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990 lines
37 KiB
Python
990 lines
37 KiB
Python
# 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 2007-2023 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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"""
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In version 3.0, a new, more flexible inline processor was added, [`markdown.inlinepatterns.InlineProcessor`][]. The
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original inline patterns, which inherit from [`markdown.inlinepatterns.Pattern`][] or one of its children are still
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supported, though users are encouraged to migrate.
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The new `InlineProcessor` provides two major enhancements to `Patterns`:
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1. Inline Processors no longer need to match the entire block, so regular expressions no longer need to start with
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`r'^(.*?)'` and end with `r'(.*?)%'`. This runs faster. The returned [`Match`][re.Match] object will only contain
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what is explicitly matched in the pattern, and extension pattern groups now start with `m.group(1)`.
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2. The `handleMatch` method now takes an additional input called `data`, which is the entire block under analysis,
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not just what is matched with the specified pattern. The method now returns the element *and* the indexes relative
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to `data` that the return element is replacing (usually `m.start(0)` and `m.end(0)`). If the boundaries are
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returned as `None`, it is assumed that the match did not take place, and nothing will be altered in `data`.
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This allows handling of more complex constructs than regular expressions can handle, e.g., matching nested
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brackets, and explicit control of the span "consumed" by the processor.
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"""
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from __future__ import annotations
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from . import util
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from typing import TYPE_CHECKING, Any, Collection, NamedTuple
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import re
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import xml.etree.ElementTree as etree
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from html import entities
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if TYPE_CHECKING: # pragma: no cover
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from markdown import Markdown
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def build_inlinepatterns(md: Markdown, **kwargs: Any) -> util.Registry[InlineProcessor]:
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"""
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Build the default set of inline patterns for Markdown.
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The order in which processors and/or patterns are applied is very important - e.g. if we first replace
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`http://.../` links with `<a>` tags and _then_ try to replace inline HTML, we would end up with a mess. So, we
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apply the expressions in the following order:
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* backticks and escaped characters have to be handled before everything else so that we can preempt any markdown
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patterns by escaping them;
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* then we handle the various types of links (auto-links must be handled before inline HTML);
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* then we handle inline HTML. At this point we will simply replace all inline HTML strings with a placeholder
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and add the actual HTML to a stash;
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* finally we apply strong, emphasis, etc.
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"""
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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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# The actual regular expressions for patterns
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# -----------------------------------------------------------------------------
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NOIMG = r'(?<!\!)'
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""" Match not an image. Partial regular expression which matches if not preceded by `!`. """
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BACKTICK_RE = r'(?:(?<!\\)((?:\\{2})+)(?=`+)|(?<!\\)(`+)(.+?)(?<!`)\2(?!`))'
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""" Match backtick quoted string (`` `e=f()` `` or ``` ``e=f("`")`` ```). """
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ESCAPE_RE = r'\\(.)'
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""" Match a backslash escaped character (`\\<` or `\\*`). """
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EMPHASIS_RE = r'(\*)([^\*]+)\1'
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""" Match emphasis with an asterisk (`*emphasis*`). """
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STRONG_RE = r'(\*{2})(.+?)\1'
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""" Match strong with an asterisk (`**strong**`). """
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SMART_STRONG_RE = r'(?<!\w)(_{2})(?!_)(.+?)(?<!_)\1(?!\w)'
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""" Match strong with underscore while ignoring middle word underscores (`__smart__strong__`). """
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SMART_EMPHASIS_RE = r'(?<!\w)(_)(?!_)(.+?)(?<!_)\1(?!\w)'
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""" Match emphasis with underscore while ignoring middle word underscores (`_smart_emphasis_`). """
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SMART_STRONG_EM_RE = r'(?<!\w)(\_)\1(?!\1)(.+?)(?<!\w)\1(?!\1)(.+?)\1{3}(?!\w)'
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""" Match strong emphasis with underscores (`__strong _em__`). """
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EM_STRONG_RE = r'(\*)\1{2}(.+?)\1(.*?)\1{2}'
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""" Match emphasis strong with asterisk (`***strongem***` or `***em*strong**`). """
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EM_STRONG2_RE = r'(_)\1{2}(.+?)\1(.*?)\1{2}'
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""" Match emphasis strong with underscores (`___emstrong___` or `___em_strong__`). """
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STRONG_EM_RE = r'(\*)\1{2}(.+?)\1{2}(.*?)\1'
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""" Match strong emphasis with asterisk (`***strong**em*`). """
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STRONG_EM2_RE = r'(_)\1{2}(.+?)\1{2}(.*?)\1'
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""" Match strong emphasis with underscores (`___strong__em_`). """
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STRONG_EM3_RE = r'(\*)\1(?!\1)([^*]+?)\1(?!\1)(.+?)\1{3}'
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""" Match strong emphasis with asterisk (`**strong*em***`). """
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LINK_RE = NOIMG + r'\['
