.. _deprecations: Deprecations and Removals ========================= This page lists all pytest features that are currently deprecated or have been removed in past major releases. The objective is to give users a clear rationale why a certain feature has been removed, and what alternatives should be used instead. .. contents:: :depth: 3 :local: Deprecated Features ------------------- Below is a complete list of all pytest features which are considered deprecated. Using those features will issue :class:`_pytest.warning_types.PytestWarning` or subclasses, which can be filtered using :ref:`standard warning filters `. Removal of ``funcargnames`` alias for ``fixturenames`` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. deprecated:: 5.0 The ``FixtureRequest``, ``Metafunc``, and ``Function`` classes track the names of their associated fixtures, with the aptly-named ``fixturenames`` attribute. Prior to pytest 2.3, this attribute was named ``funcargnames``, and we have kept that as an alias since. It is finally due for removal, as it is often confusing in places where we or plugin authors must distinguish between fixture names and names supplied by non-fixture things such as ``pytest.mark.parametrize``. .. _`raises message deprecated`: ``"message"`` parameter of ``pytest.raises`` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. deprecated:: 4.1 It is a common mistake to think this parameter will match the exception message, while in fact it only serves to provide a custom message in case the ``pytest.raises`` check fails. To prevent users from making this mistake, and because it is believed to be little used, pytest is deprecating it without providing an alternative for the moment. If you have a valid use case for this parameter, consider that to obtain the same results you can just call ``pytest.fail`` manually at the end of the ``with`` statement. For example: .. code-block:: python with pytest.raises(TimeoutError, message="Client got unexpected message"): wait_for(websocket.recv(), 0.5) Becomes: .. code-block:: python with pytest.raises(TimeoutError): wait_for(websocket.recv(), 0.5) pytest.fail("Client got unexpected message") If you still have concerns about this deprecation and future removal, please comment on `issue #3974 `__. ``pytest.config`` global ~~~~~~~~~~~~~~~~~~~~~~~~ .. deprecated:: 4.1 The ``pytest.config`` global object is deprecated. Instead use ``request.config`` (via the ``request`` fixture) or if you are a plugin author use the ``pytest_configure(config)`` hook. Note that many hooks can also access the ``config`` object indirectly, through ``session.config`` or ``item.config`` for example. .. _raises-warns-exec: ``raises`` / ``warns`` with a string as the second argument ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. deprecated:: 4.1 Use the context manager form of these instead. When necessary, invoke ``exec`` directly. Example: .. code-block:: python pytest.raises(ZeroDivisionError, "1 / 0") pytest.raises(SyntaxError, "a $ b") pytest.warns(DeprecationWarning, "my_function()") pytest.warns(SyntaxWarning, "assert(1, 2)") Becomes: .. code-block:: python with pytest.raises(ZeroDivisionError): 1 / 0 with pytest.raises(SyntaxError): exec("a $ b") # exec is required for invalid syntax with pytest.warns(DeprecationWarning): my_function() with pytest.warns(SyntaxWarning): exec("assert(1, 2)") # exec is used to avoid a top-level warning Result log (``--result-log``) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. deprecated:: 4.0 The ``--result-log`` option produces a stream of test reports which can be analysed at runtime. It uses a custom format which requires users to implement their own parser, but the team believes using a line-based format that can be parsed using standard tools would provide a suitable and better alternative. The current plan is to provide an alternative in the pytest 5.0 series and remove the ``--result-log`` option in pytest 6.0 after the new implementation proves satisfactory to all users and is deemed stable. The actual alternative is still being discussed in issue `#4488 `__. Removed Features ---------------- As stated in our :ref:`backwards-compatibility` policy, deprecated features are removed only in major releases after an appropriate period of deprecation has passed. Using ``Class`` in custom Collectors ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 Using objects named ``"Class"`` as a way to customize the type of nodes that are collected in ``Collector`` subclasses has been deprecated. Users instead should use ``pytest_pycollect_makeitem`` to customize node types during collection. This issue should affect only advanced plugins who create new collection types, so if you see this warning message please