details.py

from docutils import nodes
from docutils.parsers.rst import Directive, directives, states
from docutils.parsers.rst.roles import set_classes


class details(nodes.General, nodes.Element):
    pass


class summary(nodes.General, nodes.Element):
    pass


def visit_details_node(self, node):
    self.body.append(self.starttag(node, "details", CLASS=node.attributes.get("class", "")))


def visit_summary_node(self, node):
    self.body.append(self.starttag(node, "summary", CLASS=node.attributes.get("summary-class", "")))
    self.body.append(node.rawsource)


def depart_details_node(self, node):
    self.body.append("</details>\n")


def depart_summary_node(self, node):
    self.body.append("</summary>")


class DetailsDirective(Directive):
    final_argument_whitespace = True
    optional_arguments = 1

    option_spec = {
        "class": directives.class_option,
        "summary-class": directives.class_option,
    }

    has_content = True

    def run(self):
        set_classes(self.options)
        self.assert_has_content()

        text = "\n".join(self.content)
        node = details(text, **self.options)

        if self.arguments:
            summary_node = summary(self.arguments[0], **self.options)
            (
                summary_node.source,
                summary_node.line,
            ) = self.state_machine.get_source_and_line(self.lineno)
            node += summary_node

        self.state.nested_parse(self.content, self.content_offset, node)
        return [node]


def setup(app):
    app.add_node(details, html=(visit_details_node, depart_details_node))
    app.add_node(summary, html=(visit_summary_node, depart_summary_node))
    app.add_directive("details", DetailsDirective)