"""Docutils transforms used by Sphinx when reading documents."""
import re
import unicodedata
import warnings
from typing import TYPE_CHECKING, Any, Dict, Generator, List, Optional, Tuple, cast
from docutils import nodes
from docutils.nodes import Element, Node, Text
from docutils.transforms import Transform, Transformer
from docutils.transforms.parts import ContentsFilter
from docutils.transforms.universal import SmartQuotes
from docutils.utils import normalize_language_tag
from docutils.utils.smartquotes import smartchars
from sphinx import addnodes
from sphinx.config import Config
from sphinx.deprecation import RemovedInSphinx60Warning
from sphinx.locale import _, __
from sphinx.util import docutils, logging
from sphinx.util.docutils import new_document
from sphinx.util.i18n import format_date
from sphinx.util.nodes import NodeMatcher, apply_source_workaround, is_smartquotable
if TYPE_CHECKING:
from sphinx.application import Sphinx
from sphinx.domain.std import StandardDomain
from sphinx.environment import BuildEnvironment
logger = logging.getLogger(__name__)
default_substitutions = {
'version',
'release',
'today',
}
class SphinxTransform(Transform):
"""A base class of Transforms.
Compared with ``docutils.transforms.Transform``, this class improves accessibility to
Sphinx APIs.
"""
@property
def app(self) -> "Sphinx":
"""Reference to the :class:`.Sphinx` object."""
return self.env.app
@property
def env(self) -> "BuildEnvironment":
"""Reference to the :class:`.BuildEnvironment` object."""
return self.document.settings.env
@property
def config(self) -> Config:
"""Reference to the :class:`.Config` object."""
return self.env.config
class SphinxTransformer(Transformer):
"""
A transformer for Sphinx.
"""
document: nodes.document
env: Optional["BuildEnvironment"] = None
def set_environment(self, env: "BuildEnvironment") -> None:
self.env = env
def apply_transforms(self) -> None:
if isinstance(self.document, nodes.document):
if not hasattr(self.document.settings, 'env') and self.env:
self.document.settings.env = self.env
super().apply_transforms()
else:
# wrap the target node by document node during transforming
try:
document = new_document('')
if self.env:
document.settings.env = self.env
document += self.document
self.document = document
super().apply_transforms()
finally:
self.document = self.document[0]
class DefaultSubstitutions(SphinxTransform):
"""
Replace some substitutions if they aren't defined in the document.
"""
# run before the default Substitutions
default_priority = 210
def apply(self, **kwargs: Any) -> None:
# only handle those not otherwise defined in the document
to_handle = default_substitutions - set(self.document.substitution_defs)
for ref in self.document.findall(nodes.substitution_reference):
refname = ref['refname']
if refname in to_handle:
text = self.config[refname]
if refname == 'today' and not text:
# special handling: can also specify a strftime format
text = format_date(self.config.today_fmt or _('%b %d, %Y'),
language=self.config.language)
ref.replace_self(nodes.Text(text, text))
class MoveModuleTargets(SphinxTransform):
"""
Move module targets that are the first thing in a section to the section
title.
XXX Python specific
"""
default_priority = 210
def apply(self, **kwargs: Any) -> None:
for node in list(self.document.findall(nodes.target)):
if not node['ids']:
continue
if ('ismod' in node and
node.parent.__class__ is nodes.section and
# index 0 is the section title node
node.parent.index(node) == 1):
node.parent['ids'][0:0] = node['ids']
node.parent.remove(node)
class HandleCodeBlocks(SphinxTransform):
"""
Several code block related transformations.
"""
default_priority = 210
def apply(self, **kwargs: Any) -> None:
# move doctest blocks out of blockquotes
for node in self.document.findall(nodes.block_quote):
if all(isinstance(child, nodes.doctest_block) for child
in node.children):
node.replace_self(node.children)
# combine successive doctest blocks
# for node in self.document.findall(nodes.doctest_block):
# if node not in node.parent.children:
# continue
# parindex = node.parent.index(node)
# while len(node.parent) > parindex+1 and \
# isinstance(node.parent[parindex+1], nodes.doctest_block):
# node[0] = nodes.Text(node[0] + '\n\n' +
# node.parent[parindex+1][0])
# del node.parent[parindex+1]
class AutoNumbering(SphinxTransform):
"""
Register IDs of tables, figures and literal_blocks to assign numbers.
