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.

Deprecated Features

Below is a complete list of all pytest features which are considered deprecated. Using those features will issue PytestWarning or subclasses, which can be filtered using standard warning filters.

The pytest.Instance collector

Removed in version 7.0.

The pytest.Instance collector type has been removed.

Previously, Python test methods were collected as Class -> Instance -> Function. Now Class collects the test methods directly.

Most plugins which reference Instance do so in order to ignore or skip it, using a check such as if isinstance(node, Instance): return. Such plugins should simply remove consideration of Instance on pytest>=7. However, to keep such uses working, a dummy type has been instanted in pytest.Instance and _pytest.python.Instance, and importing it emits a deprecation warning. This will be removed in pytest 8.

fspath argument for Node constructors replaced with pathlib.Path

Deprecated since version 7.0.

In order to support the transition from py.path.local to pathlib, the fspath argument to Node constructors like pytest.Function.from_parent() and pytest.Class.from_parent() is now deprecated.

Plugins which construct nodes should pass the path argument, of type pathlib.Path, instead of the fspath argument.

Plugins which implement custom items and collectors are encouraged to replace py.path.local fspath parameters with pathlib.Path parameters, and drop any other usage of the py library if possible.

py.path.local arguments for hooks replaced with pathlib.Path

Deprecated since version 7.0.

In order to support the transition from py.path.local to pathlib, the following hooks now receive additional arguments:

The accompanying py.path.local based paths have been deprecated: plugins which manually invoke those hooks should only pass the new pathlib.Path arguments, and users should change their hook implementations to use the new pathlib.Path arguments.

Directly constructing internal classes

Deprecated since version 7.0.

Directly constructing the following classes is now deprecated:

  • _pytest.mark.structures.Mark

  • _pytest.mark.structures.MarkDecorator

  • _pytest.mark.structures.MarkGenerator

  • _pytest.python.Metafunc

  • _pytest.runner.CallInfo

  • _pytest._code.ExceptionInfo

  • _pytest.config.argparsing.Parser

  • _pytest.config.argparsing.OptionGroup

  • _pytest.pytester.HookRecorder

These constructors have always been considered private, but now issue a deprecation warning, which may become a hard error in pytest 8.

Passing msg= to pytest.skip, pytest.fail or pytest.exit

Deprecated since version 7.0.

Passing the keyword argument msg to pytest.skip(), pytest.fail() or pytest.exit() is now deprecated and reason should be used instead. This change is to bring consistency between these functions and the``@pytest.mark.skip`` and @pytest.mark.xfail markers which already accept a reason argument.

def test_fail_example():
    # old
    pytest.fail(msg="foo")
    # new
    pytest.fail(reason="bar")


def test_skip_example():
    # old
    pytest.skip(msg="foo")
    # new
    pytest.skip(reason="bar")


def test_exit_example():
    # old
    pytest.exit(msg="foo")
    # new
    pytest.exit(reason="bar")

Implementing the pytest_cmdline_preparse hook

Deprecated since version 7.0.

Implementing the pytest_cmdline_preparse hook has been officially deprecated. Implement the pytest_load_initial_conftests hook instead.

def pytest_cmdline_preparse(config: Config, args: List[str]) -> None:
    ...


# becomes:


def pytest_load_initial_conftests(
    early_config: Config, parser: Parser, args: List[str]
) -> None:
    ...

Diamond inheritance between pytest.Collector and pytest.Item

Deprecated since version 7.0.

Defining a custom pytest node type which is both an pytest.Item and a pytest.Collector (e.g. pytest.File) now issues a warning. It was never sanely supported and triggers hard to debug errors.

Some plugins providing linting/code analysis have been using this as a hack. Instead, a separate collector node should be used, which collects the item. See Working with non-python tests for an example, as well as an example pr fixing inheritance.

Backward compatibilities in Parser.addoption

Deprecated since version 2.4.

Several behaviors of Parser.addoption are now scheduled for removal in pytest 8 (deprecated since pytest 2.4.0):

  • parser.addoption(..., help=".. %default ..") - use %(default)s instead.

