` with no children. """
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def handleMatch(self, m, data):
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return etree.Element(self.tag), m.start(0), m.end(0)
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class BacktickInlineProcessor(InlineProcessor):
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""" Return a `<code>` element containing the matching text. """
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def __init__(self, pattern):
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InlineProcessor.__init__(self, pattern)
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self.ESCAPED_BSLASH = '{}{}{}'.format(util.STX, ord('\\'), util.ETX)
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self.tag = 'code'
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def handleMatch(self, m, data):
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if m.group(3):
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el = etree.Element(self.tag)
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el.text = util.AtomicString(util.code_escape(m.group(3).strip()))
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return el, m.start(0), m.end(0)
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else:
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return m.group(1).replace('\\\\', self.ESCAPED_BSLASH), m.start(0), m.end(0)
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class DoubleTagPattern(SimpleTagPattern): # pragma: no cover
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"""Return a ElementTree element nested in tag2 nested in tag1.
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Useful for strong emphasis etc.
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"""
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def handleMatch(self, m):
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tag1, tag2 = self.tag.split(",")
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el1 = etree.Element(tag1)
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el2 = etree.SubElement(el1, tag2)
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el2.text = m.group(3)
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if len(m.groups()) == 5:
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el2.tail = m.group(4)
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return el1
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class DoubleTagInlineProcessor(SimpleTagInlineProcessor):
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"""Return a ElementTree element nested in tag2 nested in tag1.
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Useful for strong emphasis etc.
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"""
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def handleMatch(self, m, data): # pragma: no cover
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tag1, tag2 = self.tag.split(",")
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el1 = etree.Element(tag1)
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el2 = etree.SubElement(el1, tag2)
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el2.text = m.group(2)
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if len(m.groups()) == 3:
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el2.tail = m.group(3)
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return el1, m.start(0), m.end(0)
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class HtmlInlineProcessor(InlineProcessor):
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""" Store raw inline html and return a placeholder. """
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def handleMatch(self, m, data):
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rawhtml = self.unescape(m.group(1))
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place_holder = self.md.htmlStash.store(rawhtml)
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return place_holder, m.start(0), m.end(0)
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def unescape(self, text):
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""" Return unescaped text given text with an inline placeholder. """
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try:
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stash = self.md.treeprocessors['inline'].stashed_nodes
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except KeyError: # pragma: no cover
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return text
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def get_stash(m):
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id = m.group(1)
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value = stash.get(id)
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if value is not None:
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try:
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return self.md.serializer(value)
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except Exception:
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return r'\%s' % value
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return util.INLINE_PLACEHOLDER_RE.sub(get_stash, text)
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class AsteriskProcessor(InlineProcessor):
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"""Emphasis processor for handling strong and em matches inside asterisks."""
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PATTERNS = [
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EmStrongItem(re.compile(EM_STRONG_RE, re.DOTALL | re.UNICODE), 'double', 'strong,em'),
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EmStrongItem(re.compile(STRONG_EM_RE, re.DOTALL | re.UNICODE), 'double', 'em,strong'),
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EmStrongItem(re.compile(STRONG_EM3_RE, re.DOTALL | re.UNICODE), 'double2', 'strong,em'),
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EmStrongItem(re.compile(STRONG_RE, re.DOTALL | re.UNICODE), 'single', 'strong'),
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EmStrongItem(re.compile(EMPHASIS_RE, re.DOTALL | re.UNICODE), 'single', 'em')
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]
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def build_single(self, m, tag, idx):
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"""Return single tag."""
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el1 = etree.Element(tag)
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text = m.group(2)
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self.parse_sub_patterns(text, el1, None, idx)
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return el1
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def build_double(self, m, tags, idx):
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"""Return double tag."""
