mwparserfromhell/src/mwparserfromhell/definitions.py

# Copyright (C) 2012-2020 Ben Kurtovic <ben.kurtovic@gmail.com>
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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# SOFTWARE.

"""
Contains data about certain markup, like HTML tags and external links.

When updating this file, please also update the the C tokenizer version:
- mwparserfromhell/parser/ctokenizer/definitions.c
- mwparserfromhell/parser/ctokenizer/definitions.h
"""

__all__ = [
    "get_html_tag",
    "is_parsable",
    "is_visible",
    "is_single",
    "is_single_only",
    "is_scheme",
]

URI_SCHEMES = {
    # [wikimedia/mediawiki.git]/includes/DefaultSettings.php @ 5c660de5d0
    "bitcoin": False,
    "ftp": True,
    "ftps": True,
    "geo": False,
    "git": True,
    "gopher": True,
    "http": True,
    "https": True,
    "irc": True,
    "ircs": True,
    "magnet": False,
    "mailto": False,
    "mms": True,
    "news": False,
    "nntp": True,
    "redis": True,
    "sftp": True,
    "sip": False,
    "sips": False,
    "sms": False,
    "ssh": True,
    "svn": True,
    "tel": False,
    "telnet": True,
    "urn": False,
    "worldwind": True,
    "xmpp": False,
}

PARSER_BLACKLIST = [
    # https://www.mediawiki.org/wiki/Parser_extension_tags @ 2020-12-21
    "categorytree",
    "ce",
    "chem",
    "gallery",
    "graph",
    "hiero",
    "imagemap",
    "inputbox",
    "math",
    "nowiki",
    "pre",
    "score",
    "section",
    "source",
    "syntaxhighlight",
    "templatedata",
    "timeline",
]

INVISIBLE_TAGS = [
    # https://www.mediawiki.org/wiki/Parser_extension_tags @ 2020-12-21
    "categorytree",
    "gallery",
    "graph",
    "imagemap",
    "inputbox",
    "math",
    "score",
    "section",
    "templatedata",
    "timeline",
]

# [wikimedia/mediawiki.git]/includes/parser/Sanitizer.php @ 95e17ee645
SINGLE_ONLY = ["br", "wbr", "hr", "meta", "link", "img"]
SINGLE = SINGLE_ONLY + ["li", "dt", "dd", "th", "td", "tr"]

MARKUP_TO_HTML = {
    "#": "li",
    "*": "li",
    ";": "dt",
    ":": "dd",
}


def get_html_tag(markup):
    """Return the HTML tag associated with the given wiki-markup."""
    return MARKUP_TO_HTML[markup]


def is_parsable(tag):
    """Return if the given *tag*'s contents should be passed to the parser."""
    return tag.lower() not in PARSER_BLACKLIST


def is_visible(tag):
    """Return whether or not the given *tag* contains visible text."""
    return tag.lower() not in INVISIBLE_TAGS


def is_single(tag):
    """Return whether or not the given *tag* can exist without a close tag."""
    return tag.lower() in SINGLE


def is_single_only(tag):
    """Return whether or not the given *tag* must exist without a close tag."""
    return tag.lower() in SINGLE_ONLY


def is_scheme(scheme, slashes=True):
    """Return whether *scheme* is valid for external links."""
    scheme = scheme.lower()
    if slashes:
        return scheme in URI_SCHEMES
    return scheme in URI_SCHEMES and not URI_SCHEMES[scheme]