"""
default_priority = 210
def apply(self, **kwargs: Any) -> None:
domain: StandardDomain = self.env.get_domain('std')
for node in self.document.findall(nodes.Element):
if (domain.is_enumerable_node(node) and
domain.get_numfig_title(node) is not None and
node['ids'] == []):
self.document.note_implicit_target(node)
class SortIds(SphinxTransform):
"""
Sort section IDs so that the "id[0-9]+" one comes last.
"""
default_priority = 261
def apply(self, **kwargs: Any) -> None:
for node in self.document.findall(nodes.section):
if len(node['ids']) > 1 and node['ids'][0].startswith('id'):
node['ids'] = node['ids'][1:] + [node['ids'][0]]
TRANSLATABLE_NODES = {
'literal-block': nodes.literal_block,
'doctest-block': nodes.doctest_block,
'raw': nodes.raw,
'index': addnodes.index,
'image': nodes.image,
}
class ApplySourceWorkaround(SphinxTransform):
"""
Update source and rawsource attributes
"""
default_priority = 10
def apply(self, **kwargs: Any) -> None:
for node in self.document.findall(): # type: Node
if isinstance(node, (nodes.TextElement, nodes.image, nodes.topic)):
apply_source_workaround(node)
class AutoIndexUpgrader(SphinxTransform):
"""
Detect old style (4 column based indices) and automatically upgrade to new style.
"""
default_priority = 210
def apply(self, **kwargs: Any) -> None:
for node in self.document.findall(addnodes.index):
if 'entries' in node and any(len(entry) == 4 for entry in node['entries']):
msg = __('4 column based index found. '
'It might be a bug of extensions you use: %r') % node['entries']
logger.warning(msg, location=node)
for i, entry in enumerate(node['entries']):
if len(entry) == 4:
node['entries'][i] = entry + (None,)
class ExtraTranslatableNodes(SphinxTransform):
"""
Make nodes translatable
"""
default_priority = 10
def apply(self, **kwargs: Any) -> None:
targets = self.config.gettext_additional_targets
target_nodes = [v for k, v in TRANSLATABLE_NODES.items() if k in targets]
if not target_nodes:
return
def is_translatable_node(node: Node) -> bool:
return isinstance(node, tuple(target_nodes))
for node in self.document.findall(is_translatable_node): # type: Element
node['translatable'] = True
class UnreferencedFootnotesDetector(SphinxTransform):
"""
Detect unreferenced footnotes and emit warnings
"""
default_priority = 200
def apply(self, **kwargs: Any) -> None:
for node in self.document.footnotes:
if node['names'] == []:
# footnote having duplicated number. It is already warned at parser.
pass
elif node['names'][0] not in self.document.footnote_refs:
logger.warning(__('Footnote [%s] is not referenced.'), node['names'][0],
type='ref', subtype='footnote',
location=node)
for node in self.document.autofootnotes:
if not any(ref['auto'] == node['auto'] for ref in self.document.autofootnote_refs):
logger.warning(__('Footnote [#] is not referenced.'),
type='ref', subtype='footnote',
location=node)
class DoctestTransform(SphinxTransform):
"""Set "doctest" style to each doctest_block node"""
default_priority = 500
def apply(self, **kwargs: Any) -> None:
for node in self.document.findall(nodes.doctest_block):
node['classes'].append('doctest')
class FigureAligner(SphinxTransform):
"""
Align figures to center by default.
"""
default_priority = 700
def __init__(self, *args: Any, **kwargs: Any) -> None:
warnings.warn('FigureAilgner is deprecated.',
RemovedInSphinx60Warning)
super().__init__(*args, **kwargs)
def apply(self, **kwargs: Any) -> None:
matcher = NodeMatcher(nodes.table, nodes.figure)
for node in self.document.findall(matcher): # type: Element
node.setdefault('align', 'default')
class FilterSystemMessages(SphinxTransform):
"""Filter system messages from a doctree."""
default_priority = 999
def apply(self, **kwargs: Any) -> None:
filterlevel = 2 if self.config.keep_warnings else 5
for node in list(self.document.findall(nodes.system_message)):
if node['level'] < filterlevel:
logger.debug('%s [filtered system message]', node.astext())
node.parent.remove(node)
class SphinxContentsFilter(ContentsFilter):
"""
Used with BuildEnvironment.add_toc_from() to discard cross-file links
within table-of-contents link nodes.
