code is shown as disabled after pd.concat([]) call

[akosmaroy]

Type: Bug

Create a code that contains a pd.concat([]) like the following:

import pandas as pd

def foo(df, dff):
    for i in range(10):
        df = pd.concat([df, dff])
        # this is reachable code and should not be disabled
        # or shown in grey
        df['foo'] = 'foo'
        # but it is shown in grey, the line below too
        df['bar'] = 'bar'

    return df

foo()

if Pylance is enabled, the rows after pd.concat([]) are shown as disabled (grayed out). If Pylance is disabled, they are shown with proper highlight.

Extension version: 2024.3.1
VS Code version: Code 1.87.2 (863d2581ecda6849923a2118d93a088b0745d9d6, 2024-03-08T15:20:17.278Z)
OS version: Windows_NT x64 10.0.22631
Modes:
Connection to 'wsl+ubuntu' could not be established

System Info

Item	Value
CPUs	AMD Ryzen 9 5950X 16-Core Processor (32 x 3394)
GPU Status	2d_canvas: enabled canvas_oop_rasterization: enabled_on direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: disabled_off video_decode: enabled video_encode: enabled vulkan: disabled_off webgl: enabled webgl2: enabled webgpu: enabled
Load (avg)	undefined
Memory (System)	63.91GB (35.94GB free)
Process Argv	--crash-reporter-id 0b37d44c-c01e-46d2-8e4f-655177a1dd2c
Screen Reader	no
VM	0%

Connection to 'wsl+ubuntu' could not be established

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[akosmaroy]

[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