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tag1, tag2 = tags.split(",")
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el1 = etree.Element(tag1)
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el2 = etree.Element(tag2)
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text = m.group(2)
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self.parse_sub_patterns(text, el2, None, idx)
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el1.append(el2)
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if len(m.groups()) == 3:
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text = m.group(3)
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self.parse_sub_patterns(text, el1, el2, idx)
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return el1
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def build_double2(self, m, tags, idx):
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"""Return double tags (variant 2): `<strong>text <em>text</em></strong>`."""
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tag1, tag2 = tags.split(",")
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el1 = etree.Element(tag1)
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el2 = etree.Element(tag2)
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text = m.group(2)
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self.parse_sub_patterns(text, el1, None, idx)
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text = m.group(3)
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el1.append(el2)
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self.parse_sub_patterns(text, el2, None, idx)
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return el1
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def parse_sub_patterns(self, data, parent, last, idx):
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"""
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Parses sub patterns.
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`data` (`str`):
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text to evaluate.
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`parent` (`etree.Element`):
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Parent to attach text and sub elements to.
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`last` (`etree.Element`):
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Last appended child to parent. Can also be None if parent has no children.
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`idx` (`int`):
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Current pattern index that was used to evaluate the parent.
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"""
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offset = 0
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pos = 0
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|
|
|
length = len(data)
|
|
while pos < length:
|
|
# Find the start of potential emphasis or strong tokens
|
|
if self.compiled_re.match(data, pos):
|
|
matched = False
|
|
# See if the we can match an emphasis/strong pattern
|
|
for index, item in enumerate(self.PATTERNS):
|
|
# Only evaluate patterns that are after what was used on the parent
|
|
if index <= idx:
|
|
continue
|
|
m = item.pattern.match(data, pos)
|
|
if m:
|
|
# Append child nodes to parent
|
|
# Text nodes should be appended to the last
|
|
# child if present, and if not, it should
|
|
# be added as the parent's text node.
|
|
text = data[offset:m.start(0)]
|
|
if text:
|
|
if last is not None:
|
|
last.tail = text
|
|
else:
|
|
parent.text = text
|
|
el = self.build_element(m, item.builder, item.tags, index)
|
|
parent.append(el)
|
|
last = el
|
|
# Move our position past the matched hunk
|
|
offset = pos = m.end(0)
|
|
matched = True
|
|
if not matched:
|
|
# We matched nothing, move on to the next character
|
|
pos += 1
|
|
else:
|
|
# Increment position as no potential emphasis start was found.
|
|
pos += 1
|
|
|
|
# Append any leftover text as a text node.
|
|
text = data[offset:]
|
|
if text:
|
|
if last is not None:
|
|
last.tail = text
|
|
else:
|
|
parent.text = text
|
|
|
|
def build_element(self, m, builder, tags, index):
|
|
"""Element builder."""
|
|
|
|
if builder == 'double2':
|
|
return self.build_double2(m, tags, index)
|
|
elif builder == 'double':
|
|
return self.build_double(m, tags, index)
|
|
else:
|
|
return self.build_single(m, tags, index)
|
|
|
|
def handleMatch(self, m, data):
|
|
"""Parse patterns."""
|
|
|
|
el = None
|
|
start = None
|
|
end = None
|
|
|
|
for index, item in enumerate(self.PATTERNS):
|
|
m1 = item.pattern.match(data, m.start(0))
|
|
if m1:
|
|
start = m1.start(0)
|
|
end = m1.end(0)
|
|
el = self.build_element(m1, item.builder, item.tags, index)
|
|
break
|
|
return el, start, end
|
|
|
|
|
|
class UnderscoreProcessor(AsteriskProcessor):
|
|
"""Emphasis processor for handling strong and em matches inside underscores."""
