Metadata-Version: 2.1 Name: pytest-asyncio Version: 0.19.0 Summary: Pytest support for asyncio Home-page: https://github.com/pytest-dev/pytest-asyncio Author: Tin Tvrtković Author-email: tinchester@gmail.com License: Apache 2.0 Project-URL: GitHub, https://github.com/pytest-dev/pytest-asyncio Classifier: Development Status :: 4 - Beta Classifier: Intended Audience :: Developers Classifier: License :: OSI Approved :: Apache Software License Classifier: Programming Language :: Python :: 3.7 Classifier: Programming Language :: Python :: 3.8 Classifier: Programming Language :: Python :: 3.9 Classifier: Programming Language :: Python :: 3.10 Classifier: Programming Language :: Python :: 3.11 Classifier: Topic :: Software Development :: Testing Classifier: Framework :: AsyncIO Classifier: Framework :: Pytest Classifier: Typing :: Typed Requires-Python: >=3.7 Description-Content-Type: text/x-rst Provides-Extra: testing License-File: LICENSE pytest-asyncio: pytest support for asyncio ========================================== .. image:: https://img.shields.io/pypi/v/pytest-asyncio.svg :target: https://pypi.python.org/pypi/pytest-asyncio .. image:: https://github.com/pytest-dev/pytest-asyncio/workflows/CI/badge.svg :target: https://github.com/pytest-dev/pytest-asyncio/actions?workflow=CI .. image:: https://codecov.io/gh/pytest-dev/pytest-asyncio/branch/master/graph/badge.svg :target: https://codecov.io/gh/pytest-dev/pytest-asyncio .. image:: https://img.shields.io/pypi/pyversions/pytest-asyncio.svg :target: https://github.com/pytest-dev/pytest-asyncio :alt: Supported Python versions .. image:: https://img.shields.io/badge/code%20style-black-000000.svg :target: https://github.com/ambv/black pytest-asyncio is an Apache2 licensed library, written in Python, for testing asyncio code with pytest. asyncio code is usually written in the form of coroutines, which makes it slightly more difficult to test using normal testing tools. pytest-asyncio provides useful fixtures and markers to make testing easier. .. code-block:: python @pytest.mark.asyncio async def test_some_asyncio_code(): res = await library.do_something() assert b"expected result" == res pytest-asyncio has been strongly influenced by pytest-tornado_. .. _pytest-tornado: https://github.com/eugeniy/pytest-tornado Features -------- - fixtures for creating and injecting versions of the asyncio event loop - fixtures for injecting unused tcp/udp ports - pytest markers for treating tests as asyncio coroutines - easy testing with non-default event loops - support for `async def` fixtures and async generator fixtures - support *auto* mode to handle all async fixtures and tests automatically by asyncio; provide *strict* mode if a test suite should work with different async frameworks simultaneously, e.g. ``asyncio`` and ``trio``. Installation ------------ To install pytest-asyncio, simply: .. code-block:: bash $ pip install pytest-asyncio This is enough for pytest to pick up pytest-asyncio. Modes ----- Starting from ``pytest-asyncio>=0.17``, three modes are provided: *auto*, *strict* and *legacy*. Starting from ``pytest-asyncio>=0.19`` the *strict* mode is the default. The mode can be set by ``asyncio_mode`` configuration option in `configuration file `_: .. code-block:: ini # pytest.ini [pytest] asyncio_mode = auto The value can be overridden by command-line option for ``pytest`` invocation: .. code-block:: bash $ pytest tests --asyncio-mode=strict Auto mode ~~~~~~~~~ When the mode is auto, all discovered *async* tests are considered *asyncio-driven* even if they have no ``@pytest.mark.asyncio`` marker. All async fixtures are considered *asyncio-driven* as well, even if they are decorated with a regular ``@pytest.fixture`` decorator instead of dedicated ``@pytest_asyncio.fixture`` counterpart. *asyncio-driven* means that tests and fixtures are executed by ``pytest-asyncio`` plugin. This mode requires the simplest tests and fixtures configuration and is recommended for default usage *unless* the same project and its test suite should execute tests from different async frameworks, e.g. ``asyncio`` and ``trio``. In this case, auto-handling can break tests designed for other framework; please use *strict* mode instead. Strict mode ~~~~~~~~~~~ Strict mode enforces ``@pytest.mark.asyncio`` and ``@pytest_asyncio.fixture`` usage. Without these markers, tests and fixtures are not considered as *asyncio-driven*, other pytest plugin can handle them. Please use this mode if multiple async frameworks should be combined in the same test suite. This mode is used by default for the sake of project inter-compatibility. Legacy mode ~~~~~~~~~~~ This mode follows rules used by ``pytest-asyncio<0.17``: tests are not auto-marked but