Alias type warning when declare in function param or return type

[jgraulle]

I have understood from #414 the alias type are supported from sphinx-autoapi 3.6.0.

When I tried to use an alias type as a param or a return type, when a build the documentation I get the message WARNING: py:class reference target not found: MyAlias[ref.class]. I have tried with the sphinx-autoapi 3.6.0 and 3.6.1 version.

Maybe is not a sphinx-autoapi issue but more low level, and maybe I have made a mistake when configure my project.

I have:

• requirements.txt

Sphinx==8.2.3
sphinx-autoapi==3.6.1

• docs/conf.py

project = 'sphinx_test'
copyright = 'None'
author = 'None'
extensions = ['autoapi.extension']
autoapi_type = 'python'
autoapi_dirs = ['../src']
autoapi_keep_files = True

• docs/index.rst

.. toctree::
   :maxdepth: 1

   autoapi/index

• src/module.py

"""A module"""

import typing


class MyClass:
    """A class"""
    pass

MyAliasAsSimpleVariableAssignments = str | int
"""An alias with simple variable assignments"""

MyAliasAsTypeAlias: typing.TypeAlias = float | None
"""An alias with TypeAlias"""

type MyAliasAsType = str | int
"""An alias with type"""

MyAliasAsTypeVar = typing.TypeVar("MyAliasAsTypeVar", bool, bytes)
"""An alias with type var"""

def functionClass(param: MyClass) -> MyClass:
    """
    - :py:class:`MyClass` is OK
    - :py:type:`MyClass` is OK
    - Param and return function link are OK
    """
    return MyClass()

def functionAliasAsSimpleVariableAssignments(param: MyAliasAsSimpleVariableAssignments) \
        -> MyAliasAsSimpleVariableAssignments:
    """
    - :py:class:`MyAliasAsSimpleVariableAssignments` is OK
    - :py:type:`MyAliasAsSimpleVariableAssignments` is OK
    - Param and return function link are KO
    """
    return "TODO"

def functionAliasAsTypeAlias(param: MyAliasAsTypeAlias) -> MyAliasAsTypeAlias:
    """
    - :py:class:`MyAliasAsTypeAlias` is OK
    - :py:type:`MyAliasAsTypeAlias` is OK
    - Param and return function link are KO
    """
    return "TODO"

def functionAliasAsType(param: MyAliasAsType) -> MyAliasAsType:
    """
    - :py:class:`MyAliasAsType` is OK
    - :py:type:`MyAliasAsType` is OK
    - Param and return function link are KO
    """
    return "TODO"

def functionAliasAsTypeVar(param: MyAliasAsTypeVar) -> MyAliasAsTypeVar:
    """
    - :py:class:`MyAliasAsTypeVar` is OK
    - :py:type:`MyAliasAsTypeVar` is OK
    - Param and return function link are KO
    """
    return "TODO"

When I run sphinx-build -M html docs build --nitpicky I get some warnings:

.../docs/autoapi/module/index.rst:34: WARNING: py:class reference target not found: MyAliasAsSimpleVariableAssignments [ref.class]
.../docs/autoapi/module/index.rst:41: WARNING: py:class reference target not found: MyAliasAsTypeAlias [ref.class]
.../docs/autoapi/module/index.rst:48: WARNING: py:class reference target not found: MyAliasAsType [ref.class]
.../docs/autoapi/module/index.rst:55: WARNING: py:class reference target not found: MyAliasAsTypeVar [ref.class]

And in the generated HTML documentation some links are ok and some ok (see comment in src/module.py)

I have tried some workaround like several ways to declare a alias, use from __future__ import annotations with autodoc_type_aliases, but I did not managed to make it work.

Is it a problem with my workspace ? Is it a new issue ?

The full zip of this example pythonSphinxAlias.zip