A coroutine or async generator with this marker is treated as a test function by pytest. The marked function is executed as an asyncio task in the event loop provided by pytest-asyncio.
Multiple async tests in a single class or module can be marked using pytestmark.
The pytest.mark.asyncio marker can be omitted entirely in auto mode where the asyncio marker is added automatically to async test functions.
By default, each test runs in it's own asyncio event loop. Multiple tests can share the same event loop by providing a scope keyword argument to the asyncio mark. The supported scopes are class, and module, and package. The following code example provides a shared event loop for all tests in TestClassScopedLoop:
Requesting class scope with the test being part of a class will give a UsageError. Similar to class-scoped event loops, a module-scoped loop is provided when setting mark's scope to module:
Package-scoped loops only work with regular Python packages. That means they require an __init__.py to be present. Package-scoped loops do not work in namespace packages. Subpackages do not share the loop with their parent package.
Tests marked with session scope share the same event loop, even if the tests exist in different packages.