contact the authors so they can change the code. marks in ``pytest.mark.parametrize`` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 Applying marks to values of a ``pytest.mark.parametrize`` call is now deprecated. For example: .. code-block:: python @pytest.mark.parametrize( "a, b", [ (3, 9), pytest.mark.xfail(reason="flaky")(6, 36), (10, 100), (20, 200), (40, 400), (50, 500), ], ) def test_foo(a, b): ... This code applies the ``pytest.mark.xfail(reason="flaky")`` mark to the ``(6, 36)`` value of the above parametrization call. This was considered hard to read and understand, and also its implementation presented problems to the code preventing further internal improvements in the marks architecture. To update the code, use ``pytest.param``: .. code-block:: python @pytest.mark.parametrize( "a, b", [ (3, 9), pytest.param(6, 36, marks=pytest.mark.xfail(reason="flaky")), (10, 100), (20, 200), (40, 400), (50, 500), ], ) def test_foo(a, b): ... ``pytest_funcarg__`` prefix ~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 In very early pytest versions fixtures could be defined using the ``pytest_funcarg__`` prefix: .. code-block:: python def pytest_funcarg__data(): return SomeData() Switch over to the ``@pytest.fixture`` decorator: .. code-block:: python @pytest.fixture def data(): return SomeData() [pytest] section in setup.cfg files ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 ``[pytest]`` sections in ``setup.cfg`` files should now be named ``[tool:pytest]`` to avoid conflicts with other distutils commands. Metafunc.addcall ~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 :meth:`_pytest.python.Metafunc.addcall` was a precursor to the current parametrized mechanism. Users should use :meth:`_pytest.python.Metafunc.parametrize` instead. Example: .. code-block:: python def pytest_generate_tests(metafunc): metafunc.addcall({"i": 1}, id="1") metafunc.addcall({"i": 2}, id="2") Becomes: .. code-block:: python def pytest_generate_tests(metafunc): metafunc.parametrize("i", [1, 2], ids=["1", "2"]) ``cached_setup`` ~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 ``request.cached_setup`` was the precursor of the setup/teardown mechanism available to fixtures. Example: .. code-block:: python @pytest.fixture def db_session(): return request.cached_setup( setup=Session.create, teardown=lambda session: session.close(), scope="module" ) This should be updated to make use of standard fixture mechanisms: .. code-block:: python @pytest.fixture(scope="module") def db_session(): session = Session.create() yield session session.close() You can consult `funcarg comparison section in the docs `_ for more information. pytest_plugins in non-top-level conftest files ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 Defining ``pytest_plugins`` is now deprecated in non-top-level conftest.py files because they will activate referenced plugins *globally*, which is surprising because for all other pytest features ``conftest.py`` files are only *active* for tests at or below it. ``Config.warn`` and ``Node.warn`` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 Those methods were part of the internal pytest warnings system, but since ``3.8`` pytest is using the builtin warning system for its own warnings, so those two functions are now deprecated. ``Config.warn`` should be replaced by calls to the standard ``warnings.warn``, example: .. code-block:: python config.warn("C1", "some warning") Becomes: .. code-block:: python warnings.warn(pytest.PytestWarning("some warning")) ``Node.warn`` now supports two signatures: * ``node.warn(PytestWarning("some message"))``: is now the **recommended** way to call this function. The warning instance must be a PytestWarning or subclass. * ``node.warn("CI", "some message")``: this code/message form has been **removed** and should be converted to the warning instance form above. record_xml_property ~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 The ``record_xml_property`` fixture is now deprecated in favor of the more generic ``record_property``, which can be used by other consumers (for example ``pytest-html``) to obtain custom information about the test run. This is just a matter of renaming the fixture as the API is the same: .. code-block:: python def test_foo(record_xml_property): ... Change to: .. code-block:: python def test_foo(record_property): ... Passing command-line string to ``pytest.main()`` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 Passing a command-line string to ``pytest.main()`` is deprecated: .. code-block:: python pytest.main("-v -s") Pass a list instead: .. code-block:: python pytest.main(["-v", "-s"]) By passing a string, users expect that pytest will interpret that command-line using the shell