|
|
|
|
PATTERNS = [
|
|
EmStrongItem(re.compile(EM_STRONG2_RE, re.DOTALL | re.UNICODE), 'double', 'strong,em'),
|
|
EmStrongItem(re.compile(STRONG_EM2_RE, re.DOTALL | re.UNICODE), 'double', 'em,strong'),
|
|
EmStrongItem(re.compile(SMART_STRONG_EM_RE, re.DOTALL | re.UNICODE), 'double2', 'strong,em'),
|
|
EmStrongItem(re.compile(SMART_STRONG_RE, re.DOTALL | re.UNICODE), 'single', 'strong'),
|
|
EmStrongItem(re.compile(SMART_EMPHASIS_RE, re.DOTALL | re.UNICODE), 'single', 'em')
|
|
]
|
|
|
|
|
|
class LinkInlineProcessor(InlineProcessor):
|
|
""" Return a link element from the given match. """
|
|
RE_LINK = re.compile(r'''\(\s*(?:(<[^<>]*>)\s*(?:('[^']*'|"[^"]*")\s*)?\))?''', re.DOTALL | re.UNICODE)
|
|
RE_TITLE_CLEAN = re.compile(r'\s')
|
|
|
|
def handleMatch(self, m, data):
|
|
text, index, handled = self.getText(data, m.end(0))
|
|
|
|
if not handled:
|
|
return None, None, None
|
|
|
|
href, title, index, handled = self.getLink(data, index)
|
|
if not handled:
|
|
return None, None, None
|
|
|
|
el = etree.Element("a")
|
|
el.text = text
|
|
|
|
el.set("href", href)
|
|
|
|
if title is not None:
|
|
el.set("title", title)
|
|
|
|
return el, m.start(0), index
|
|
|
|
def getLink(self, data, index):
|
|
"""Parse data between `()` of `[Text]()` allowing recursive `()`. """
|
|
|
|
href = ''
|
|
title = None
|
|
handled = False
|
|
|
|
m = self.RE_LINK.match(data, pos=index)
|
|
if m and m.group(1):
|
|
# Matches [Text](<link> "title")
|
|
href = m.group(1)[1:-1].strip()
|
|
if m.group(2):
|
|
title = m.group(2)[1:-1]
|
|
index = m.end(0)
|
|
handled = True
|
|
elif m:
|
|
# Track bracket nesting and index in string
|
|
bracket_count = 1
|
|
backtrack_count = 1
|
|
start_index = m.end()
|
|
index = start_index
|
|
last_bracket = -1
|
|
|
|
# Primary (first found) quote tracking.
|
|
quote = None
|
|
start_quote = -1
|
|
exit_quote = -1
|
|
ignore_matches = False
|
|
|
|
# Secondary (second found) quote tracking.
|
|
alt_quote = None
|
|
start_alt_quote = -1
|
|
exit_alt_quote = -1
|
|
|
|
# Track last character
|
|
last = ''
|
|
|
|
for pos in range(index, len(data)):
|
|
c = data[pos]
|
|
if c == '(':
|
|
# Count nested (
|
|
# Don't increment the bracket count if we are sure we're in a title.
|
|
if not ignore_matches:
|
|
bracket_count += 1
|
|
elif backtrack_count > 0:
|
|
backtrack_count -= 1
|
|
elif c == ')':
|
|
# Match nested ) to (
|
|
# Don't decrement if we are sure we are in a title that is unclosed.
|
|
if ((exit_quote != -1 and quote == last) or (exit_alt_quote != -1 and alt_quote == last)):
|
|
bracket_count = 0
|
|
elif not ignore_matches:
|
|
bracket_count -= 1
|
|
elif backtrack_count > 0:
|
|
backtrack_count -= 1
|
|
# We've found our backup end location if the title doesn't reslove.
|
|
if backtrack_count == 0:
|
|
last_bracket = index + 1
|
|
|
|
elif c in ("'", '"'):
|
|
# Quote has started
|
|
if not quote:
|
|
# We'll assume we are now in a title.
|
|
# Brackets are quoted, so no need to match them (except for the final one).
|
|
ignore_matches = True
|
|
backtrack_count = bracket_count
|
|
bracket_count = 1
|
|
start_quote = index + 1
|
|
quote = c
|
|
# Secondary quote (in case the first doesn't resolve): [text](link'"title")
|
|
elif c != quote and not alt_quote:
|
|
start_alt_quote = index + 1
|
|
alt_quote = c
|
|
# Update primary quote match
|
|
elif c == quote:
|
|
exit_quote = index + 1
|
|
# Update secondary quote match
|
|
elif alt_quote and c == alt_quote:
|
|
exit_alt_quote = index + 1
|
|
|
|
index += 1
|
|
|
|
# Link is closed, so let's break out of the loop
|
|
if bracket_count == 0:
|
|
# Get the title if we closed a title string right before link closed
|
|
if exit_quote >= 0 and quote == last:
|
|
href = data[start_index:start_quote - 1]
|
|
title = ''.join(data[start_quote:exit_quote - 1])
|
|
elif exit_alt_quote >= 0 and alt_quote == last:
|
|
href = data[start_index:start_alt_quote - 1]
|
|
title = ''.join(data[start_alt_quote:exit_alt_quote - 1])
|
|
else:
|
|
href = data[start_index:index - 1]
|
|
break
|
|
|
|
if c != ' ':
|
|
last = c
|
|
|
|
# We have a scenario: [test](link"notitle)
|
|
# When we enter a string, we stop tracking bracket resolution in the main counter,
|
|
# but we do keep a backup counter up until we discover where we might resolve all brackets
|
|
# if the title string fails to resolve.
|
|
if bracket_count != 0 and backtrack_count == 0:
|
|
href = data[start_index:last_bracket - 1]
|
|
index = last_bracket
|
|
bracket_count = 0
|
|
|
|
handled = bracket_count == 0
|
|
|
|
if title is not None:
|
|
title = self.RE_TITLE_CLEAN.sub(' ', dequote(self.unescape(title.strip())))
|
|
|
|
href = self.unescape(href).strip()
|
|
|
|
return href, title, index, handled
|
|
|
|
def getText(self, data, index):
|
|
"""Parse the content between `[]` of the start of an image or link
|
|
resolving nested square brackets.
|
|
|
|
"""
|
|
bracket_count = 1
|
|
text = []
|
|
for pos in range(index, len(data)):
|
|
c = data[pos]
|
|
if c == ']':
|
|
bracket_count -= 1
|
|
elif c == '[':
|
|
bracket_count += 1
|
|
index += 1
|
|
if bracket_count == 0:
|
|
break
|
|
text.append(c)
|
|
return ''.join(text), index, bracket_count == 0
|
|
|
|
|
|
class ImageInlineProcessor(LinkInlineProcessor):
|
|
""" Return a img element from the given match. """
|
|
|
|
def handleMatch(self, m, data):
|
|
text, index, handled = self.getText(data, m.end(0))
|
|
if not handled:
|
|
return None, None, None
|
|
|
|
src, title, index, handled = self.getLink(data, index)
|
|
if not handled:
|
|
return None, None, None
|
|
|
|
el = etree.Element("img")
|
|
|
|
el.set("src", src)
|
|
|
|
if title is not None:
|
|
el.set("title", title)
|
|
|
|
el.set('alt', self.unescape(text))
|
|
return el, m.start(0), index
|
|
|
|
|
|
class ReferenceInlineProcessor(LinkInlineProcessor):
|
|
""" Match to a stored reference and return link element. """
|
|
NEWLINE_CLEANUP_RE = re.compile(r'\s+', re.MULTILINE)
|
|
|
|
RE_LINK = re.compile(r'\s?\[([^\]]*)\]', re.DOTALL | re.UNICODE)
|
|
|
|
def handleMatch(self, m, data):
|
|
text, index, handled = self.getText(data, m.end(0))
|
|
if not handled:
|
|
return None, None, None
|
|
|
|
id, end, handled = self.evalId(data, index, text)
|
|
if not handled:
|
|
return None, None, None
|
|
|
|
# Clean up linebreaks in id
|
|
id = self.NEWLINE_CLEANUP_RE.sub(' ', id)
|
|
if id not in self.md.references: # ignore undefined refs
|
|
return None, m.start(0), end
|
|
|
|
href, title = self.md.references[id]
|
|
|
|
return self.makeTag(href, title, text), m.start(0), end
|
|
|
|
def evalId(self, data, index, text):
|
|
"""
|
|
Evaluate the id portion of [ref][id].