"""
visit_pending_xref = ContentsFilter.ignore_node_but_process_children
def visit_image(self, node: nodes.image) -> None:
raise nodes.SkipNode
class SphinxSmartQuotes(SmartQuotes, SphinxTransform):
"""
Customized SmartQuotes to avoid transform for some extra node types.
refs: sphinx.parsers.RSTParser
"""
default_priority = 750
def apply(self, **kwargs: Any) -> None:
if not self.is_available():
return
# override default settings with :confval:`smartquotes_action`
self.smartquotes_action = self.config.smartquotes_action
super().apply()
def is_available(self) -> bool:
builders = self.config.smartquotes_excludes.get('builders', [])
languages = self.config.smartquotes_excludes.get('languages', [])
if self.document.settings.smart_quotes is False:
# disabled by 3rd party extension (workaround)
return False
elif self.config.smartquotes is False:
# disabled by confval smartquotes
return False
elif self.app.builder.name in builders:
# disabled by confval smartquotes_excludes['builders']
return False
elif self.config.language in languages:
# disabled by confval smartquotes_excludes['languages']
return False
# confirm selected language supports smart_quotes or not
language = self.env.settings['language_code']
for tag in normalize_language_tag(language):
if tag in smartchars.quotes:
return True
else:
return False
def get_tokens(self, txtnodes: List[Text]) -> Generator[Tuple[str, str], None, None]:
# A generator that yields ``(texttype, nodetext)`` tuples for a list
# of "Text" nodes (interface to ``smartquotes.educate_tokens()``).
for txtnode in txtnodes:
if is_smartquotable(txtnode):
if docutils.__version_info__ >= (0, 16):
# SmartQuotes uses backslash escapes instead of null-escapes
text = re.sub(r'(?<=\x00)([-\\\'".`])', r'\\\1', str(txtnode))
else:
text = txtnode.astext()
yield ('plain', text)
else:
# skip smart quotes
yield ('literal', txtnode.astext())
class DoctreeReadEvent(SphinxTransform):
"""Emit :event:`doctree-read` event."""
default_priority = 880
def apply(self, **kwargs: Any) -> None:
self.app.emit('doctree-read', self.document)
class ManpageLink(SphinxTransform):
"""Find manpage section numbers and names"""
default_priority = 999
def apply(self, **kwargs: Any) -> None:
for node in self.document.findall(addnodes.manpage):
manpage = ' '.join([str(x) for x in node.children
if isinstance(x, nodes.Text)])
pattern = r'^(?P<path>(?P<page>.+)[\(\.](?P<section>[1-9]\w*)?\)?)$' # noqa
info = {'path': manpage,
'page': manpage,
'section': ''}
r = re.match(pattern, manpage)
if r:
info = r.groupdict()
node.attributes.update(info)
class GlossarySorter(SphinxTransform):
"""Sort glossaries that have the ``sorted`` flag."""
# This must be done after i18n, therefore not right
# away in the glossary directive.
default_priority = 500
def apply(self, **kwargs: Any) -> None:
for glossary in self.document.findall(addnodes.glossary):
if glossary["sorted"]:
definition_list = cast(nodes.definition_list, glossary[0])
definition_list[:] = sorted(
definition_list,
key=lambda item: unicodedata.normalize(
'NFD',
cast(nodes.term, item)[0].astext().lower())
)
def setup(app: "Sphinx") -> Dict[str, Any]:
app.add_transform(ApplySourceWorkaround)
app.add_transform(ExtraTranslatableNodes)
app.add_transform(DefaultSubstitutions)
app.add_transform(MoveModuleTargets)
app.add_transform(HandleCodeBlocks)
app.add_transform(SortIds)
app.add_transform(DoctestTransform)
app.add_transform(AutoNumbering)
app.add_transform(AutoIndexUpgrader)
app.add_transform(FilterSystemMessages)
app.add_transform(UnreferencedFootnotesDetector)
app.add_transform(SphinxSmartQuotes)
app.add_transform(DoctreeReadEvent)
app.add_transform(ManpageLink)
app.add_transform(GlossarySorter)
return {
'version': 'builtin',
'parallel_read_safe': True,
'parallel_write_safe': True,
}