code incorrectly marked as unreachable

[bryjohnston]

python 3.11.4
pylance v2024.3.1
pandas 2.2.1
vscode 1.87.2 windows 10

Since the latest pylance update, I have found large portions of code being marked as unreachable when they definitely are not.
I don't know for sure that this is a pandas issue, but that was the easiest way I could reproduce the error. In the following code (meaningless, just to demonstrate), the print statement is marked as unreachable by pylance following a use of the pandas function:

import pandas as pd

df1 = pd.DataFrame()
df2 = pd.DataFrame()


def testfxn(df1, df2):
    for a in range(5):
        test = pd.concat([df1, df2], axis=1)
        print('hi!')

testfxn(df1, df2)

[debonte]

This is a duplicate of #5630. The underlying issue was in pandas-stubs. They have fixed it and their fix shipped in our 2024.3.101 prerelease build.

Our wiki has instructions on how to switch to prerelease if you need them: https://github.com/microsoft/pylance-release/wiki/FAQ#how-to-switch-pylance-builds

[debonte]

This issue is also fixed in our most recent stable release -- 2024.3.2