2.8.0 causes pyright to report type incompatibility errors

[lgfang]

After upgrading from version 2.7.1 to 2.8.0, Pyright started reporting the following error :

$ pyright test
...
"CliSettingsSource[MyOptions]" is not assignable to "CliSettingsSource[object]"
Type parameter "T@CliSettingsSource" is invariant, but "MyOptions" is not the same as "object" (reportAssignmentType)
...
I believe this issue is caused by a commit that changed _cli_settings_source from CliSettingsSource[Any]|None to CliSettingsSource[object]|None.

I attempted to resolve the problem by defining T as a covariant type variable in sources.py. While this adjustment satisfied Pyright, it resulted in a mypy failure (#554):

Mypy.....................................................................Failed
- hook id: mypy
- exit code: 2

mypy pydantic_settings
pydantic_settings/sources.py:1632: error: Cannot use a covariant type variable as a parameter [misc]
Found 1 error in 1 file (checked 5 source files)
make: *** [mypy] Error 1

Steps to Reproduce:

Run pyright test.py with the following content:

#!/usr/bin/env python
from pydantic_settings import BaseSettings, EnvSettingsSource, CliSettingsSource
class OptionsBase:
    pass
class MyOptions(OptionsBase):
    pass
cli_source: CliSettingsSource[object] = CliSettingsSource[MyOptions](BaseSettings)

Please let me know if further information is needed.

[hramezani]

Thanks @lgfang for reporting this issue.

We fixed the problem and release pydantic-settings 2.8.1