failing `pytest` tests are marked as “success” when some of the subtests succeeded

[flying-sheep]

Type: Bug

Behaviour

See title, see #24455

what I expect instead

test_subtests should be marked as failed as the CLI shows (pytest itself isn’t buggy and shows things as expected):

Steps to reproduce:

def test_subtests(subtests):
    with subtests.test("success"):
        assert True
    with subtests.test("failure"):
        pytest.fail("subtest failure")

1. install pytest >=9
2. run the above test in the test sidebar
3. see buggy results as described and shown above

Diagnostic data

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

2026-02-28 11:47:00.075 [info] Attempting to use temp directory for test ids file, file name: test-ids-c9c0405040b5fbf605e6.txt
2026-02-28 11:47:00.084 [info] Environment variables set for pytest execution: PYTHONPATH=/home/phil/.vscode/extensions/ms-python.python-2026.2.0-linux-x64/python_files, TEST_RUN_PIPE=/run/user/1000/python-test-results-31b84a1d4f7f94f5a051, RUN_TEST_IDS_PIPE=/run/user/1000/test-ids-c9c0405040b5fbf605e6.txt
2026-02-28 11:47:00.084 [info] Running pytest with arguments: /home/phil/.vscode/extensions/ms-python.python-2026.2.0-linux-x64/python_files/vscode_pytest/run_pytest_script.py for workspace /home/phil/Dev/Python/test
2026-02-28 11:47:00.084 [info] > …/python ~/.vscode/extensions/ms-python.python-2026.2.0-linux-x64/python_files/vscode_pytest/run_pytest_script.py
2026-02-28 11:47:00.084 [info] cwd: .
2026-02-28 11:47:03.400 [info] Test Result named pipe /run/user/1000/python-test-results-31b84a1d4f7f94f5a051  cancelled

Extension version: 2026.2.0
VS Code version: Code 1.109.5 (072586267e68ece9a47aa43f8c108e0dcbf44622, 2026-02-19T19:43:32.382Z)
OS version: Linux x64 6.18.13-arch1-1
Modes:

• Python version (& distribution if applicable, e.g. Anaconda): 3.14.3
• Type of virtual environment used (e.g. conda, venv, virtualenv, etc.): Hatch
• Value of the python.languageServer setting: Pylance

User Settings

languageServer: "Pylance"

testing
• pytestArgs: "-vv"
• pytestEnabled: true

experiments
• optInto: ["pythonTestAdapter"]

Installed Extensions

Extension Name	Extension Id	Version
2077-theme	End	1.5.3
biome	bio	3.4.1
cmake-tools	ms-	1.22.28
code-spell-checker	str	4.5.6
code-spell-checker-german	str	2.3.4
codeium	Cod	1.48.2
cpp-devtools	ms-	0.2.0
datawrangler	ms-	1.24.0
debugpy	ms-	2025.18.0
dependi	fil	0.7.21
EditorConfig	Edi	0.18.1
editorconfiggenerator	nep	0.2.1
errorlens	use	3.28.0
even-better-toml	tam	0.21.2
gc-excelviewer	Gra	4.2.64
git-graph	mhu	1.30.0
jinjahtml	sam	0.20.0
js-debug	ms-	1.105.0
js-debug-companion	ms-	1.1.3
jupyter	ms-	2025.9.1
jupyter-keymap	ms-	1.1.2
jupyter-renderers	ms-	1.3.2025062701
live-server	ms-	0.4.17
markdown-checkbox	bie	0.4.0
markdown-mermaid	bie	1.32.0
myst-highlight	Exe	0.11.0
myst-tml-syntax	chr	0.1.3
pdf	tom	1.2.2
pre-commit-vscode	Mar	0.1.0
python	ms-	2026.2.0
rainbow-csv	mec	3.24.1
remote-containers	ms-	0.442.0
remote-explorer	ms-	0.5.0
remote-ssh	ms-	0.122.0
remote-ssh-edit	ms-	0.87.0
ruff	cha	2026.36.0
RunOnSave	eme	1.0.3
shades-of-purple	ahm	7.3.6
simple-rst	tro	1.5.4
simply-view-image-for-python-debugging	ela	4.0.10
string-converter	ada	0.1.2
synthwave-vscode	Rob	0.1.20
test-adapter-converter	ms-	0.2.1
todo-tree	Gru	0.0.226
toml	be5	0.6.0
vscode-ansi	ili	1.1.7
vscode-dask	joy	0.0.4
vscode-github-actions	git	0.31.0
vscode-graphql	Gra	0.13.2
vscode-graphql-syntax	Gra	1.3.8
vscode-js-profile-table	ms-	1.0.10
vscode-jupyter-cell-tags	ms-	0.1.9
vscode-jupyter-slideshow	ms-	0.1.6
vscode-language-pack-de	MS-	1.108.2026021109
vscode-mogami	nin	0.1.9
vscode-nushell-lang	The	1.10.0
vscode-open	san	0.3.0
vscode-pull-request-github	Git	0.128.0
vscode-pylance	ms-	2026.1.100
vscode-svg-previewer	vit	0.7.0
vscode-yaml	red	1.21.0
vscode-zipfs	arc	3.0.0
xml	Dot	2.5.1

System Info

Item	Value
CPUs	AMD Ryzen 7 3700X 8-Core Processor (16 x 3379)
GPU Status	2d_canvas: enabled GPU0: VENDOR= 0x1002 [Google Inc. (AMD)], DEVICE=0x73bf [ANGLE (AMD, AMD Radeon RX 6800 XT (radeonsi navi21 ACO), OpenGL ES 3.2 Mesa 26.0.1-arch1.1)], DRIVER_VENDOR=Mesa, DRIVER_VERSION=26.0.1 ACTIVE 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: disabled_software vulkan: disabled_off webgl: enabled webgl2: enabled webgpu: disabled_off webnn: disabled_off
Load (avg)	3, 2, 2
Memory (System)	31.26GB (19.68GB free)
Process Argv	--crash-reporter-id e73710ca-22af-43b0-a2f6-ea09b8305a53
Screen Reader	no
VM	0%
DESKTOP_SESSION	plasma
XDG_CURRENT_DESKTOP	KDE
XDG_SESSION_DESKTOP	KDE
XDG_SESSION_TYPE	wayland

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copilot_t_ci:31333650
e5gg6876:31282496
pythonrdcb7:31342333
6518g693:31463988
aj953862:31281341
6abeh943:31336334
envsactivate1:31464700
cloudbuttont:31379625
3efgi100_wstrepl:31403338
use-responses-api:31390855
je187915:31454425
ec5jj548:31422691
cp_cls_t_966_ss:31454198
4je02754:31466945
find_all_ref_in_bg_f:31469307
a5gib710:31434435
38bie571_auto:31426784
7a04d226_do_not_restore_last_panel_session:31438103
cp_cls_t_1081:31454832
a43f0574a:31442826
e9c30283:31461165
idci7584:31464702
edit_mode_hidden:31461530
3bj34942:31461205
864ei723_large_tool_results_to_disk:31460878
7ef87755:31458076
chat:31457767