|
|
|
|
If [ref][] use [ref].
|
|
"""
|
|
m = self.RE_LINK.match(data, pos=index)
|
|
if not m:
|
|
return None, index, False
|
|
else:
|
|
id = m.group(1).lower()
|
|
end = m.end(0)
|
|
if not id:
|
|
id = text.lower()
|
|
return id, end, True
|
|
|
|
def makeTag(self, href, title, text):
|
|
el = etree.Element('a')
|
|
|
|
el.set('href', href)
|
|
if title:
|
|
el.set('title', title)
|
|
|
|
el.text = text
|
|
return el
|
|
|
|
|
|
class ShortReferenceInlineProcessor(ReferenceInlineProcessor):
|
|
"""Shorte form of reference: [google]. """
|
|
def evalId(self, data, index, text):
|
|
"""Evaluate the id from of [ref] """
|
|
|
|
return text.lower(), index, True
|
|
|
|
|
|
class ImageReferenceInlineProcessor(ReferenceInlineProcessor):
|
|
""" Match to a stored reference and return img element. """
|
|
def makeTag(self, href, title, text):
|
|
el = etree.Element("img")
|
|
el.set("src", href)
|
|
if title:
|
|
el.set("title", title)
|
|
el.set("alt", self.unescape(text))
|
|
return el
|
|
|
|
|
|
class ShortImageReferenceInlineProcessor(ImageReferenceInlineProcessor):
|
|
""" Short form of inage reference: ![ref]. """
|
|
def evalId(self, data, index, text):
|
|
"""Evaluate the id from of [ref] """
|
|
|
|
return text.lower(), index, True
|
|
|
|
|
|
class AutolinkInlineProcessor(InlineProcessor):
|
|
""" Return a link Element given an autolink (`<http://example/com>`). """
|
|
def handleMatch(self, m, data):
|
|
el = etree.Element("a")
|
|
el.set('href', self.unescape(m.group(1)))
|
|
el.text = util.AtomicString(m.group(1))
|
|
return el, m.start(0), m.end(0)
|
|
|
|
|
|
class AutomailInlineProcessor(InlineProcessor):
|
|
"""
|
|
Return a mailto link Element given an automail link (`<foo@example.com>`).
|
|
"""
|
|
def handleMatch(self, m, data):
|
|
el = etree.Element('a')
|
|
email = self.unescape(m.group(1))
|
|
if email.startswith("mailto:"):
|
|
email = email[len("mailto:"):]
|
|
|
|
def codepoint2name(code):
|
|
"""Return entity definition by code, or the code if not defined."""
|
|
entity = entities.codepoint2name.get(code)
|
|
if entity:
|
|
return "{}{};".format(util.AMP_SUBSTITUTE, entity)
|
|
else:
|
|
return "%s#%d;" % (util.AMP_SUBSTITUTE, code)
|
|
|
|
letters = [codepoint2name(ord(letter)) for letter in email]
|
|
el.text = util.AtomicString(''.join(letters))
|
|
|
|
mailto = "mailto:" + email
|
|
mailto = "".join([util.AMP_SUBSTITUTE + '#%d;' %
|
|
ord(letter) for letter in mailto])
|
|
el.set('href', mailto)
|
|
return el, m.start(0), m.end(0)
|