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This library is unmaintained, outdated and plugin authors are encouraged to use html.parser from Python Standard Library instead. https://docs.python.org/3/library/html.parser.html PR #19068.adaptive-webui-19844
Chocobo1
2 years ago
committed by
GitHub
3 changed files with 0 additions and 549 deletions
@ -1,547 +0,0 @@
@@ -1,547 +0,0 @@
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"""A parser for SGML, using the derived class as a static DTD.""" |
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# XXX This only supports those SGML features used by HTML. |
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# XXX There should be a way to distinguish between PCDATA (parsed |
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# character data -- the normal case), RCDATA (replaceable character |
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# data -- only char and entity references and end tags are special) |
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# and CDATA (character data -- only end tags are special). RCDATA is |
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# not supported at all. |
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import _markupbase |
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import re |
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__all__ = ["SGMLParser", "SGMLParseError"] |
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# Regular expressions used for parsing |
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interesting = re.compile('[&<]') |
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incomplete = re.compile('&([a-zA-Z][a-zA-Z0-9]*|#[0-9]*)?|' |
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'<([a-zA-Z][^<>]*|' |
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'/([a-zA-Z][^<>]*)?|' |
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'![^<>]*)?') |
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entityref = re.compile('&([a-zA-Z][-.a-zA-Z0-9]*)[^a-zA-Z0-9]') |
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charref = re.compile('&#([0-9]+)[^0-9]') |
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starttagopen = re.compile('<[>a-zA-Z]') |
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shorttagopen = re.compile('<[a-zA-Z][-.a-zA-Z0-9]*/') |
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shorttag = re.compile('<([a-zA-Z][-.a-zA-Z0-9]*)/([^/]*)/') |
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piclose = re.compile('>') |
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endbracket = re.compile('[<>]') |
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tagfind = re.compile('[a-zA-Z][-_.a-zA-Z0-9]*') |
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attrfind = re.compile( |
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r'\s*([a-zA-Z_][-:.a-zA-Z_0-9]*)(\s*=\s*' |
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r'(\'[^\']*\'|"[^"]*"|[][\-a-zA-Z0-9./,:;+*%?!&$\(\)_#=~\'"@]*))?') |
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class SGMLParseError(RuntimeError): |
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"""Exception raised for all parse errors.""" |
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pass |
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# SGML parser base class -- find tags and call handler functions. |
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# Usage: p = SGMLParser(); p.feed(data); ...; p.close(). |
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# The dtd is defined by deriving a class which defines methods |
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# with special names to handle tags: start_foo and end_foo to handle |
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# <foo> and </foo>, respectively, or do_foo to handle <foo> by itself. |
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# (Tags are converted to lower case for this purpose.) The data |
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# between tags is passed to the parser by calling self.handle_data() |
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# with some data as argument (the data may be split up in arbitrary |
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# chunks). Entity references are passed by calling |
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# self.handle_entityref() with the entity reference as argument. |
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class SGMLParser(_markupbase.ParserBase): |
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# Definition of entities -- derived classes may override |
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entity_or_charref = re.compile('&(?:' |
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'([a-zA-Z][-.a-zA-Z0-9]*)|#([0-9]+)' |
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')(;?)') |
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def __init__(self, verbose=0): |
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"""Initialize and reset this instance.""" |
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self.verbose = verbose |
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self.reset() |
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def reset(self): |
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"""Reset this instance. Loses all unprocessed data.""" |
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self.__starttag_text = None |
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self.rawdata = '' |
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self.stack = [] |
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self.lasttag = '???' |
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self.nomoretags = 0 |
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self.literal = 0 |
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_markupbase.ParserBase.reset(self) |
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def setnomoretags(self): |
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"""Enter literal mode (CDATA) till EOF. |
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Intended for derived classes only. |
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""" |
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self.nomoretags = self.literal = 1 |
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def setliteral(self, *args): |
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"""Enter literal mode (CDATA). |
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Intended for derived classes only. |
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""" |
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self.literal = 1 |
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def feed(self, data): |
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"""Feed some data to the parser. |
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Call this as often as you want, with as little or as much text |
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as you want (may include '\n'). (This just saves the text, |
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all the processing is done by goahead().) |
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""" |
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self.rawdata = self.rawdata + data |
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self.goahead(0) |
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def close(self): |
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"""Handle the remaining data.""" |
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self.goahead(1) |
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def error(self, message): |
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raise SGMLParseError(message) |
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# Internal -- handle data as far as reasonable. May leave state |
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# and data to be processed by a subsequent call. If 'end' is |
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# true, force handling all data as if followed by EOF marker. |
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def goahead(self, end): |
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rawdata = self.rawdata |
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i = 0 |
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n = len(rawdata) |
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while i < n: |
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if self.nomoretags: |
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self.handle_data(rawdata[i:n]) |
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i = n |
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break |
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match = interesting.search(rawdata, i) |
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if match: j = match.start() |
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else: j = n |
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if i < j: |
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self.handle_data(rawdata[i:j]) |
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i = j |
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if i == n: break |
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if rawdata[i] == '<': |
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if starttagopen.match(rawdata, i): |
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if self.literal: |
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self.handle_data(rawdata[i]) |
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i = i+1 |
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continue |
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k = self.parse_starttag(i) |
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if k < 0: break |
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i = k |
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continue |
