CoCalc -- soupparser.py

GitHub Repository: hhhrrrttt222111/Dorkify
Path: blob/master/venv/Lib/site-packages/lxml/html/soupparser.py
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"""External interface to the BeautifulSoup HTML parser.
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"""
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__all__ = ["fromstring", "parse", "convert_tree"]
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import re
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from lxml import etree, html
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try:
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    from bs4 import (
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        BeautifulSoup, Tag, Comment, ProcessingInstruction, NavigableString,
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        Declaration, Doctype)
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    _DECLARATION_OR_DOCTYPE = (Declaration, Doctype)
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except ImportError:
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    from BeautifulSoup import (
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        BeautifulSoup, Tag, Comment, ProcessingInstruction, NavigableString,
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        Declaration)
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    _DECLARATION_OR_DOCTYPE = Declaration
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def fromstring(data, beautifulsoup=None, makeelement=None, **bsargs):
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    """Parse a string of HTML data into an Element tree using the
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    BeautifulSoup parser.
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    Returns the root ``<html>`` Element of the tree.
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    You can pass a different BeautifulSoup parser through the
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    `beautifulsoup` keyword, and a diffent Element factory function
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    through the `makeelement` keyword.  By default, the standard
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    ``BeautifulSoup`` class and the default factory of `lxml.html` are
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    used.
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    """
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    return _parse(data, beautifulsoup, makeelement, **bsargs)
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def parse(file, beautifulsoup=None, makeelement=None, **bsargs):
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    """Parse a file into an ElemenTree using the BeautifulSoup parser.
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    You can pass a different BeautifulSoup parser through the
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    `beautifulsoup` keyword, and a diffent Element factory function
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    through the `makeelement` keyword.  By default, the standard
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    ``BeautifulSoup`` class and the default factory of `lxml.html` are
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    used.
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    """
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    if not hasattr(file, 'read'):
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        file = open(file)
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    root = _parse(file, beautifulsoup, makeelement, **bsargs)
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    return etree.ElementTree(root)
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def convert_tree(beautiful_soup_tree, makeelement=None):
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    """Convert a BeautifulSoup tree to a list of Element trees.
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    Returns a list instead of a single root Element to support
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    HTML-like soup with more than one root element.
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    You can pass a different Element factory through the `makeelement`
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    keyword.
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    """
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    root = _convert_tree(beautiful_soup_tree, makeelement)
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    children = root.getchildren()
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    for child in children:
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        root.remove(child)
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    return children
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# helpers
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def _parse(source, beautifulsoup, makeelement, **bsargs):
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    if beautifulsoup is None:
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        beautifulsoup = BeautifulSoup
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    if hasattr(beautifulsoup, "HTML_ENTITIES"):  # bs3
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        if 'convertEntities' not in bsargs:
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            bsargs['convertEntities'] = 'html'
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    if hasattr(beautifulsoup, "DEFAULT_BUILDER_FEATURES"):  # bs4
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        if 'features' not in bsargs:
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            bsargs['features'] = 'html.parser'  # use Python html parser
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    tree = beautifulsoup(source, **bsargs)
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    root = _convert_tree(tree, makeelement)
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    # from ET: wrap the document in a html root element, if necessary
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    if len(root) == 1 and root[0].tag == "html":
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        return root[0]
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    root.tag = "html"
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    return root
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_parse_doctype_declaration = re.compile(
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    r'(?:\s|[<!])*DOCTYPE\s*HTML'
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    r'(?:\s+PUBLIC)?(?:\s+(\'[^\']*\'|"[^"]*"))?'
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    r'(?:\s+(\'[^\']*\'|"[^"]*"))?',
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    re.IGNORECASE).match
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class _PseudoTag:
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    # Minimal imitation of BeautifulSoup.Tag
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    def __init__(self, contents):
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        self.name = 'html'
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        self.attrs = []
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        self.contents = contents
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    def __iter__(self):
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        return self.contents.__iter__()
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def _convert_tree(beautiful_soup_tree, makeelement):
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    if makeelement is None:
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        makeelement = html.html_parser.makeelement
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    # Split the tree into three parts:
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    # i) everything before the root element: document type
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    # declaration, comments, processing instructions, whitespace
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    # ii) the root(s),
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    # iii) everything after the root: comments, processing
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    # instructions, whitespace
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    first_element_idx = last_element_idx = None
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    html_root = declaration = None
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    for i, e in enumerate(beautiful_soup_tree):
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        if isinstance(e, Tag):
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            if first_element_idx is None:
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                first_element_idx = i
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            last_element_idx = i
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            if html_root is None and e.name and e.name.lower() == 'html':
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                html_root = e
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        elif declaration is None and isinstance(e, _DECLARATION_OR_DOCTYPE):
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            declaration = e
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    # For a nice, well-formatted document, the variable roots below is
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    # a list consisting of a single <html> element. However, the document
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    # may be a soup like '<meta><head><title>Hello</head><body>Hi
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    # all<\p>'. In this example roots is a list containing meta, head
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    # and body elements.