  • parser.addoption(..., type="int/string/float/complex") - use type=int etc. instead.

Raising unittest.SkipTest during collection

Deprecated since version 7.0.

Raising unittest.SkipTest to skip collection of tests during the pytest collection phase is deprecated. Use pytest.skip() instead.

Note: This deprecation only relates to using unittest.SkipTest during test collection. You are probably not doing that. Ordinary usage of unittest.SkipTest / unittest.TestCase.skipTest() / unittest.skip() in unittest test cases is fully supported.

Using pytest.warns(None)

Deprecated since version 7.0.

pytest.warns(None) is now deprecated because many people used it to mean “this code does not emit warnings”, but it actually had the effect of checking that the code emits at least one warning of any type - like pytest.warns() or pytest.warns(Warning).

The --strict command-line option

Deprecated since version 6.2.

The --strict command-line option has been deprecated in favor of --strict-markers, which better conveys what the option does.

We have plans to maybe in the future to reintroduce --strict and make it an encompassing flag for all strictness related options (--strict-markers and --strict-config at the moment, more might be introduced in the future).

The yield_fixture function/decorator

Deprecated since version 6.2.

pytest.yield_fixture is a deprecated alias for pytest.fixture().

It has been so for a very long time, so can be search/replaced safely.

The pytest_warning_captured hook

Deprecated since version 6.0.

This hook has an item parameter which cannot be serialized by pytest-xdist.

Use the pytest_warning_recored hook instead, which replaces the item parameter by a nodeid parameter.

The pytest.collect module

Deprecated since version 6.0.

The pytest.collect module is no longer part of the public API, all its names should now be imported from pytest directly instead.

The pytest._fillfuncargs function

Deprecated since version 6.0.

This function was kept for backward compatibility with an older plugin.

It’s functionality is not meant to be used directly, but if you must replace it, use function._request._fillfixtures() instead, though note this is not a public API and may break in the future.

Removed Features

As stated in our Backwards Compatibility Policy policy, deprecated features are removed only in major releases after an appropriate period of deprecation has passed.

--no-print-logs command-line option

Deprecated since version 5.4.

Removed in version 6.0.

The --no-print-logs option and log_print ini setting are removed. If you used them, please use --show-capture instead.

A --show-capture command-line option was added in pytest 3.5.0 which allows to specify how to display captured output when tests fail: no, stdout, stderr, log or all (the default).

Result log (--result-log)

Deprecated since version 4.0.

Removed in version 6.0.

The --result-log option produces a stream of test reports which can be analysed at runtime, but it uses a custom format which requires users to implement their own parser.

The pytest-reportlog plugin provides a --report-log option, a more standard and extensible alternative, producing one JSON object per-line, and should cover the same use cases. Please try it out and provide feedback.

The pytest-reportlog plugin might even be merged into the core at some point, depending on the plans for the plugins and number of users using it.

pytest_collect_directory hook

Removed in version 6.0.

The pytest_collect_directory has not worked properly for years (it was called but the results were ignored). Users may consider using pytest_collection_modifyitems instead.

TerminalReporter.writer

Removed in version 6.0.

The TerminalReporter.writer attribute has been deprecated and should no longer be used. This was inadvertently exposed as part of the public API of that plugin and ties it too much with py.io.TerminalWriter.

Plugins that used TerminalReporter.writer directly should instead use TerminalReporter methods that provide the same functionality.

junit_family default value change to “xunit2”

Changed in version 6.0.

The default value of junit_family option will change to xunit2 in pytest 6.0, which is an update of the old xunit1 format and is supported by default in modern tools that manipulate this type of file (for example, Jenkins, Azure Pipelines, etc.).

Users are recommended to try the new xunit2 format and see if their tooling that consumes the JUnit XML file supports it.

To use the new format, update your pytest.ini:

[pytest]
junit_family=xunit2

If you discover that your tooling does not support the new format, and want to keep using the legacy version, set the option to legacy instead:

[pytest]
junit_family=legacy

By using legacy you will keep using the legacy/xunit1 format when upgrading to pytest 6.0, where the default format will be xunit2.

