Test: Accelerate pytests with some parallelisation

[mawildoer]

Speed-up ~2x in total time

New

====================================================================================================== test session starts ======================================================================================================
platform darwin -- Python 3.12.3, pytest-8.3.3, pluggy-1.5.0
rootdir: /Users/mattwildoer/Projects/faebryk-wt1
configfile: pyproject.toml
plugins: xdist-3.6.1
8 workers [547 items]   
......................................................................................................................................................................................................................... [ 39%]
......................................................................................................................................................................................................................... [ 79%]
....................................................................ss..........sssssssss...s....s...............                                                                                                         [100%]
======================================================================================================= warnings summary ========================================================================================================
test/libs/test_lcsc.py: 275 warnings
  /Users/mattwildoer/Projects/faebryk-wt1/.venv/lib/python3.12/site-packages/pydantic/_internal/_model_construction.py:293: PydanticDeprecatedSince20: The `__fields__` attribute is deprecated, use `model_fields` instead. Depr
ecated in Pydantic V2.0 to be removed in V3.0. See Pydantic V2 Migration Guide at https://errors.pydantic.dev/2.9/migration/                                                                                                         warnings.warn(

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
======================================================================================== 534 passed, 13 skipped, 275 warnings in 44.03s =========================================================================================
pytest -n auto  96.68s user 12.70s system 246% cpu 44.310 total

Old

====================================================================================================== test session starts ======================================================================================================
platform darwin -- Python 3.12.3, pytest-8.3.3, pluggy-1.5.0
rootdir: /Users/mattwildoer/Projects/faebryk-wt1
configfile: pyproject.toml
collected 547 items                                                                                                                                                                                                             

test/core/test_core.py .....                                                                                                                                                                                              [  0%]
test/core/test_hierarchy_connect.py .....                                                                                                                                                                                 [  1%]
test/core/test_parameters.py ........                                                                                                                                                                                     [  3%]
test/core/test_performance.py ...                                                                                                                                                                                         [  3%]
test/core/test_traits.py .......                                                                                                                                                                                          [  5%]
test/core/test_util.py .                                                                                                                                                                                                  [  5%]
test/exporters/netlist/kicad/test_netlist_kicad.py .                                                                                                                                                                      [  5%]
test/exporters/pcb/kicad/test_transformer.py .                                                                                                                                                                            [  5%]
test/importers/netlist/kicad/test_schematic_kicad.py s                                                                                                                                                                    [  5%]
test/integration/netlist/kicad2faebryk/test_netlist_kicad_2_faebryk_prj.py s                                                                                                                                              [  6%]
test/library/nodes/test_electricpower.py .                                                                                                                                                                                [  6%]
test/library/test_basic.py .............................................................................................................................................................................................. [ 40%]
......................................................................................................................................................................................................................... [ 80%]
....................................................................                                                                                                                                                      [ 93%]
test/library/test_footprints.py ..                                                                                                                                                                                        [ 93%]
test/library/test_names.py .                                                                                                                                                                                              [ 93%]
test/library/test_reference.py ......                                                                                                                                                                                     [ 94%]
test/libs/kicad/test_fileformats.py ..........                                                                                                                                                                            [ 96%]
test/libs/picker/test_jlcpcb.py ssssssssss                                                                                                                                                                                [ 98%]
test/libs/test_e_series.py ...                                                                                                                                                                                            [ 98%]
test/libs/test_lcsc.py .                                                                                                                                                                                                  [ 99%]
test/libs/test_util.py ....                                                                                                                                                                                               [ 99%]
test/libs/test_util_atexit.py s                                                                                                                                                                                           [100%]

======================================================================================================= warnings summary ========================================================================================================
test/libs/test_lcsc.py: 275 warnings
  /Users/mattwildoer/Projects/faebryk-wt1/.venv/lib/python3.12/site-packages/pydantic/_internal/_model_construction.py:293: PydanticDeprecatedSince20: The `__fields__` attribute is deprecated, use `model_fields` instead. Depre
cated in Pydantic V2.0 to be removed in V3.0. See Pydantic V2 Migration Guide at https://errors.pydantic.dev/2.9/migration/                                                                                                           warnings.warn(

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
=================================================================================== 534 passed, 13 skipped, 275 warnings in 86.34s (0:01:26) ====================================================================================
pytest  75.35s user 9.12s system 95% cpu 1:28.70 total

[mawildoer]

Seems like we only see a very very mild improvement on the CI runners, because they're done on machines with only 2 CPUs, but it's still an improvement and locally it's vastly better!

[iopapamanoglou]

Very cool!
I made it also run locally in parallel.
Seems to work: