[Python] VS Code / Python / Debugging pytest Test with the Debugger

How can I get VS Code to put me into the debugger at the point of failure when running tests with pytest?

Pytest catches all errors and asserts, and VS code invokes the debugger only on uncaught errors (I can change this to raised exception, but then it stops on everything raised under a try).

I tried to set --pdb as pytest argument, but this leads to errors:

============================= test session starts =============================
platform win32 -- Python 3.8.1, pytest-5.3.2, py-1.8.1, pluggy-0.13.1
rootdir: c:\Projects\debugtest, inifile: pytest.ini
collected 1 item

test.py F
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> traceback >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Traceback (most recent call last):
File "C:\Projects\debugtest\test.py", line 4, in test_with_assert
assert 42==2.71828
AssertionError: assert 42 == 2.71828
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> entering PDB >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

>>>>>>>>>>>>>>>>>> PDB post_mortem (IO-capturing turned off) >>>>>>>>>>>>>>>>>>
> c:\projects\debugtest\test.py(4)test_with_assert()
-> assert 42==2.71828
(Pdb)

PYDEV DEBUGGER WARNING:
sys.settrace() should not be used when the debugger is being used.
This may cause the debugger to stop working correctly.
If this is needed, please check:
http://pydev.blogspot.com/2007/06/why-cant-pydev-debugger-work-with.html
to see how to restore the debug tracing back correctly.
Call Location:
File "C:\Program Files\Python38\lib\bdb.py", line 359, in set_quit
sys.settrace(None)


- generated xml file: C:\Users\tzhgfma1\AppData\Local\Temp\tmp-24044mEWMyB1nPYAu.xml -
!!!!!!!!!!!!!!!!!! _pytest.outcomes.Exit: Quitting debugger !!!!!!!!!!!!!!!!!!!
============================== 1 failed in 0.43s ==============================


I have a very simple project for testing this:

.vscode\settings.json

{
"python.testing.pytestArgs": [
"--pdb"
],
"python.testing.unittestEnabled": false,
"python.testing.nosetestsEnabled": false,
"python.testing.pytestEnabled": true,
"git.ignoreLimitWarning": false
}


.vscode\launch.json

{
// Use IntelliSense to learn about possible attributes.
// Hover to view descriptions of existing attributes.
// For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
"version": "0.2.0",
"configurations": [


{
"name": "Python: Current File",
"type": "python",
"request": "launch",
"program": "${file}",
"console": "internalConsole",
"justMyCode":false
},
{
"name": "Python: Attach using Process Id",
"type": "python",
"request": "attach",
"processId": "${commandickProcess}",
"justMyCode": false
},
{
"name": "Debug Tests",
"type": "python",
"request": "test",
"console": "internalConsole",
"justMyCode": false
}
]
}


pytest.ini

[pytest]

python_files = test*.py
python_classes = Test
python_functions = test
addopts = --tb=native
console_output_style = classic
junit_duration_report = call
filterwarnings =
ignore::RuntimeWarning


and test.py:

def test_with_assert():
assert 42==2.71828


Is --pdb the correct way to do this? Or how do I enter the debugger upon an assert or error?

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