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if rawdata.startswith("</", i): |
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k = self.parse_endtag(i) |
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if k < 0: break |
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i = k |
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self.literal = 0 |
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continue |
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if self.literal: |
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if n > (i + 1): |
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self.handle_data("<") |
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i = i+1 |
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else: |
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# incomplete |
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break |
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continue |
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if rawdata.startswith("<!--", i): |
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# Strictly speaking, a comment is --.*-- |
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# within a declaration tag <!...>. |
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# This should be removed, |
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# and comments handled only in parse_declaration. |
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k = self.parse_comment(i) |
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if k < 0: break |
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i = k |
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continue |
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if rawdata.startswith("<?", i): |
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k = self.parse_pi(i) |
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if k < 0: break |
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i = i+k |
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continue |
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if rawdata.startswith("<!", i): |
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# This is some sort of declaration; in "HTML as |
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# deployed," this should only be the document type |
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# declaration ("<!DOCTYPE html...>"). |
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k = self.parse_declaration(i) |
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if k < 0: break |
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i = k |
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continue |
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elif rawdata[i] == '&': |
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if self.literal: |
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self.handle_data(rawdata[i]) |
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i = i+1 |
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continue |
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match = charref.match(rawdata, i) |
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if match: |
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name = match.group(1) |
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self.handle_charref(name) |
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i = match.end(0) |
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if rawdata[i-1] != ';': i = i-1 |
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continue |
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match = entityref.match(rawdata, i) |
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if match: |
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name = match.group(1) |
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self.handle_entityref(name) |
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i = match.end(0) |
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if rawdata[i-1] != ';': i = i-1 |
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continue |
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else: |
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self.error('neither < nor & ??') |
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# We get here only if incomplete matches but |
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# nothing else |
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match = incomplete.match(rawdata, i) |
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if not match: |
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self.handle_data(rawdata[i]) |
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i = i+1 |
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continue |
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j = match.end(0) |
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if j == n: |
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break # Really incomplete |
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self.handle_data(rawdata[i:j]) |
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i = j |
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# end while |
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if end and i < n: |
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self.handle_data(rawdata[i:n]) |
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i = n |
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self.rawdata = rawdata[i:] |
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# XXX if end: check for empty stack |
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# Extensions for the DOCTYPE scanner: |
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_decl_otherchars = '=' |
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# Internal -- parse processing instr, return length or -1 if not terminated |
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def parse_pi(self, i): |
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rawdata = self.rawdata |
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if rawdata[i:i+2] != '<?': |
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self.error('unexpected call to parse_pi()') |
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match = piclose.search(rawdata, i+2) |
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if not match: |
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return -1 |
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j = match.start(0) |
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self.handle_pi(rawdata[i+2: j]) |
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j = match.end(0) |
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return j-i |
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def get_starttag_text(self): |
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return self.__starttag_text |
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# Internal -- handle starttag, return length or -1 if not terminated |
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def parse_starttag(self, i): |
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self.__starttag_text = None |
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start_pos = i |
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rawdata = self.rawdata |
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if shorttagopen.match(rawdata, i): |
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# SGML shorthand: <tag/data/ == <tag>data</tag> |
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# XXX Can data contain &... (entity or char refs)? |
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# XXX Can data contain < or > (tag characters)? |
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# XXX Can there be whitespace before the first /? |
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match = shorttag.match(rawdata, i) |
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if not match: |
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return -1 |
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tag, data = match.group(1, 2) |
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self.__starttag_text = '<%s/' % tag |
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tag = tag.lower() |
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k = match.end(0) |
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self.finish_shorttag(tag, data) |
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self.__starttag_text = rawdata[start_pos:match.end(1) + 1] |
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return k |
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# XXX The following should skip matching quotes (' or ") |
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# As a shortcut way to exit, this isn't so bad, but shouldn't |
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# be used to locate the actual end of the start tag since the |
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# < or > characters may be embedded in an attribute value. |
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match = endbracket.search(rawdata, i+1) |
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if not match: |
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return -1 |
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j = match.start(0) |
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# Now parse the data between i+1 and j into a tag and attrs |
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attrs = [] |
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if rawdata[i:i+2] == '<>': |
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# SGML shorthand: <> == <last open tag seen> |
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k = j |
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tag = self.lasttag |
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else: |
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match = tagfind.match(rawdata, i+1) |
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if not match: |