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    if first_element_idx is None:
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        pre_root = post_root = []
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        roots = beautiful_soup_tree.contents
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    else:
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        pre_root = beautiful_soup_tree.contents[:first_element_idx]
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        roots = beautiful_soup_tree.contents[first_element_idx:last_element_idx+1]
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        post_root = beautiful_soup_tree.contents[last_element_idx+1:]
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    # Reorganize so that there is one <html> root...
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    if html_root is not None:
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        # ... use existing one if possible, ...
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        i = roots.index(html_root)
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        html_root.contents = roots[:i] + html_root.contents + roots[i+1:]
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    else:
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        # ... otherwise create a new one.
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        html_root = _PseudoTag(roots)
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    convert_node = _init_node_converters(makeelement)
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    # Process pre_root
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    res_root = convert_node(html_root)
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    prev = res_root
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    for e in reversed(pre_root):
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        converted = convert_node(e)
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        if converted is not None:
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            prev.addprevious(converted)
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            prev = converted
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    # ditto for post_root
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    prev = res_root
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    for e in post_root:
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        converted = convert_node(e)
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        if converted is not None:
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            prev.addnext(converted)
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            prev = converted
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    if declaration is not None:
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        try:
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            # bs4 provides full Doctype string
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            doctype_string = declaration.output_ready()
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        except AttributeError:
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            doctype_string = declaration.string
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        match = _parse_doctype_declaration(doctype_string)
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        if not match:
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            # Something is wrong if we end up in here. Since soupparser should
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            # tolerate errors, do not raise Exception, just let it pass.
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            pass
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        else:
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            external_id, sys_uri = match.groups()
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            docinfo = res_root.getroottree().docinfo
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            # strip quotes and update DOCTYPE values (any of None, '', '...')
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            docinfo.public_id = external_id and external_id[1:-1]
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            docinfo.system_url = sys_uri and sys_uri[1:-1]
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    return res_root
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def _init_node_converters(makeelement):
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    converters = {}
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    ordered_node_types = []
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    def converter(*types):
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        def add(handler):
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            for t in types:
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                converters[t] = handler
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                ordered_node_types.append(t)
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            return handler
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        return add
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    def find_best_converter(node):
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        for t in ordered_node_types:
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            if isinstance(node, t):
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                return converters[t]
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        return None
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    def convert_node(bs_node, parent=None):
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        # duplicated in convert_tag() below
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        try:
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            handler = converters[type(bs_node)]
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        except KeyError:
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            handler = converters[type(bs_node)] = find_best_converter(bs_node)
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        if handler is None:
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            return None
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        return handler(bs_node, parent)
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    def map_attrs(bs_attrs):
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        if isinstance(bs_attrs, dict):  # bs4
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            attribs = {}
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            for k, v in bs_attrs.items():
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                if isinstance(v, list):
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                    v = " ".join(v)
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                attribs[k] = unescape(v)
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        else:
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            attribs = dict((k, unescape(v)) for k, v in bs_attrs)
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        return attribs
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    def append_text(parent, text):
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        if len(parent) == 0:
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            parent.text = (parent.text or '') + text
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        else:
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            parent[-1].tail = (parent[-1].tail or '') + text
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    # converters are tried in order of their definition
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    @converter(Tag, _PseudoTag)
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    def convert_tag(bs_node, parent):
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        attrs = bs_node.attrs
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        if parent is not None:
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            attribs = map_attrs(attrs) if attrs else None
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            res = etree.SubElement(parent, bs_node.name, attrib=attribs)
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        else:
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            attribs = map_attrs(attrs) if attrs else {}
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            res = makeelement(bs_node.name, attrib=attribs)
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        for child in bs_node:
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            # avoid double recursion by inlining convert_node(), see above
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            try:
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                handler = converters[type(child)]
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            except KeyError:
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                pass
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            else:
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                if handler is not None:
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                    handler(child, res)
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                continue
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            convert_node(child, res)
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        return res
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    @converter(Comment)
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    def convert_comment(bs_node, parent):
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        res = html.HtmlComment(bs_node)
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        if parent is not None:
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            parent.append(res)
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        return res
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    @converter(ProcessingInstruction)
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    def convert_pi(bs_node, parent):
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        if bs_node.endswith('?'):
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            # The PI is of XML style (<?as df?>) but BeautifulSoup
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            # interpreted it as being SGML style (<?as df>). Fix.
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            bs_node = bs_node[:-1]
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        res = etree.ProcessingInstruction(*bs_node.split(' ', 1))
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        if parent is not None:
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            parent.append(res)
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        return res
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    @converter(NavigableString)
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    def convert_text(bs_node, parent):
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        if parent is not None:
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            append_text(parent, unescape(bs_node))
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        return None
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    return convert_node
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# copied from ET's ElementSoup
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try:
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    from html.entities import name2codepoint  # Python 3
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except ImportError:
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    from htmlentitydefs import name2codepoint
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handle_entities = re.compile(r"&(\w+);").sub
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try:
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    unichr
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except NameError:
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    # Python 3
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    unichr = chr
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def unescape(string):
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    if not string:
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        return ''
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    # work around oddities in BeautifulSoup's entity handling
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    def unescape_entity(m):
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        try:
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            return unichr(name2codepoint[m.group(1)])
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        except KeyError:
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            return m.group(0)  # use as is
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    return handle_entities(unescape_entity, string)
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