rules they are working on (for example ``bash`` or ``Powershell``), but this is very hard/impossible to do in a portable way. Calling fixtures directly ~~~~~~~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 Calling a fixture function directly, as opposed to request them in a test function, is deprecated. For example: .. code-block:: python @pytest.fixture def cell(): return ... @pytest.fixture def full_cell(): cell = cell() cell.make_full() return cell This is a great source of confusion to new users, which will often call the fixture functions and request them from test functions interchangeably, which breaks the fixture resolution model. In those cases just request the function directly in the dependent fixture: .. code-block:: python @pytest.fixture def cell(): return ... @pytest.fixture def full_cell(cell): cell.make_full() return cell Alternatively if the fixture function is called multiple times inside a test (making it hard to apply the above pattern) or if you would like to make minimal changes to the code, you can create a fixture which calls the original function together with the ``name`` parameter: .. code-block:: python def cell(): return ... @pytest.fixture(name="cell") def cell_fixture(): return cell() ``yield`` tests ~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 pytest supported ``yield``-style tests, where a test function actually ``yield`` functions and values that are then turned into proper test methods. Example: .. code-block:: python def check(x, y): assert x ** x == y def test_squared(): yield check, 2, 4 yield check, 3, 9 This would result into two actual test functions being generated. This form of test function doesn't support fixtures properly, and users should switch to ``pytest.mark.parametrize``: .. code-block:: python @pytest.mark.parametrize("x, y", [(2, 4), (3, 9)]) def test_squared(x, y): assert x ** x == y Internal classes accessed through ``Node`` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 Access of ``Module``, ``Function``, ``Class``, ``Instance``, ``File`` and ``Item`` through ``Node`` instances now issue this warning:: usage of Function.Module is deprecated, please use pytest.Module instead Users should just ``import pytest`` and access those objects using the ``pytest`` module. This has been documented as deprecated for years, but only now we are actually emitting deprecation warnings. ``Node.get_marker`` ~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 As part of a large :ref:`marker-revamp`, :meth:`_pytest.nodes.Node.get_marker` is deprecated. See :ref:`the documentation ` on tips on how to update your code. ``somefunction.markname`` ~~~~~~~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 As part of a large :ref:`marker-revamp` we already deprecated using ``MarkInfo`` the only correct way to get markers of an element is via ``node.iter_markers(name)``. ``pytest_namespace`` ~~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 4.0 This hook is deprecated because it greatly complicates the pytest internals regarding configuration and initialization, making some bug fixes and refactorings impossible. Example of usage: .. code-block:: python class MySymbol: ... def pytest_namespace(): return {"my_symbol": MySymbol()} Plugin authors relying on this hook should instead require that users now import the plugin modules directly (with an appropriate public API). As a stopgap measure, plugin authors may still inject their names into pytest's namespace, usually during ``pytest_configure``: .. code-block:: python import pytest def pytest_configure(): pytest.my_symbol = MySymbol() Reinterpretation mode (``--assert=reinterp``) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 3.0 Reinterpretation mode has now been removed and only plain and rewrite mode are available, consequently the ``--assert=reinterp`` option is no longer available. This also means files imported from plugins or ``conftest.py`` will not benefit from improved assertions by default, you should use ``pytest.register_assert_rewrite()`` to explicitly turn on assertion rewriting for those files. Removed command-line options ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 3.0 The following deprecated commandline options were removed: * ``--genscript``: no longer supported; * ``--no-assert``: use ``--assert=plain`` instead; * ``--nomagic``: use ``--assert=plain`` instead; * ``--report``: use ``-r`` instead; py.test-X* entry points ~~~~~~~~~~~~~~~~~~~~~~~ .. versionremoved:: 3.0 Removed all ``py.test-X*`` entry points. The versioned, suffixed entry points were never documented and a leftover from a pre-virtualenv era. These entry points also created broken entry points in wheels, so removing them also removes a source of confusion for users.