Type annotations which contain commas in autosummary table are not removed completely

[greyli]

Describe the bug

Here is an example in marshmallow docs: https://marshmallow.readthedocs.io/en/stable/marshmallow.validate.html

Take the first And class as an example. Here is the raw definition:

And(*validators: Callable[[Any], Any], error: Optional[str] = None)

Expected output:

And(*validators, error)

Actual output:

And(*validators, Any], error)

It seems that Sphinx uses the comma to separate the arguments, but it can't tell if the comma is in the arguments list or in the type annotations.

How to Reproduce

$ git clone https://github.com/marshmallow-code/marshmallow
$ cd marshmallow
$ pip install tox
$ tox -e docs
$ # open _build/html/marshmallow.validate.html

Expected behavior

No response

Your project

https://github.com/marshmallow-code/marshmallow

Screenshots

Source: https://github.com/marshmallow-code/marshmallow/blob/dev/docs/marshmallow.validate.rst
Doc: https://marshmallow.readthedocs.io/en/stable/marshmallow.validate.html

OS

macOS Big Sur 11.4

Python version

3.8

Sphinx version

4.1.2

Sphinx extensions

No response

Extra tools

No response

Additional context

No response