Python 3.13 new `__firstlineno__` class attribute

[koutoftimer]

python/cpython#118465 introduces new class attribute __firstlineno__, which pyright doesn't support.

An example code work fine in python3.13 runtime

class A: ...


print(f"{A.__firstlineno__=}")

but pyright shows an error

:!pyright run.py                                                                                         
                                                                                                         
/tmp/tmp.A9F2mvqmhp/run.py                                                                               
  /tmp/tmp.A9F2mvqmhp/run.py:4:12 - error: Cannot access attribute "__firstlineno__" for class "type[A]" 
    Attribute "__firstlineno__" is unknown (reportAttributeAccessIssue)                                  
1 error, 0 warnings, 0 informations

I've been using pyright 1.1.389 via neovim/mason/pyright extension.

:!pyright --version                                                                                                                                                                                                
                                                                                                                                                                                                                   
pyright 1.1.389

[erictraut]

Pyright doesn't have hard-coded knowledge of symbols like this. If you'd like to see this supported, it would need to be added to the typeshed stdlib stubs, which are used by all Python type checkers including pyright. Feel free to submit a feature request or PR to typeshed.