Enabling FormatOnSave with Black makes saving files impossible

[tomkcook]

Type: Bug

Open workspace settings and enable "FormatOnSave".

Open a Python file and configure Black as the default formatter.

Make a change and attempt to save the file.

Every time I try to save a file, VScode pops up a note that the file has changed on disk and do I really want to overwrite the change?

This only affects Python files formatted with Black. I assume the Black formatter is being run on the file in the background before saving the file and this results in the file being changed on disk, which VScode then fails to reload correctly.

Extension version: 1.0.3 VS Code version: Code 1.86.1 (31c37ee8f63491495ac49e43b8544550fbae4533, 2024-02-07T09:07:19.849Z) OS version: Linux x64 6.6.10-060610-generic Modes:

System Info

|Item|Value| |---|---| |CPUs|13th Gen Intel(R) Core(TM) i9-13900HX (32 x 3205)| |GPU Status|2d_canvas: enabled
canvas_oop_rasterization: disabled_off
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: disabled_software
vulkan: disabled_off
webgl: enabled
webgl2: enabled
webgpu: disabled_off| |Load (avg)|1, 1, 1| |Memory (System)|31.15GB (11.25GB free)| |Process Argv|. --crash-reporter-id b8a9e683-f4ee-415b-9c94-a32686cb170e| |Screen Reader|no| |VM|0%| |DESKTOP_SESSION|gnome| |XDG_CURRENT_DESKTOP|GNOME| |XDG_SESSION_DESKTOP|gnome| |XDG_SESSION_TYPE|x11|

A/B Experiments

``` vsliv368:30146709 vspor879:30202332 vspor708:30202333 vspor363:30204092 vstes627:30244334 vscod805cf:30301675 binariesv615:30325510 vsaa593cf:30376535 py29gd2263:30899288 vscaac:30438847 c4g48928:30535728 azure-dev_surveyone:30548225 962ge761:30959799 pythongtdpath:30769146 welcomedialogc:30910334 pythonidxpt:30866567 pythonnoceb:30805159 asynctok:30898717 pythontestfixt:30902429 pythonregdiag2:30936856 pyreplss1:30897532 pythonmypyd1:30879173 pythoncet0:30885854 pythontbext0:30879054 dsvsc016:30899300 dsvsc017:30899301 dsvsc018:30899302 pydisww2:30959801 7j2b6412:30962116 bg6jg535:30958357 ```

[34j]

Please consider using Auto Save instead of Format On Save. This extension sells the simplicity of calling black in the CLI. You should also consider using Microsoft's extension, which goes more into the internals of VS Code, which seems to be required to resolve this issue. Thanks for your report anyway. (BTW, what is A/B Experiments? It looks cool.)