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pytest-forked: run each test in a forked subprocess


this is a extraction of the xdist --forked module, future maintenance beyond the bare minimum is not planned until a new maintainer is found.

This plugin does not work on Windows because there's no fork support.

  • --forked: run each test in a forked subprocess to survive SEGFAULTS or otherwise dying processes.

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Install the plugin with:

pip install pytest-forked

or use the package in develope/in-place mode with a checkout of the pytest-forked repository

pip install -e .

Usage examples

If you have tests involving C or C++ libraries you might have to deal with tests crashing the process. For this case you may use the boxing options:

pytest --forked

which will run each test in a subprocess and will report if a test crashed the process. You can also combine this option with running multiple processes via pytest-xdist to speed up the test run and use your CPU cores:

pytest -n3 --forked

this would run 3 testing subprocesses in parallel which each create new forked subprocesses for each test.

You can also fork for individual tests:

def test_with_leaky_state():

This test will be unconditionally boxed, regardless of CLI flag.