"""Docutils transforms used by Sphinx when reading documents."""
from __future__ import annotations
import re
import unicodedata
from typing import TYPE_CHECKING, Any, cast
from docutils import nodes
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.locale import _, __
from sphinx.util import logging
from sphinx.util.docutils import new_document
from sphinx.util.i18n import format_date
from sphinx.util.nodes import apply_source_workaround, is_smartquotable
if TYPE_CHECKING:
from collections.abc import Generator
from docutils.nodes import Node, Text
from sphinx.application import Sphinx
from sphinx.config import Config
from sphinx.domains.std import StandardDomain
from sphinx.environment import BuildEnvironment
logger = logging.getLogger(__name__)
default_substitutions = {
'version',
'release',
'today',
'translation progress',
}
class SphinxTransformer(Transformer):
"""
A transformer for Sphinx.
"""
document: nodes.document
env: BuildEnvironment | None = 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:
if refname == 'translation progress':
# special handling: calculate translation progress
text = _calculate_translation_progress(self.document)
else:
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))
def _calculate_translation_progress(document: nodes.document) -> str:
try:
translation_progress = document['translation_progress']
except KeyError:
return _('could not calculate translation progress!')
total = translation_progress['total']
translated = translation_progress['translated']
if total <= 0:
return _('no translated elements!')
return f'{translated / total:.2%}'
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 type(node.parent) is nodes.section
# index 0: section title node
# index 1: index node
# index 2: target node
and node.parent.index(node) == 2
):
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.domains['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: nodes.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 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
if self.config.smartquotes is False:
# disabled by confval smartquotes
return False
if self.app.builder.name in builders:
# disabled by confval smartquotes_excludes['builders']
return False
if 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']
return any(
tag in smartchars.quotes
for tag in normalize_language_tag(language)
)
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):
# SmartQuotes uses backslash escapes instead of null-escapes
text = re.sub(r'(?<=\x00)([-\\\'".`])', r'\\\1', str(txtnode))
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>.+)[\(\.](?P<section>[1-9]\w*)?\)?)$'
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()),
)
class ReorderConsecutiveTargetAndIndexNodes(SphinxTransform):
"""Index nodes interspersed between target nodes prevent other
Transformations from combining those target nodes,
e.g. ``PropagateTargets``. This transformation reorders them:
Given the following ``document`` as input::
<document>
<target ids="id1" ...>
<index entries="...1...">
<target ids="id2" ...>
<target ids="id3" ...>
<index entries="...2...">
<target ids="id4" ...>
The transformed result will be::
<document>
<index entries="...1...">
<index entries="...2...">
<target ids="id1" ...>
<target ids="id2" ...>
<target ids="id3" ...>
<target ids="id4" ...>
"""
# This transform MUST run before ``PropagateTargets``.
default_priority = 220
def apply(self, **kwargs: Any) -> None:
for target in self.document.findall(nodes.target):
_reorder_index_target_nodes(target)
def _reorder_index_target_nodes(start_node: nodes.target) -> None:
"""Sort target and index nodes.
Find all consecutive target and index nodes starting from ``start_node``,
and move all index nodes to before the first target node.
"""
nodes_to_reorder: list[nodes.target | addnodes.index] = []
# Note that we cannot use 'condition' to filter,
# as we want *consecutive* target & index nodes.
node: nodes.Node
for node in start_node.findall(descend=False, siblings=True):
if isinstance(node, (nodes.target, addnodes.index)):
nodes_to_reorder.append(node)
continue
break # must be a consecutive run of target or index nodes
if len(nodes_to_reorder) < 2:
return # Nothing to reorder
parent = nodes_to_reorder[0].parent
if parent == nodes_to_reorder[-1].parent:
first_idx = parent.index(nodes_to_reorder[0])
last_idx = parent.index(nodes_to_reorder[-1])
if first_idx + len(nodes_to_reorder) - 1 == last_idx:
parent[first_idx:last_idx + 1] = sorted(nodes_to_reorder, key=_sort_key)
def _sort_key(node: nodes.Node) -> int:
# Must be a stable sort.
if isinstance(node, addnodes.index):
return 0
if isinstance(node, nodes.target):
return 1
msg = f'_sort_key called with unexpected node type {type(node)!r}'
raise ValueError(msg)
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)
app.add_transform(ReorderConsecutiveTargetAndIndexNodes)
return {
'version': 'builtin',
'parallel_read_safe': True,
'parallel_write_safe': True,
}