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""" Match start of in-line link (`[text](url)` or `[text](<url>)` or `[text](url "title")`). """
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IMAGE_LINK_RE = r'\!\['
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""" Match start of in-line image link (`` or ``). """
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REFERENCE_RE = LINK_RE
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""" Match start of reference link (`[Label][3]`). """
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IMAGE_REFERENCE_RE = IMAGE_LINK_RE
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""" Match start of image reference (`![alt text][2]`). """
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NOT_STRONG_RE = r'((^|(?<=\s))(\*{1,3}|_{1,3})(?=\s|$))'
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""" Match a stand-alone `*` or `_`. """
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AUTOLINK_RE = r'<((?:[Ff]|[Hh][Tt])[Tt][Pp][Ss]?://[^<>]*)>'
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""" Match an automatic link (`<http://www.example.com>`). """
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AUTOMAIL_RE = r'<([^<> !]+@[^@<> ]+)>'
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""" Match an automatic email link (`<me@example.com>`). """
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HTML_RE = r'(<(\/?[a-zA-Z][^<>@ ]*( [^<>]*)?|!--(?:(?!<!--|-->).)*--)>)'
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""" Match an HTML tag (`<...>`). """
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ENTITY_RE = r'(&(?:\#[0-9]+|\#x[0-9a-fA-F]+|[a-zA-Z0-9]+);)'
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""" Match an HTML entity (`&` (decimal) or `&` (hex) or `&` (named)). """
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LINE_BREAK_RE = r' \n'
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""" Match two spaces at end of line. """
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def dequote(string: str) -> str:
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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):
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"""Emphasis/strong pattern item."""
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pattern: re.Pattern[str]
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builder: str
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tags: str
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# The pattern classes
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# -----------------------------------------------------------------------------
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class Pattern: # pragma: no cover
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"""
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Base class that inline patterns subclass.
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Inline patterns are handled by means of `Pattern` subclasses, one per regular expression.
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Each pattern object uses a single regular expression and must support the following methods:
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[`getCompiledRegExp`][markdown.inlinepatterns.Pattern.getCompiledRegExp] and
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[`handleMatch`][markdown.inlinepatterns.Pattern.handleMatch].
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All the regular expressions used by `Pattern` subclasses must capture the whole block. For this
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reason, they all start with `^(.*)` and end with `(.*)!`. When passing a regular expression on
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class initialization, the `^(.*)` and `(.*)!` are added automatically and the regular expression
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is pre-compiled.
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It is strongly suggested that the newer style [`markdown.inlinepatterns.InlineProcessor`][] that
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use a more efficient and flexible search approach be used instead. However, the older style
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`Pattern` remains for backward compatibility with many existing third-party extensions.
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"""
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ANCESTOR_EXCLUDES: Collection[str] = tuple()
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"""
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A collection of elements which are undesirable ancestors. The processor will be skipped if it
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would cause the content to be a descendant of one of the listed tag names.
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"""
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compiled_re: re.Pattern[str]
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md: Markdown | None
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def __init__(self, pattern: str, md: Markdown | None = None):
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"""
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Create an instant of an inline pattern.
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Arguments:
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pattern: A regular expression that matches a pattern.
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md: An optional pointer to the instance of `markdown.Markdown` and is available as
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`self.md` on the class instance.
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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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def getCompiledRegExp(self) -> re.Pattern:
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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: re.Match[str]) -> etree.Element | str:
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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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Arguments:
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m: A match object containing a match of the pattern.
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Returns: An ElementTree Element object.
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"""
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pass # pragma: no cover
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def type(self) -> str:
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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: str) -> str:
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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 processors 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: str, md: Markdown | None = None):
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"""
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Create an instant of an inline processor.
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Arguments:
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pattern: A regular expression that matches a pattern.
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md: An optional pointer to the instance of `markdown.Markdown` and is available as
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`self.md` on the class instance.
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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: re.Match[str], data: str) -> tuple[etree.Element | str | None, int | None, int | None]:
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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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Arguments:
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m: A re match object containing a match of the pattern.
