testland/pytest-asyncio-patterns
Configures and runs async Python tests with pytest-asyncio: installs the plugin, selects asyncio_mode (auto vs strict), scopes event loops (function/class/module/session), writes async fixtures with @pytest_asyncio.fixture, mocks coroutines with AsyncMock, and tests FastAPI (httpx.AsyncClient + ASGITransport) and aiohttp (aiohttp_client fixture) applications. Use when a Python project contains async def test_ functions, FastAPI/aiohttp endpoints, or any asyncio-based code that needs pytest integration. Do NOT use for general pytest fixture design, parametrize patterns, or conftest.py structure without an asyncio-specific problem (event-loop scoping, mode config, AsyncMock, ASGI client): use python-unit-tests for those.
93
93%
Does it follow best practices?
Impact
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Average score across 10 eval scenarios
Passed
No findings from the security scan
Evaluation results
Cannot share a connected client between these tests
CI has been green for tests it never ran
Flag endpoints explode under test, work in production
Green test, and the events still never left the box
Our aiohttp tests fight over port 8080
Seeded inventory is invisible to the request under test
Shared pool blows up once we stop rebuilding it per test
Shared setup fixture hands the test an async_generator
Stand-in for the HTTP client cannot be awaited
We ship this library to both async runtimes and only test one
- Agent
- Claude Code
- Model
- Claude Sonnet 4.6