flake8 linter --ignore settings do not work properly

[Anti-Widdershins]

Issue Type: Bug

In User AND Workspace VSCode Extension Python Configurations set linter to any of the following:
flake8 --extend-ignore=W503,E501
flake8 --extend-ignore=W503 --extend-ignore=E501
flake8 --ignore --extend-ignore=W503 --extend-ignore=E501

Rule E501 is successfully ignored, but W503 is not ignored with any of these options. In fact, flake8 rule W503 is supposed to be ignored by default if --ignore is specified! Are these settings getting to flake8? Why is flake8 plugin not obeying ignore=W503? I am using the latest flake8 install as of a few days ago.

Can anyone help? Thanks.

Extension version: 2020.2.64397
VS Code version: Code 1.42.1 (c47d83b293181d9be64f27ff093689e8e7aed054, 2020-02-11T14:45:59.656Z)
OS version: Windows_NT x64 10.0.18363

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-8650U CPU @ 1.90GHz (8 x 2112)
GPU Status	2d_canvas: enabled flash_3d: enabled flash_stage3d: enabled flash_stage3d_baseline: enabled gpu_compositing: enabled metal: disabled_off multiple_raster_threads: enabled_on oop_rasterization: disabled_off protected_video_decode: enabled rasterization: enabled skia_renderer: disabled_off surface_control: disabled_off surface_synchronization: enabled_on video_decode: enabled viz_display_compositor: enabled_on viz_hit_test_surface_layer: disabled_off webgl: enabled webgl2: enabled
Load (avg)	undefined
Memory (System)	15.93GB (7.23GB free)
Process Argv
Screen Reader	no
VM	0%

[karthiknadig]

@Anti-Widdershins This is an issue with flake8 itself, running it directly in a terminal outside of vscode I get these results, you need to comma separate them like this --extend-ignore=W503,E501

>C:\Python38\python.exe -m flake8 c:\issues\bad_linter.py
c:\issues\bad_linter.py:1:10: E702 multiple statements on one line (semicolon)
c:\issues\bad_linter.py:1:10: E231 missing whitespace after ';'
c:\issues\bad_linter.py:11:1: W391 blank line at end of file


>C:\Python38\python.exe -m flake8 --extend-ignore=E702 --extend-ignore=W391 c:\issues\bad_linter.py
c:\issues\bad_linter.py:1:10: E702 multiple statements on one line (semicolon)
c:\issues\bad_linter.py:1:10: E231 missing whitespace after ';'

>C:\Python38\python.exe -m flake8 --extend-ignore=E702,W391 c:\issues\bad_linter.py
c:\issues\bad_linter.py:1:10: E231 missing whitespace after ';'

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