addnodes.py

"""
    sphinx.addnodes
    ~~~~~~~~~~~~~~~

    Additional docutils nodes.

    :copyright: Copyright 2007-2021 by the Sphinx team, see AUTHORS.
    :license: BSD, see LICENSE for details.
"""

from typing import TYPE_CHECKING, Any, Dict, List, Sequence

from docutils import nodes
from docutils.nodes import Element

if TYPE_CHECKING:
    from sphinx.application import Sphinx


class document(nodes.document):
    """The document root element patched by Sphinx.

    This fixes that document.set_id() does not support a node having multiple node Ids.
    see https://sourceforge.net/p/docutils/patches/167/

    .. important:: This is only for Sphinx internal use.  Please don't use this
                   in your extensions.  It will be removed without deprecation period.
    """

    def set_id(self, node: Element, msgnode: Element = None,
               suggested_prefix: str = '') -> str:
        from sphinx.util import docutils
        if docutils.__version_info__ >= (0, 16):
            ret = super().set_id(node, msgnode, suggested_prefix)  # type: ignore
        else:
            ret = super().set_id(node, msgnode)

        if docutils.__version_info__ < (0, 17):
            # register other node IDs forcedly
            for node_id in node['ids']:
                if node_id not in self.ids:
                    self.ids[node_id] = node

        return ret


class translatable(nodes.Node):
    """Node which supports translation.

    The translation goes forward with following steps:

    1. Preserve original translatable messages
    2. Apply translated messages from message catalog
    3. Extract preserved messages (for gettext builder)

    The translatable nodes MUST preserve original messages.
    And these messages should not be overridden at applying step.
    Because they are used at final step; extraction.
    """

    def preserve_original_messages(self) -> None:
        """Preserve original translatable messages."""
        raise NotImplementedError

    def apply_translated_message(self, original_message: str, translated_message: str) -> None:
        """Apply translated message."""
        raise NotImplementedError

    def extract_original_messages(self) -> Sequence[str]:
        """Extract translation messages.

        :returns: list of extracted messages or messages generator
        """
        raise NotImplementedError


class not_smartquotable:
    """A node which does not support smart-quotes."""
    support_smartquotes = False


class toctree(nodes.General, nodes.Element, translatable):
    """Node for inserting a "TOC tree"."""

    def preserve_original_messages(self) -> None:
        # toctree entries
        rawentries = self.setdefault('rawentries', [])
        for title, docname in self['entries']:
            if title:
                rawentries.append(title)

        # :caption: option
        if self.get('caption'):
            self['rawcaption'] = self['caption']

    def apply_translated_message(self, original_message: str, translated_message: str) -> None:
        # toctree entries
        for i, (title, docname) in enumerate(self['entries']):
            if title == original_message:
                self['entries'][i] = (translated_message, docname)

        # :caption: option
        if self.get('rawcaption') == original_message:
            self['caption'] = translated_message

    def extract_original_messages(self) -> List[str]:
        messages = []  # type: List[str]

        # toctree entries
        messages.extend(self.get('rawentries', []))

        # :caption: option
        if 'rawcaption' in self:
            messages.append(self['rawcaption'])
        return messages


# domain-specific object descriptions (class, function etc.)

class desc(nodes.Admonition, nodes.Element):
    """Node for object descriptions.

    This node is similar to a "definition list" with one definition.  It
    contains one or more ``desc_signature`` and a ``desc_content``.
    """


class desc_signature(nodes.Part, nodes.Inline, nodes.TextElement):
    """Node for object signatures.

    The "term" part of the custom Sphinx definition list.

    As default the signature is a single line signature,
    but set ``is_multiline = True`` to describe a multi-line signature.
    In that case all child nodes must be ``desc_signature_line`` nodes.
    """

    @property
    def child_text_separator(self):
        if self.get('is_multiline'):
            return ' '
        else:
            return super().child_text_separator


class desc_signature_line(nodes.Part, nodes.Inline, nodes.FixedTextElement):
    """Node for a line in a multi-line object signatures.