fixtures are. Deprecation warnings are emitted with suggestion to either switching to ``auto`` mode or using ``strict`` mode with ``@pytest_asyncio.fixture`` decorators. The default was changed to ``strict`` in ``pytest-asyncio>=0.19``. Fixtures -------- ``event_loop`` ~~~~~~~~~~~~~~ Creates a new asyncio event loop based on the current event loop policy. The new loop is available as the return value of this fixture or via `asyncio.get_running_loop `__. The event loop is closed when the fixture scope ends. The fixture scope defaults to ``function`` scope. Note that just using the ``event_loop`` fixture won't make your test function a coroutine. You'll need to interact with the event loop directly, using methods like ``event_loop.run_until_complete``. See the ``pytest.mark.asyncio`` marker for treating test functions like coroutines. .. code-block:: python def test_http_client(event_loop): url = "http://httpbin.org/get" resp = event_loop.run_until_complete(http_client(url)) assert b"HTTP/1.1 200 OK" in resp The ``event_loop`` fixture can be overridden in any of the standard pytest locations, e.g. directly in the test file, or in ``conftest.py``. This allows redefining the fixture scope, for example: .. code-block:: python @pytest.fixture(scope="session") def event_loop(): policy = asyncio.get_event_loop_policy() loop = policy.new_event_loop() yield loop loop.close() If you need to change the type of the event loop, prefer setting a custom event loop policy over redefining the ``event_loop`` fixture. If the ``pytest.mark.asyncio`` marker is applied to a test function, the ``event_loop`` fixture will be requested automatically by the test function. ``unused_tcp_port`` ~~~~~~~~~~~~~~~~~~~ Finds and yields a single unused TCP port on the localhost interface. Useful for binding temporary test servers. ``unused_tcp_port_factory`` ~~~~~~~~~~~~~~~~~~~~~~~~~~~ A callable which returns a different unused TCP port each invocation. Useful when several unused TCP ports are required in a test. .. code-block:: python def a_test(unused_tcp_port_factory): port1, port2 = unused_tcp_port_factory(), unused_tcp_port_factory() ... ``unused_udp_port`` and ``unused_udp_port_factory`` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Work just like their TCP counterparts but return unused UDP ports. Async fixtures ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Asynchronous fixtures are defined just like ordinary pytest fixtures, except they should be decorated with ``@pytest_asyncio.fixture``. .. code-block:: python3 import pytest_asyncio @pytest_asyncio.fixture async def async_gen_fixture(): await asyncio.sleep(0.1) yield "a value" @pytest_asyncio.fixture(scope="module") async def async_fixture(): return await asyncio.sleep(0.1) All scopes are supported, but if you use a non-function scope you will need to redefine the ``event_loop`` fixture to have the same or broader scope. Async fixtures need the event loop, and so must have the same or narrower scope than the ``event_loop`` fixture. *auto* and *legacy* mode automatically converts async fixtures declared with the standard ``@pytest.fixture`` decorator to *asyncio-driven* versions. Markers ------- ``pytest.mark.asyncio`` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Mark your test coroutine with this marker and pytest will execute it as an asyncio task using the event loop provided by the ``event_loop`` fixture. See the introductory section for an example. The event loop used can be overridden by overriding the ``event_loop`` fixture (see above). In order to make your test code a little more concise, the pytest |pytestmark|_ feature can be used to mark entire modules or classes with this marker. Only test coroutines will be affected (by default, coroutines prefixed by ``test_``), so, for example, fixtures are safe to define. .. code-block:: python import asyncio import pytest # All test coroutines will be treated as marked. pytestmark = pytest.mark.asyncio async def test_example(event_loop): """No marker!""" await asyncio.sleep(0, loop=event_loop) In *auto* mode, the ``pytest.mark.asyncio`` marker can be omitted, the marker is added automatically to *async* test functions. .. |pytestmark| replace:: ``pytestmark`` .. _pytestmark: http://doc.pytest.org/en/latest/example/markers.html#marking-whole-classes-or-modules Note about unittest ------------------- Test classes subclassing the standard `unittest `__ library are not supported, users are recommended to use `unittest.IsolatedAsyncioTestCase `__ or an async framework such as `asynctest `__. Contributing ------------ Contributions are very welcome. Tests can be run with ``tox``, please ensure the coverage at least stays the same before you submit a pull request.