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data: The buffer currently 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: re.Match[str]) -> str:
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""" Return string content of `group(2)` of a matching pattern. """
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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: re.Match[str], data: str) -> tuple[str, int, int]:
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""" Return string content of `group(1)` of a matching pattern. """
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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: re.Match[str], data: str) -> tuple[str | None, int, int]:
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"""
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If the character matched by `group(1)` of a pattern is in [`ESCAPED_CHARS`][markdown.Markdown.ESCAPED_CHARS]
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then return the integer representing the character's Unicode code point (as returned by [`ord`][]) wrapped
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in [`util.STX`][markdown.util.STX] and [`util.ETX`][markdown.util.ETX].
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If the matched character is not in [`ESCAPED_CHARS`][markdown.Markdown.ESCAPED_CHARS], then return `None`.
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"""
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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: str, tag: str):
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"""
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Create an instant of an simple tag pattern.
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Arguments:
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pattern: A regular expression that matches a pattern.
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tag: Tag of element.
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"""
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Pattern.__init__(self, pattern)
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self.tag = tag
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""" The tag of the rendered element. """
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def handleMatch(self, m: re.Match[str]) -> etree.Element:
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"""
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Return [`Element`][xml.etree.ElementTree.Element] of type `tag` with the string in `group(3)` of a
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matching pattern as the Element's text.
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"""
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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: str, tag: str):
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"""
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Create an instant of an simple tag processor.
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Arguments:
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pattern: A regular expression that matches a pattern.
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tag: Tag of element.
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"""
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InlineProcessor.__init__(self, pattern)
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self.tag = tag
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""" The tag of the rendered element. """
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def handleMatch(self, m: re.Match[str], data: str) -> tuple[etree.Element, int, int]: # pragma: no cover
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"""
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Return [`Element`][xml.etree.ElementTree.Element] of type `tag` with the string in `group(2)` of a
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matching pattern as the Element's text.
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"""
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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: re.Match[str]) -> etree.Element:
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""" Return empty [`Element`][xml.etree.ElementTree.Element] of type `tag`. """
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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: re.Match[str], data: str) -> tuple[etree.Element, int, int]:
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""" Return empty [`Element`][xml.etree.ElementTree.Element] of type `tag`. """
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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 escaped matching text. """
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def __init__(self, pattern: str):
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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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""" The tag of the rendered element. """
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def handleMatch(self, m: re.Match[str], data: str) -> tuple[etree.Element | str, int, int]:
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"""
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If the match contains `group(3)` of a pattern, then return a `code`
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[`Element`][xml.etree.ElementTree.Element] which contains HTML escaped text (with
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[`code_escape`][markdown.util.code_escape]) as an [`AtomicString`][markdown.util.AtomicString].
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If the match does not contain `group(3)` then return the text of `group(1)` backslash escaped.
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"""
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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: re.Match[str]) -> etree.Element:
|
|
"""
|
|
Return [`Element`][xml.etree.ElementTree.Element] in following format:
|
|
`<tag1><tag2>group(3)</tag2>group(4)</tag2>` where `group(4)` is optional.
|
|
|
|
"""
|
|
tag1, tag2 = self.tag.split(",")
|
|
el1 = etree.Element(tag1)
|
|
el2 = etree.SubElement(el1, tag2)
|
|
el2.text = m.group(3)
|
|
if len(m.groups()) == 5:
|
|
el2.tail = m.group(4)
|
|
return el1
|
|
|
|
|
|
class DoubleTagInlineProcessor(SimpleTagInlineProcessor):
|
|
"""Return a ElementTree element nested in tag2 nested in tag1.
|
|
|
|
Useful for strong emphasis etc.
|
|
|
|
"""
|
|
def handleMatch(self, m: re.Match[str], data: str) -> tuple[etree.Element, int, int]: # pragma: no cover
|
|
"""
|
|
Return [`Element`][xml.etree.ElementTree.Element] in following format:
|
|
`<tag1><tag2>group(2)</tag2>group(3)</tag2>` where `group(3)` is optional.
