Incompatibility between Pytest 5 and eventlet

README.md

Setup

pip install pytest==5.0.1 eventlet

See error

pytest --help | cat

No error without faulthandler

pytest --no-faulthandler --help | cat

No error before pytest 5

pip install 'pytest<=5'
pytest --help | cat

Git bisect located this commit as the cause:

• Commit: https://github.com/pytest-dev/pytest/commit/a37b902afea216216
• Issue: pytest-dev/pytest#5440

conftest.py

def pytest_configure():
    # make sure we monkey_patch before `--help` is run
    import eventlet
    eventlet.monkey_patch()