# 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
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
from . import tokens
from .errors import ParserError
from ..nodes import (
Argument,
Comment,
ExternalLink,
Heading,
HTMLEntity,
Tag,
Template,
Text,
Wikilink,
)
from ..nodes.extras import Attribute, Parameter
from ..smart_list import SmartList
from ..wikicode import Wikicode
__all__ = ["Builder"]
_HANDLERS = {tokens.Text: lambda self, token: Text(token.text)}
def _add_handler(token_type):
"""Create a decorator that adds a handler function to the lookup table."""
def decorator(func):
"""Add a handler function to the lookup table."""
_HANDLERS[token_type] = func
return func
return decorator
[docs]
class Builder:
"""Builds a tree of nodes out of a sequence of tokens.
To use, pass a list of :class:`.Token`\\ s to the :meth:`build` method. The
list will be exhausted as it is parsed and a :class:`.Wikicode` object
containing the node tree will be returned.
"""
def __init__(self):
self._tokens = []
self._stacks = []
[docs]
def _push(self):
"""Push a new node list onto the stack."""
self._stacks.append([])
[docs]
def _pop(self):
"""Pop the current node list off of the stack.
The raw node list is wrapped in a :class:`.SmartList` and then in a
:class:`.Wikicode` object.
"""
return Wikicode(SmartList(self._stacks.pop()))
[docs]
def _write(self, item):
"""Append a node to the current node list."""
self._stacks[-1].append(item)
[docs]
def _handle_parameter(self, default):
"""Handle a case where a parameter is at the head of the tokens.
*default* is the value to use if no parameter name is defined.
"""
key = None
showkey = False
self._push()
while self._tokens:
token = self._tokens.pop()
if isinstance(token, tokens.TemplateParamEquals):
key = self._pop()
showkey = True
self._push()
elif isinstance(
token, (tokens.TemplateParamSeparator, tokens.TemplateClose)
):
self._tokens.append(token)
value = self._pop()
if key is None:
key = Wikicode(SmartList([Text(str(default))]))
return Parameter(key, value, showkey)
else:
self._write(self._handle_token(token))
raise ParserError("_handle_parameter() missed a close token")
[docs]
@_add_handler(tokens.TemplateOpen)
def _handle_template(self, token):
"""Handle a case where a template is at the head of the tokens."""
params = []
default = 1
self._push()
while self._tokens:
token = self._tokens.pop()
if isinstance(token, tokens.TemplateParamSeparator):
if not params:
name = self._pop()
param = self._handle_parameter(default)
params.append(param)
if not param.showkey:
default += 1
elif isinstance(token, tokens.TemplateClose):
if not params:
name = self._pop()
return Template(name, params)
else:
self._write(self._handle_token(token))
raise ParserError("_handle_template() missed a close token")
[docs]
@_add_handler(tokens.ArgumentOpen)
def _handle_argument(self, token):
"""Handle a case where an argument is at the head of the tokens."""
name = None
self._push()
while self._tokens:
token = self._tokens.pop()
if isinstance(token, tokens.ArgumentSeparator):
name = self._pop()
self._push()
elif isinstance(token, tokens.ArgumentClose):
if name is not None:
return Argument(name, self._pop())
return Argument(self._pop())
else:
self._write(self._handle_token(token))
raise ParserError("_handle_argument() missed a close token")
[docs]
@_add_handler(tokens.WikilinkOpen)
def _handle_wikilink(self, token):
"""Handle a case where a wikilink is at the head of the tokens."""
title = None
self._push()
while self._tokens:
token = self._tokens.pop()
if isinstance(token, tokens.WikilinkSeparator):
title = self._pop()
self._push()
elif isinstance(token, tokens.WikilinkClose):
if title is not None:
return Wikilink(title, self._pop())
return Wikilink(self._pop())
else:
self._write(self._handle_token(token))
raise ParserError("_handle_wikilink() missed a close token")
[docs]
@_add_handler(tokens.ExternalLinkOpen)
def _handle_external_link(self, token):
"""Handle when an external link is at the head of the tokens."""