    It should only be used in a ``desc_signature`` with ``is_multiline`` set.
    Set ``add_permalink = True`` for the line that should get the permalink.
    """
    sphinx_line_type = ''


# nodes to use within a desc_signature or desc_signature_line

class desc_addname(nodes.Part, nodes.Inline, nodes.FixedTextElement):
    """Node for additional name parts (module name, class name)."""


# compatibility alias
desc_classname = desc_addname


class desc_type(nodes.Part, nodes.Inline, nodes.FixedTextElement):
    """Node for return types or object type names."""


class desc_returns(desc_type):
    """Node for a "returns" annotation (a la -> in Python)."""
    def astext(self) -> str:
        return ' -> ' + super().astext()


class desc_name(nodes.Part, nodes.Inline, nodes.FixedTextElement):
    """Node for the main object name."""


class desc_parameterlist(nodes.Part, nodes.Inline, nodes.FixedTextElement):
    """Node for a general parameter list."""
    child_text_separator = ', '

    def astext(self):
        return '({})'.format(super().astext())


class desc_parameter(nodes.Part, nodes.Inline, nodes.FixedTextElement):
    """Node for a single parameter."""


class desc_optional(nodes.Part, nodes.Inline, nodes.FixedTextElement):
    """Node for marking optional parts of the parameter list."""
    child_text_separator = ', '

    def astext(self) -> str:
        return '[' + super().astext() + ']'


class desc_annotation(nodes.Part, nodes.Inline, nodes.FixedTextElement):
    """Node for signature annotations (not Python 3-style annotations)."""


class desc_content(nodes.General, nodes.Element):
    """Node for object description content.

    This is the "definition" part of the custom Sphinx definition list.
    """


class desc_sig_element(nodes.inline):
    """Common parent class of nodes for inline text of a signature."""
    classes = []  # type: List[str]

    def __init__(self, rawsource: str = '', text: str = '',
                 *children: Element, **attributes: Any) -> None:
        super().__init__(rawsource, text, *children, **attributes)
        self['classes'].extend(self.classes)


class desc_sig_name(desc_sig_element):
    """Node for a name in a signature."""
    classes = ["n"]


class desc_sig_operator(desc_sig_element):
    """Node for an operator in a signature."""
    classes = ["o"]


class desc_sig_punctuation(desc_sig_element):
    """Node for a punctuation in a signature."""
    classes = ["p"]


# new admonition-like constructs

class versionmodified(nodes.Admonition, nodes.TextElement):
    """Node for version change entries.

    Currently used for "versionadded", "versionchanged" and "deprecated"
    directives.
    """


class seealso(nodes.Admonition, nodes.Element):
    """Custom "see also" admonition."""


class productionlist(nodes.Admonition, nodes.Element):
    """Node for grammar production lists.

    Contains ``production`` nodes.
    """


class production(nodes.Part, nodes.Inline, nodes.FixedTextElement):
    """Node for a single grammar production rule."""


# other directive-level nodes

class index(nodes.Invisible, nodes.Inline, nodes.TextElement):
    """Node for index entries.

    This node is created by the ``index`` directive and has one attribute,
    ``entries``.  Its value is a list of 5-tuples of ``(entrytype, entryname,
    target, ignored, key)``.

    *entrytype* is one of "single", "pair", "double", "triple".

    *key* is categorization characters (usually a single character) for
    general index page. For the details of this, please see also:
    :rst:dir:`glossary` and issue #2320.
    """


class centered(nodes.Part, nodes.TextElement):
    """Deprecated."""


class acks(nodes.Element):
    """Special node for "acks" lists."""


class hlist(nodes.Element):
    """Node for "horizontal lists", i.e. lists that should be compressed to
    take up less vertical space.
    """


class hlistcol(nodes.Element):
    """Node for one column in a horizontal list."""


class compact_paragraph(nodes.paragraph):
    """Node for a compact paragraph (which never makes a <p> node)."""


class glossary(nodes.Element):
    """Node to insert a glossary."""


class only(nodes.Element):
    """Node for "only" directives (conditional inclusion based on tags)."""