|
|
|
|
"""
|
|
tag1, tag2 = self.tag.split(",")
|
|
el1 = etree.Element(tag1)
|
|
el2 = etree.SubElement(el1, tag2)
|
|
el2.text = m.group(2)
|
|
if len(m.groups()) == 3:
|
|
el2.tail = m.group(3)
|
|
return el1, m.start(0), m.end(0)
|
|
|
|
|
|
class HtmlInlineProcessor(InlineProcessor):
|
|
""" Store raw inline html and return a placeholder. """
|
|
def handleMatch(self, m: re.Match[str], data: str) -> tuple[str, int, int]:
|
|
""" Store the text of `group(1)` of a pattern and return a placeholder string. """
|
|
rawhtml = self.backslash_unescape(self.unescape(m.group(1)))
|
|
place_holder = self.md.htmlStash.store(rawhtml)
|
|
return place_holder, m.start(0), m.end(0)
|
|
|
|
def unescape(self, text: str) -> str:
|
|
""" Return unescaped text given text with an inline placeholder. """
|
|
try:
|
|
stash = self.md.treeprocessors['inline'].stashed_nodes
|
|
except KeyError: # pragma: no cover
|
|
return text
|
|
|
|
def get_stash(m: re.Match[str]) -> str:
|
|
id = m.group(1)
|
|
value = stash.get(id)
|
|
if value is not None:
|
|
try:
|
|
return self.md.serializer(value)
|
|
except Exception:
|
|
return r'\%s' % value
|
|
|
|
return util.INLINE_PLACEHOLDER_RE.sub(get_stash, text)
|
|
|
|
def backslash_unescape(self, text: str) -> str:
|
|
""" Return text with backslash escapes undone (backslashes are restored). """
|
|
try:
|
|
RE = self.md.treeprocessors['unescape'].RE
|
|
except KeyError: # pragma: no cover
|
|
return text
|
|
|
|
def _unescape(m: re.Match[str]) -> str:
|
|
return chr(int(m.group(1)))
|
|
|
|
return RE.sub(_unescape, text)
|
|
|
|
|
|
class AsteriskProcessor(InlineProcessor):
|
|
"""Emphasis processor for handling strong and em matches inside asterisks."""
|
|
|
|
PATTERNS = [
|
|
EmStrongItem(re.compile(EM_STRONG_RE, re.DOTALL | re.UNICODE), 'double', 'strong,em'),
|
|
EmStrongItem(re.compile(STRONG_EM_RE, re.DOTALL | re.UNICODE), 'double', 'em,strong'),
|
|
EmStrongItem(re.compile(STRONG_EM3_RE, re.DOTALL | re.UNICODE), 'double2', 'strong,em'),
|
|
EmStrongItem(re.compile(STRONG_RE, re.DOTALL | re.UNICODE), 'single', 'strong'),
|
|
EmStrongItem(re.compile(EMPHASIS_RE, re.DOTALL | re.UNICODE), 'single', 'em')
|
|
]
|
|
""" The various strong and emphasis patterns handled by this processor. """
|
|
|
|
def build_single(self, m: re.Match[str], tag: str, idx: int) -> etree.Element:
|
|
"""Return single tag."""
|
|
el1 = etree.Element(tag)
|
|
text = m.group(2)
|
|
self.parse_sub_patterns(text, el1, None, idx)
|
|
return el1
|
|
|
|
def build_double(self, m: re.Match[str], tags: str, idx: int) -> etree.Element:
|
|
"""Return double tag."""
|
|
|
|
tag1, tag2 = tags.split(",")
|
|
el1 = etree.Element(tag1)
|
|
el2 = etree.Element(tag2)
|
|
text = m.group(2)
|
|
self.parse_sub_patterns(text, el2, None, idx)
|
|
el1.append(el2)
|
|
if len(m.groups()) == 3:
|
|
text = m.group(3)
|
|
self.parse_sub_patterns(text, el1, el2, idx)
|
|
return el1
|
|
|
|
def build_double2(self, m: re.Match[str], tags: str, idx: int) -> etree.Element:
|
|
"""Return double tags (variant 2): `<strong>text <em>text</em></strong>`."""
|
|
|
|
tag1, tag2 = tags.split(",")
|
|
el1 = etree.Element(tag1)
|
|
el2 = etree.Element(tag2)
|
|
text = m.group(2)
|
|
self.parse_sub_patterns(text, el1, None, idx)
|
|
text = m.group(3)
|
|
el1.append(el2)
|
|
self.parse_sub_patterns(text, el2, None, idx)
|
|
return el1
|
|
|
|
def parse_sub_patterns(
|
|
self, data: str, parent: etree.Element, last: etree.Element | None, idx: int
|
|
) -> None:
|
|
"""
|
|
Parses sub patterns.
