"""Test the non-trivial features in the :mod:`sphinx.addnodes` module."""

from __future__ import annotations

from typing import TYPE_CHECKING

import pytest

from sphinx import addnodes

if TYPE_CHECKING:

from collections.abc import Iterator

@pytest.fixture

def sig_elements() -> Iterator[set[type[addnodes.desc_sig_element]]]:

"""Fixture returning the current ``addnodes.SIG_ELEMENTS`` set."""

original = addnodes.SIG_ELEMENTS.copy() # safe copy of the current nodes

yield {*addnodes.SIG_ELEMENTS} # temporary value to use during tests

addnodes.SIG_ELEMENTS = original # restore the previous value

def test_desc_sig_element_nodes(

sig_elements: set[type[addnodes.desc_sig_element]],

) -> None:

"""Test the registration of ``desc_sig_element`` subclasses."""

# expected desc_sig_* node classes (must be declared *after* reloading

# the module since otherwise the objects are not the correct ones)

EXPECTED_SIG_ELEMENTS = {

addnodes.desc_sig_space,

addnodes.desc_sig_name,

addnodes.desc_sig_operator,

addnodes.desc_sig_punctuation,

addnodes.desc_sig_keyword,

addnodes.desc_sig_keyword_type,

addnodes.desc_sig_literal_number,

addnodes.desc_sig_literal_string,

addnodes.desc_sig_literal_char,

}

assert addnodes.SIG_ELEMENTS == EXPECTED_SIG_ELEMENTS

# create a built-in custom desc_sig_element (added to SIG_ELEMENTS)

class BuiltInSigElementLikeNode(addnodes.desc_sig_element, _sig_element=True):

pass

# create a custom desc_sig_element (implicitly not added to SIG_ELEMENTS)

class Custom1SigElementLikeNode(addnodes.desc_sig_element):

pass

# create a custom desc_sig_element (explicitly not added to SIG_ELEMENTS)

class Custom2SigElementLikeNode(addnodes.desc_sig_element, _sig_element=False):

pass

assert BuiltInSigElementLikeNode in addnodes.SIG_ELEMENTS

assert Custom1SigElementLikeNode not in addnodes.SIG_ELEMENTS

assert Custom2SigElementLikeNode not in addnodes.SIG_ELEMENTS