Latest version seems to break mypy

[mehdigmira]

when running mypy on my project, I get this error:
Error importing plugin sqlmypy

When debugging a little bit, the problem seems to be here:

    def get_dynamic_class_hook(self, fullname: str) -> CB[DynamicClassDefContext]:
  File "/usr/lib/python3.5/typing.py", line 546, in __getitem__
    "Cannot subscript an existing Union. Use Union[u, t] instead.")
TypeError: Cannot subscript an existing Union. Use Union[u, t] instead.

[ilevkivskyi]

You need to update Python to a newer version (I think at least 3.5.2, but better just the latest 3.5 version).

[arusahni]

I have this same error on Python 3.7.2:

$ python --version
Python 3.7.2

$ mypy --version
mypy 0.670

$ pip show sqlalchemy-stubs
Name: sqlalchemy-stubs
Version: 0.1
Summary: SQLAlchemy stubs and mypy plugin
Home-page: https://github.com/dropbox/sqlalchemy-stubs
Author: Ivan Levkivskyi
Author-email: levkivskyi@gmail.com
License: MIT License
Location: /Users/aru/.virtualenvs/portal/lib/python3.7/site-packages
Requires: typing-extensions, mypy
Required-by:

In my setup.cfg:

[mypy]
plugins = sqlmypy

[ilevkivskyi]

You can't have the same error on Python 3.7.2 because that line of code simply doesn't exist in Python 3.7.2, can you post exactly the traceback you see?

[arusahni]

I'm sorry, I don't know how I missed the traceback portion of the OP's error. I seem to be unable to generate a traceback?

$ mypy --tb package_name
setup.cfg:8: error: Error importing plugin 'sqlmypy'

[ilevkivskyi]

Do you have sqlalchemy-stubs and mypy installed in the same virtualenv?

[arusahni]

I do... however, I discovered that, for whatever reason, my shell was using my global mypy. Forcing a re-hash fixed things. Sorry for the confusion!

[cdpath]

I fixed this issue by adding sqlalchemy-stubs explicitly in .pre-commit-config.yaml, like this:

-   repo: https://github.com/pre-commit/mirrors-mypy
    rev: 'v0.910'
    hooks:
    - id: mypy
      additional_dependencies:
        - 'pydantic'
        - 'sqlalchemy-stubs'