Sphinx: Function/class signatures fail with Py3 style annotations and typing.TYPE_CHECKING

[tuomas2]

Problem and how to reproduce

Function/class signatures do not work properly when using Py3 style annotations, and type definitions are conditionally imported using typing.TYPE_CHECKING.

Minimal example:

import typing

if typing.TYPE_CHECKING:
    from .session import Session


class Test:
    def __init__(self, param: 'Session') -> None:
        pass

I use autodoc to write documentation about Test class in my index.rst:

.. autoclass:: mytest.test.Test
   :members:

This causes the following error

..../classes.rst:4: WARNING: error while formatting arguments for ...test.Test: name 'Session' is not defined

Documentation does not display class initialization signature (nor any other function/method possible signatures) at all.

Expected results

Documentation displays class and its signatures properly.

Environment info

• OS: Linux
• Python version: 3.6
• Sphinx version: 1.5.3

[libre-man]

What is the current status of this issue? The problem is that with typing you can do special imports, if typing.TYPE_CHECKING and import modules you only need for type checking to avoid circular imports and sphinx is not importing those modules.

[lbenezriravin]

Is there an update on this issue? Does anyone have a workaround until a fix is merged? _{other than removing type hints}

As always, big thank you to the maintainers for an incredible tool.

[tk0miya]

It seems the latest Sphinx (v3.1.2) does not raise any warnings on building document using the reported code. I don't know which release fixed this.
Anyway, this issue was already resolved. Now I'm closing this.
Please file a new issue if you still have the same error.