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self.error('unexpected call to parse_starttag') |
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k = match.end(0) |
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tag = rawdata[i+1:k].lower() |
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self.lasttag = tag |
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while k < j: |
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match = attrfind.match(rawdata, k) |
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if not match: break |
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attrname, rest, attrvalue = match.group(1, 2, 3) |
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if not rest: |
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attrvalue = attrname |
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else: |
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if (attrvalue[:1] == "'" == attrvalue[-1:] or |
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attrvalue[:1] == '"' == attrvalue[-1:]): |
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# strip quotes |
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attrvalue = attrvalue[1:-1] |
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attrvalue = self.entity_or_charref.sub( |
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self._convert_ref, attrvalue) |
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attrs.append((attrname.lower(), attrvalue)) |
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k = match.end(0) |
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if rawdata[j] == '>': |
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j = j+1 |
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self.__starttag_text = rawdata[start_pos:j] |
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self.finish_starttag(tag, attrs) |
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return j |
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# Internal -- convert entity or character reference |
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def _convert_ref(self, match): |
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if match.group(2): |
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return self.convert_charref(match.group(2)) or \ |
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'&#%s%s' % match.groups()[1:] |
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elif match.group(3): |
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return self.convert_entityref(match.group(1)) or \ |
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'&%s;' % match.group(1) |
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else: |
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return '&%s' % match.group(1) |
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# Internal -- parse endtag |
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def parse_endtag(self, i): |
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rawdata = self.rawdata |
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match = endbracket.search(rawdata, i+1) |
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if not match: |
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return -1 |
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j = match.start(0) |
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tag = rawdata[i+2:j].strip().lower() |
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if rawdata[j] == '>': |
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j = j+1 |
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self.finish_endtag(tag) |
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return j |
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# Internal -- finish parsing of <tag/data/ (same as <tag>data</tag>) |
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def finish_shorttag(self, tag, data): |
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self.finish_starttag(tag, []) |
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self.handle_data(data) |
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self.finish_endtag(tag) |
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# Internal -- finish processing of start tag |
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# Return -1 for unknown tag, 0 for open-only tag, 1 for balanced tag |
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def finish_starttag(self, tag, attrs): |
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try: |
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method = getattr(self, 'start_' + tag) |
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except AttributeError: |
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try: |
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method = getattr(self, 'do_' + tag) |
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except AttributeError: |
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self.unknown_starttag(tag, attrs) |
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return -1 |
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else: |
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self.handle_starttag(tag, method, attrs) |
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return 0 |
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else: |
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self.stack.append(tag) |
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self.handle_starttag(tag, method, attrs) |
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return 1 |
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# Internal -- finish processing of end tag |
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def finish_endtag(self, tag): |
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if not tag: |
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found = len(self.stack) - 1 |
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if found < 0: |
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self.unknown_endtag(tag) |
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return |
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else: |
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if tag not in self.stack: |
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try: |
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method = getattr(self, 'end_' + tag) |
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except AttributeError: |
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self.unknown_endtag(tag) |
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else: |
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self.report_unbalanced(tag) |
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return |
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found = len(self.stack) |
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for i in range(found): |
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if self.stack[i] == tag: found = i |
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while len(self.stack) > found: |
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tag = self.stack[-1] |
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try: |
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method = getattr(self, 'end_' + tag) |
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except AttributeError: |
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method = None |
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if method: |
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self.handle_endtag(tag, method) |
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else: |
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self.unknown_endtag(tag) |
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del self.stack[-1] |
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# Overridable -- handle start tag |
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def handle_starttag(self, tag, method, attrs): |
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method(attrs) |
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# Overridable -- handle end tag |
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def handle_endtag(self, tag, method): |
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method() |
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# Example -- report an unbalanced </...> tag. |
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def report_unbalanced(self, tag): |
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if self.verbose: |
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print('*** Unbalanced </' + tag + '>') |
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print('*** Stack:', self.stack) |
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def convert_charref(self, name): |
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"""Convert character reference, may be overridden.""" |
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try: |
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n = int(name) |
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except ValueError: |
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return |
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if not 0 <= n <= 127: |
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return |
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return self.convert_codepoint(n) |
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def convert_codepoint(self, codepoint): |
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return chr(codepoint) |
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def handle_charref(self, name): |
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"""Handle character reference, no need to override.""" |
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replacement = self.convert_charref(name) |
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if replacement is None: |
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self.unknown_charref(name) |