brackets, url, suppress_space = token.brackets, None, None
self._push()
while self._tokens:
token = self._tokens.pop()
if isinstance(token, tokens.ExternalLinkSeparator):
url = self._pop()
suppress_space = token.suppress_space
self._push()
elif isinstance(token, tokens.ExternalLinkClose):
if url is not None:
return ExternalLink(
url,
self._pop(),
brackets=brackets,
suppress_space=suppress_space is True,
)
return ExternalLink(
self._pop(),
brackets=brackets,
suppress_space=suppress_space is True,
)
else:
self._write(self._handle_token(token))
raise ParserError("_handle_external_link() missed a close token")
[docs]
@_add_handler(tokens.HTMLEntityStart)
def _handle_entity(self, token):
"""Handle a case where an HTML entity is at the head of the tokens."""
token = self._tokens.pop()
if isinstance(token, tokens.HTMLEntityNumeric):
token = self._tokens.pop()
if isinstance(token, tokens.HTMLEntityHex):
text = self._tokens.pop()
self._tokens.pop() # Remove HTMLEntityEnd
return HTMLEntity(
text.text, named=False, hexadecimal=True, hex_char=token.char
)
self._tokens.pop() # Remove HTMLEntityEnd
return HTMLEntity(token.text, named=False, hexadecimal=False)
self._tokens.pop() # Remove HTMLEntityEnd
return HTMLEntity(token.text, named=True, hexadecimal=False)
[docs]
@_add_handler(tokens.HeadingStart)
def _handle_heading(self, token):
"""Handle a case where a heading is at the head of the tokens."""
level = token.level
self._push()
while self._tokens:
token = self._tokens.pop()
if isinstance(token, tokens.HeadingEnd):
title = self._pop()
return Heading(title, level)
self._write(self._handle_token(token))
raise ParserError("_handle_heading() missed a close token")
[docs]
def _handle_attribute(self, start):
"""Handle a case where a tag attribute is at the head of the tokens."""
name = quotes = None
self._push()
while self._tokens:
token = self._tokens.pop()
if isinstance(token, tokens.TagAttrEquals):
name = self._pop()
self._push()
elif isinstance(token, tokens.TagAttrQuote):
quotes = token.char
elif isinstance(
token,
(tokens.TagAttrStart, tokens.TagCloseOpen, tokens.TagCloseSelfclose),
):
self._tokens.append(token)
if name:
value = self._pop()
else:
name, value = self._pop(), None
return Attribute(
name,
value,
quotes,
start.pad_first,
start.pad_before_eq,
start.pad_after_eq,
)
else:
self._write(self._handle_token(token))
raise ParserError("_handle_attribute() missed a close token")
[docs]
@_add_handler(tokens.TagOpenOpen)
def _handle_tag(self, token):
"""Handle a case where a tag is at the head of the tokens."""
close_tokens = (tokens.TagCloseSelfclose, tokens.TagCloseClose)
implicit, attrs, contents, closing_tag = False, [], None, None
wiki_markup, invalid = token.wiki_markup, token.invalid or False
wiki_style_separator, closing_wiki_markup = None, wiki_markup
self._push()
while self._tokens:
token = self._tokens.pop()
if isinstance(token, tokens.TagAttrStart):
attrs.append(self._handle_attribute(token))
elif isinstance(token, tokens.TagCloseOpen):
wiki_style_separator = token.wiki_markup
padding = token.padding or ""
tag = self._pop()
self._push()
elif isinstance(token, tokens.TagOpenClose):
closing_wiki_markup = token.wiki_markup
contents = self._pop()
self._push()
elif isinstance(token, close_tokens):
if isinstance(token, tokens.TagCloseSelfclose):
closing_wiki_markup = token.wiki_markup
tag = self._pop()
self_closing = True
padding = token.padding or ""
implicit = token.implicit or False
else:
self_closing = False
closing_tag = self._pop()
return Tag(
tag,
contents,
attrs,
wiki_markup,
self_closing,
invalid,
implicit,
padding,
closing_tag,
wiki_style_separator,
closing_wiki_markup,
)
else:
self._write(self._handle_token(token))
raise ParserError("_handle_tag() missed a close token")
[docs]
def _handle_token(self, token):
"""Handle a single token."""
try:
return _HANDLERS[type(token)](self, token)
except KeyError:
err = "_handle_token() got unexpected {0}"
raise ParserError(err.format(type(token).__name__)) from None
[docs]
def build(self, tokenlist):
"""Build a Wikicode object from a list tokens and return it."""
self._tokens = tokenlist
self._tokens.reverse()
self._push()
while self._tokens:
node = self._handle_token(self._tokens.pop())
self._write(node)
return self._pop()
del _add_handler