Python skip all Tests

[lorenzo-racca15]

Type: Bug

Behaviour

When I start the tests from the UI sidebar all unittests go to "skipped" state

Steps to reproduce:

1. Create an unittest class
2. Write some test method
3. Try to run some test from the UI.

The bug happen in the sidebar but also directly on the "start test" button in the editor

Diagnostic data

Output for Python in the Output panel (View→Output, change the drop-down the upper-right of the Output panel to Python)

2026-03-30 09:05:34.109 [info] Running unittest with arguments: /root/.vscode-server/extensions/ms-python.python-2026.4.0-linux-x64/python_files/unittestadapter/execution.py --udiscovery -v -s src/tests -t src -p test_*.py for workspace /workspaces/codebase-api 

2026-03-30 09:05:34.373 [info] Test Result named pipe /tmp/python-test-results-89b63f29f67a8271ccfe  cancelled
2026-03-30 09:05:34.373 [info] [test-by-project] All project executions completed

Extension version: 2026.0.0
VS Code version: Code 1.113.0 (cfbea10c5ffb233ea9177d34726e6056e89913dc, 2026-03-24T15:07:18+01:00)
OS version: Windows_NT x64 10.0.26200
Modes:
Remote OS version: Linux x64 5.15.153.1-microsoft-standard-WSL2
Remote OS version: Linux x64 5.15.153.1-microsoft-standard-WSL2
Remote OS version: Linux x64 5.15.153.1-microsoft-standard-WSL2

• Python version (& distribution if applicable, e.g. Anaconda): 3.12.11.final.0
• Type of virtual environment used (e.g. conda, venv, virtualenv, etc.): System
• Value of the python.languageServer setting: Pylance

User Settings

languageServer: "Pylance"

testing
• unittestArgs: "<placeholder>"
• unittestEnabled: true

Installed Extensions

Extension Name	Extension Id	Version
copilot-chat	Git	0.41.2
debugpy	ms-	2025.18.0
js-debug	ms-	1.112.0
mypy-type-checker	ms-	2025.2.0
python	ms-	2026.4.0
rest-client	hum	0.25.1
ruff	cha	2026.38.0
sonarlint-vscode	Son	4.45.0
todo-tree	Gru	0.0.226
vscode-js-profile-table	ms-	1.0.10
vscode-pylance	ms-	2026.1.1
vscode-python-envs	ms-	1.24.0

System Info

Item	Value
CPUs	11th Gen Intel(R) Core(TM) i7-1165G7 @ 2.80GHz (8 x 2803)
GPU Status	2d_canvas: enabled GPU0: VENDOR= 0x8086, DEVICE=0x9a49 [Intel(R) Iris(R) Xe Graphics], DRIVER_VENDOR=Intel, DRIVER_VERSION=32.0.101.7084 ACTIVE GPU1: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.26100.7309 Machine model name: Machine model version: 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 trees_in_viz: disabled_off video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	undefined
Memory (System)	23.69GB (4.18GB free)
Process Argv	--crash-reporter-id 38cb5619-31a0-494c-b008-97a02ea21732
Screen Reader	no
VM	0%

Item	Value
Remote	Dev Container: ai-api @ desktop-linux
OS	Linux x64 5.15.153.1-microsoft-standard-WSL2
CPUs	11th Gen Intel(R) Core(TM) i7-1165G7 @ 2.80GHz (4 x 0)
Memory (System)	11.53GB (3.83GB free)
VM	0%

Item	Value
Remote	Dev Container: codebase-api @ desktop-linux
OS	Linux x64 5.15.153.1-microsoft-standard-WSL2
CPUs	11th Gen Intel(R) Core(TM) i7-1165G7 @ 2.80GHz (4 x 0)
Memory (System)	11.53GB (3.83GB free)
VM	0%

Item	Value
Remote	Dev Container: codex-sdk @ desktop-linux
OS	Linux x64 5.15.153.1-microsoft-standard-WSL2
CPUs	11th Gen Intel(R) Core(TM) i7-1165G7 @ 2.80GHz (4 x 0)
Memory (System)	11.53GB (3.83GB free)
VM	0%

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