# meta-information nodes

class start_of_file(nodes.Element):
    """Node to mark start of a new file, used in the LaTeX builder only."""


class highlightlang(nodes.Element):
    """Inserted to set the highlight language and line number options for
    subsequent code blocks.
    """


class tabular_col_spec(nodes.Element):
    """Node for specifying tabular columns, used for LaTeX output."""


class meta(nodes.Special, nodes.PreBibliographic, nodes.Element):
    """Node for meta directive -- same as docutils' standard meta node,
    but pickleable.
    """
    rawcontent = None


# inline nodes

class pending_xref(nodes.Inline, nodes.Element):
    """Node for cross-references that cannot be resolved without complete
    information about all documents.

    These nodes are resolved before writing output, in
    BuildEnvironment.resolve_references.
    """


class pending_xref_condition(nodes.Inline, nodes.TextElement):
    """Node for cross-references that are used to choose appropriate
    content of the reference by conditions on the resolving phase.

    When the :py:class:`pending_xref` node contains one or more
    **pending_xref_condition** nodes, the cross-reference resolver
    should choose the content of the reference using defined conditions
    in ``condition`` attribute of each pending_xref_condition nodes::

        <pending_xref refdomain="py" reftarget="io.StringIO ...>
            <pending_xref_condition condition="resolved">
                <literal>
                    StringIO
            <pending_xref_condition condition="*">
                <literal>
                    io.StringIO

    After the processing of cross-reference resolver, one of the content node
    under pending_xref_condition node is chosen by its condition and to be
    removed all of pending_xref_condition nodes::

        # When resolved the cross-reference successfully
        <reference>
            <literal>
                StringIO

        # When resolution is failed
        <reference>
            <literal>
                io.StringIO

    .. note:: This node is only allowed to be placed under pending_xref node.
              It is not allows to place it under other nodes.  In addition,
              pending_xref node must contain only pending_xref_condition
              nodes if it contains one or more pending_xref_condition nodes.

    The pending_xref_condition node should have **condition** attribute.
    Domains can be store their individual conditions into the attribute to
    filter contents on resolving phase.  As a reserved condition name,
    ``condition="*"`` is used for the fallback of resolution failure.
    Additionally, as a recommended condition name, ``condition="resolved"``
    is used for the representation of resolstion success in the intersphinx
    module.

    .. versionadded:: 4.0
    """


class number_reference(nodes.reference):
    """Node for number references, similar to pending_xref."""


class download_reference(nodes.reference):
    """Node for download references, similar to pending_xref."""


class literal_emphasis(nodes.emphasis, not_smartquotable):
    """Node that behaves like `emphasis`, but further text processors are not
    applied (e.g. smartypants for HTML output).
    """


class literal_strong(nodes.strong, not_smartquotable):
    """Node that behaves like `strong`, but further text processors are not
    applied (e.g. smartypants for HTML output).
    """


class manpage(nodes.Inline, nodes.FixedTextElement):
    """Node for references to manpages."""


def setup(app: "Sphinx") -> Dict[str, Any]:
    app.add_node(toctree)
    app.add_node(desc)
    app.add_node(desc_signature)
    app.add_node(desc_signature_line)
    app.add_node(desc_addname)
    app.add_node(desc_type)
    app.add_node(desc_returns)
    app.add_node(desc_name)
    app.add_node(desc_parameterlist)
    app.add_node(desc_parameter)
    app.add_node(desc_optional)
    app.add_node(desc_annotation)
    app.add_node(desc_content)
    app.add_node(desc_sig_name)
    app.add_node(desc_sig_operator)
    app.add_node(desc_sig_punctuation)
    app.add_node(versionmodified)
    app.add_node(seealso)
    app.add_node(productionlist)
    app.add_node(production)
    app.add_node(index)
    app.add_node(centered)
    app.add_node(acks)
    app.add_node(hlist)
    app.add_node(hlistcol)
    app.add_node(compact_paragraph)
    app.add_node(glossary)
    app.add_node(only)
    app.add_node(start_of_file)
    app.add_node(highlightlang)
    app.add_node(tabular_col_spec)
    app.add_node(meta)
    app.add_node(pending_xref)
    app.add_node(number_reference)
    app.add_node(download_reference)
    app.add_node(literal_emphasis)
    app.add_node(literal_strong)
    app.add_node(manpage)

    return {
        'version': 'builtin',
        'parallel_read_safe': True,
        'parallel_write_safe': True,
    }