Types not explicitly exported from package

[johnthagen]

The following code:

from parsita import Success

Raises the following error from Mypy when run in strict mode:

main.py:1: error: Module "parsita" does not explicitly export attribute "Success"  [attr-defined]

I believe this is because there is no __all__ defined in

• https://github.com/drhagen/parsita/blob/master/src/parsita/__init__.py

This also applies to other types re-exported from the base parsita package, such as Parser, Result, etc.

Environment

• Python 3.11
• parsita 2.2.0
• mypy 1.13.0

[tool.mypy]
strict = true

Related to

• Support Mypy Type Checking #37
• Run mypy #115

[drhagen]

If there is a solution to this that is not "Relist everything in all", I'll do it. Otherwise, I am going to follow other projects and declare this WONTFIX.

[drhagen]

Ruff has a similar lint, but I globally disable it. However, I don't see any evidence that such a targeted disable is available. It looks like MyPy+Parsita users putting in no_implicit_reexport = False is the narrowest fix.

[johnthagen]

If there is a solution to this that is not "Relist everything in __all__"

It looks like you can also signal the intention to re-export by

from .state import (
    Failure as Failure

There is still duplication, but at least it's localized?

• Example: https://github.com/psycopg/psycopg/pull/44/files

[johnthagen]

I am going to follow other projects and declare this WONTFIX.

One of the referenced projects, click, actually did reverse their decision and make the change

• Update typing pallets/click#1887

I agree this is not optimal and it would be nice if Mypy had a way to opt out of this feature only for a particular dependency, but turning off this check for an entire application also has other downsides in that you then can accidentally import things from the wrong location in your own codebase.

[johnthagen]

Related Ruff request

• Idea: warn when a re-exported name is imported astral-sh/ruff#13507