[pyright] `DataFrame.columns` becomes `Never` by `pyright` after assignment and `raise` in loop

[cmp0xff]

Describe the bug

After an assignment and a raise in a loop, DataFrame.columns becomes Never by pyright. See the minimal example below.

It is likely a pyright bug, but I can't make an example that is independent of pandas and pandas-stubs.

To Reproduce

Provide a minimal runnable pandas example that is not properly checked by the stubs.

from typing_extensions import reveal_type
import pandas as pd

df = pd.DataFrame()

df.columns = [str(c).upper() for c in df.columns]

reveal_type(df.columns)  # Index[str], fine

for _ in ():
    if "1" in df.columns:
        raise

reveal_type(df.columns)  # Never

Indicate which type checker you are using

pyright. mypy does not have this problem.

Show the error message received from that type checker while checking your example

ttest.py
  ttest.py:8:13 - information: Type of "df.columns" is "Index[str]"
  ttest.py:14:13 - information: Type of "df.columns" is "Never"
0 errors, 0 warnings, 2 informations

Please complete the following information

• OS: Windows
• OS Version: 11
• python version: 3.10.11
• version of type checker:
• version of installed pandas-stubs: main, b4c3b56

[Dr-Irv]

Reproduced it: microsoft/pyright#11178