|
|
|
|
`data`: text to evaluate.
|
|
|
|
`parent`: Parent to attach text and sub elements to.
|
|
|
|
`last`: Last appended child to parent. Can also be None if parent has no children.
|
|
|
|
`idx`: Current pattern index that was used to evaluate the parent.
|
|
"""
|
|
|
|
offset = 0
|
|
pos = 0
|
|
|
|
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: re.Match[str], builder: str, tags: str, index: int) -> etree.Element:
|
|
"""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: re.Match[str], data: str) -> tuple[etree.Element | None, int | None, int | None]:
|
|
"""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')
|
|
]
|
|
""" The various strong and emphasis patterns handled by this processor. """
|
|
|
|
|
|
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: re.Match[str], data: str) -> tuple[etree.Element | None, int | None, int | None]:
|
|
""" Return an `a` [`Element`][xml.etree.ElementTree.Element] or `(None, None, None)`. """
|
|
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: str, index: int) -> tuple[str, str | None, int, bool]:
|
|
"""Parse data between `()` of `[Text]()` allowing recursive `()`. """
|
|
|
|
href = ''
|
|
title: str | None = 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: str | None = 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 resolve.
|
|
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: str, index: int) -> tuple[str, int, bool]:
|
|
"""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: re.Match[str], data: str) -> tuple[etree.Element | None, int | None, int | None]:
|
|
""" Return an `img` [`Element`][xml.etree.ElementTree.Element] or `(None, None, None)`. """
|
|
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: re.Match[str], data: str) -> tuple[etree.Element | None, int | None, int | None]:
|
|
"""
|
|
Return [`Element`][xml.etree.ElementTree.Element] returned by `makeTag` method or `(None, None, None)`.
|
|
|
|
"""
|
|
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 line breaks 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: str, index: int, text: str) -> tuple[str | None, int, bool]:
|
|
"""
|
|
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: str, title: str, text: str) -> etree.Element:
|
|
""" Return an `a` [`Element`][xml.etree.ElementTree.Element]. """
|
|
el = etree.Element('a')
|
|
|
|
el.set('href', href)
|
|
if title:
|
|
el.set('title', title)
|
|
|
|
el.text = text
|
|
return el
|
|
|
|
|
|
class ShortReferenceInlineProcessor(ReferenceInlineProcessor):
|
|
"""Short form of reference: `[google]`. """
|
|
def evalId(self, data: str, index: int, text: str) -> tuple[str, int, bool]:
|
|
"""Evaluate the id of `[ref]`. """
|
|
|
|
return text.lower(), index, True
|
|
|
|
|
|
class ImageReferenceInlineProcessor(ReferenceInlineProcessor):
|
|
""" Match to a stored reference and return `img` element. """
|
|
def makeTag(self, href: str, title: str, text: str) -> etree.Element:
|
|
""" Return an `img` [`Element`][xml.etree.ElementTree.Element]. """
|
|
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 image reference: `![ref]`. """
|
|
def evalId(self, data: str, index: int, text: str) -> tuple[str, int, bool]:
|
|
"""Evaluate the id of `[ref]`. """
|
|
|
|
return text.lower(), index, True
|
|
|
|
|
|
class AutolinkInlineProcessor(InlineProcessor):
|
|
""" Return a link Element given an auto-link (`<http://example/com>`). """
|
|
def handleMatch(self, m: re.Match[str], data: str) -> tuple[etree.Element, int, int]:
|
|
""" Return an `a` [`Element`][xml.etree.ElementTree.Element] of `group(1)`. """
|
|
el = etree.Element("a")
|
|
el.set('href', self.unescape(m.group(1)))
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|
el.text = util.AtomicString(m.group(1))
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|
return el, m.start(0), m.end(0)
|
|
|
|
|
|
class AutomailInlineProcessor(InlineProcessor):
|
|
"""
|
|
Return a `mailto` link Element given an auto-mail link (`<foo@example.com>`).
|
|
"""
|
|
def handleMatch(self, m: re.Match[str], data: str) -> tuple[etree.Element, int, int]:
|
|
""" Return an [`Element`][xml.etree.ElementTree.Element] containing a `mailto` link of `group(1)`. """
|
|
el = etree.Element('a')
|
|
email = self.unescape(m.group(1))
|
|
if email.startswith("mailto:"):
|
|
email = email[len("mailto:"):]
|
|
|
|
def codepoint2name(code: int) -> str:
|
|
"""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)
|