Getting Started

Installation

pip install pytest-concurrency

Basic Usage

Enable Parallel Execution

# Run with 4 workers
pytest --workers 4

# Auto-detect CPU count
pytest --workers auto

Environment Variables

You can also configure workers via environment variable:

PYTEST_CONCURRENCY_WORKERS=4 pytest

How It Works

When --workers is provided or PYTEST_CONCURRENCY_WORKERS is set, the plugin:

1. Patches pytest internals — makes SetupState, FixtureDef, and os.environ thread-local
2. Collects all tests — standard pytest collection
3. Groups parametrized tests — keeps same test function with different params together
4. Distributes across workers — round-robin assignment for balanced load
5. Runs in parallel threads — each worker executes its test suite

Compatibility

• Python 3.10+
• pytest 7.0+
• Optional: allure-pytest for Allure integration

Limitations

• Tests must be thread-safe (no shared mutable state)
• Fixtures should not rely on process-level state
• Some pytest plugins may be incompatible with threading