Test collection hangs forever

[marvingreenberg]

Type: Bug

See also: Issue microsoft/vscode-python#24684. OK, duplicates microsoft/vscode-python#24656

With the attached project, opening the Testing tab hangs forever on collection. Removing the two test files test_utils1.py and test_utils2.py and restarting vscode, test collectiojn succeeds. It seems having only a single test file succeeds. Creating a simple example was difficult - removing parts of the source code or simplifying the tests sometimes would fix the infinite hang.

The python logs seem to correctly show the test collection output, but the pipe output is not read. Once the test collection hangs, the only way to reset is by completely restarting vscode. Clicking "stop collection" has not effect.

Running test collection on the command line succeeds.

$ python -m venv .venv
$ . .venv/bin/activate
$ pip install -e '.[dev]'
$ pytest --collect-only -vv --no-cov tests

<reports 20 tests>

Extension version: 2024.12.1
VS Code version: Code 1.96.2 (fabdb6a30b49f79a7aba0f2ad9df9b399473380f, 2024-12-19T10:22:47.216Z)
OS version: Darwin arm64 23.6.0
Modes:

System Info

Item	Value
CPUs	Apple M1 Max (10 x 2400)
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 webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	2, 2, 3
Memory (System)	64.00GB (11.22GB free)
Process Argv	--crash-reporter-id 162a7914-1a53-4983-8814-9812ca819d4c
Screen Reader	no
VM	0%

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[marvingreenberg]

This project exhibits the behavior for me. hanging-test-collection.tgz

[marvingreenberg]

Duplicates microsoft/vscode-python#24656