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else: |
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self.handle_data(replacement) |
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# Definition of entities -- derived classes may override |
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entitydefs = \ |
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{'lt': '<', 'gt': '>', 'amp': '&', 'quot': '"', 'apos': '\''} |
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def convert_entityref(self, name): |
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"""Convert entity references. |
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As an alternative to overriding this method; one can tailor the |
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results by setting up the self.entitydefs mapping appropriately. |
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""" |
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table = self.entitydefs |
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if name in table: |
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return table[name] |
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else: |
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return |
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|
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def handle_entityref(self, name): |
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"""Handle entity references, no need to override.""" |
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replacement = self.convert_entityref(name) |
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if replacement is None: |
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self.unknown_entityref(name) |
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else: |
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self.handle_data(replacement) |
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# Example -- handle data, should be overridden |
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def handle_data(self, data): |
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pass |
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# Example -- handle comment, could be overridden |
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def handle_comment(self, data): |
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pass |
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|
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# Example -- handle declaration, could be overridden |
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def handle_decl(self, decl): |
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pass |
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|
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# Example -- handle processing instruction, could be overridden |
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def handle_pi(self, data): |
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pass |
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# To be overridden -- handlers for unknown objects |
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def unknown_starttag(self, tag, attrs): pass |
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def unknown_endtag(self, tag): pass |
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def unknown_charref(self, ref): pass |
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def unknown_entityref(self, ref): pass |
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|
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class TestSGMLParser(SGMLParser): |
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def __init__(self, verbose=0): |
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self.testdata = "" |
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SGMLParser.__init__(self, verbose) |
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def handle_data(self, data): |
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self.testdata = self.testdata + data |
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if len(repr(self.testdata)) >= 70: |
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self.flush() |
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|
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def flush(self): |
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data = self.testdata |
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if data: |
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self.testdata = "" |
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print('data:', repr(data)) |
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|
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def handle_comment(self, data): |
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self.flush() |
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r = repr(data) |
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if len(r) > 68: |
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r = r[:32] + '...' + r[-32:] |
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print('comment:', r) |
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|
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def unknown_starttag(self, tag, attrs): |
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self.flush() |
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if not attrs: |
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print('start tag: <' + tag + '>') |
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else: |
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print('start tag: <' + tag, end=' ') |
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for name, value in attrs: |
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print(name + '=' + '"' + value + '"', end=' ') |
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print('>') |
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|
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def unknown_endtag(self, tag): |
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self.flush() |
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print('end tag: </' + tag + '>') |
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|
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def unknown_entityref(self, ref): |
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self.flush() |
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print('*** unknown entity ref: &' + ref + ';') |
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|
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def unknown_charref(self, ref): |
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self.flush() |
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print('*** unknown char ref: &#' + ref + ';') |
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|
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def unknown_decl(self, data): |
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self.flush() |
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print('*** unknown decl: [' + data + ']') |
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|
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def close(self): |
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SGMLParser.close(self) |
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self.flush() |
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|
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|
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def test(args = None): |
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import sys |
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|
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if args is None: |
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args = sys.argv[1:] |
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|
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if args and args[0] == '-s': |
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args = args[1:] |
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klass = SGMLParser |
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else: |
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klass = TestSGMLParser |
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|
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if args: |
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file = args[0] |
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else: |
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file = 'test.html' |
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|
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if file == '-': |
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f = sys.stdin |
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else: |
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try: |
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f = open(file, 'r') |
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except IOError as msg: |
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print(file, ":", msg) |
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sys.exit(1) |
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|
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data = f.read() |
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if f is not sys.stdin: |
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f.close() |
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|
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x = klass() |
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for c in data: |
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x.feed(c) |
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x.close() |
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|
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|
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if __name__ == '__main__': |
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test() |
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