In order to let users know about the transition, pytest will issue a warning in case the --junitxml option is given in the command line but junit_family is not explicitly configured in pytest.ini.

Services known to support the xunit2 format:

Node Construction changed to Node.from_parent

Changed in version 6.0.

The construction of nodes now should use the named constructor from_parent. This limitation in api surface intends to enable better/simpler refactoring of the collection tree.

This means that instead of MyItem(name="foo", parent=collector, obj=42) one now has to invoke MyItem.from_parent(collector, name="foo").

Plugins that wish to support older versions of pytest and suppress the warning can use hasattr to check if from_parent exists in that version:

def pytest_pycollect_makeitem(collector, name, obj):
    if hasattr(MyItem, "from_parent"):
        item = MyItem.from_parent(collector, name="foo")
        item.obj = 42
        return item
    else:
        return MyItem(name="foo", parent=collector, obj=42)

Note that from_parent should only be called with keyword arguments for the parameters.

pytest.fixture arguments are keyword only

Removed in version 6.0.

Passing arguments to pytest.fixture() as positional arguments has been removed - pass them by keyword instead.

funcargnames alias for fixturenames

Removed in version 6.0.

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.

pytest.config global

Removed in version 5.0.

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.

"message" parameter of pytest.raises

Removed in version 5.0.

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:

with pytest.raises(TimeoutError, message="Client got unexpected message"):
    wait_for(websocket.recv(), 0.5)

Becomes:

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.

raises / warns with a string as the second argument

Removed in version 5.0.

Use the context manager form of these instead. When necessary, invoke exec directly.

Example:

pytest.raises(ZeroDivisionError, "1 / 0")
pytest.raises(SyntaxError, "a $ b")

pytest.warns(DeprecationWarning, "my_function()")
pytest.warns(SyntaxWarning, "assert(1, 2)")

Becomes:

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

Using Class in custom Collectors

Removed in version 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

Removed in version 4.0.

Applying marks to values of a pytest.mark.parametrize call is now deprecated. For example:

@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:

@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

Removed in version 4.0.

In very early pytest versions fixtures could be defined using the pytest_funcarg__ prefix:

def pytest_funcarg__data():
    return SomeData()

Switch over to the @pytest.fixture decorator:

@pytest.fixture
def data():
    return SomeData()

[pytest] section in setup.cfg files

Removed in version 4.0.

[pytest] sections in setup.cfg files should now be named [tool:pytest] to avoid conflicts with other distutils commands.

Metafunc.addcall

Removed in version 4.0.

Metafunc.addcall was a precursor to the current parametrized mechanism. Users should use pytest.Metafunc.parametrize() instead.

Example:

def pytest_generate_tests(metafunc):
    metafunc.addcall({"i": 1}, id="1")
    metafunc.addcall({"i": 2}, id="2")

Becomes:

def pytest_generate_tests(metafunc):
    metafunc.parametrize("i", [1, 2], ids=["1", "2"])

cached_setup

Removed in version 4.0.

request.cached_setup was the precursor of the setup/teardown mechanism available to fixtures.

Example:

@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:

@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

Removed in version 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

Removed in version 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:

config.warn("C1", "some warning")

Becomes:

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

Removed in version 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:

def test_foo(record_xml_property):
    ...

Change to:

def test_foo(record_property):
    ...

Passing command-line string to pytest.main()

Removed in version 4.0.

Passing a command-line string to pytest.main() is deprecated:

pytest.main("-v -s")

Pass a list instead:

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

Removed in version 4.0.

Calling a fixture function directly, as opposed to request them in a test function, is deprecated.

For example:

@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:

@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:

def cell():
    return ...


@pytest.fixture(name="cell")
def cell_fixture():
    return cell()

yield tests

Removed in version 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:

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:

@pytest.mark.parametrize("x, y", [(2, 4), (3, 9)])
def test_squared(x, y):
    assert x ** x == y

Internal classes accessed through Node

Removed in version 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

Removed in version 4.0.

As part of a large Marker revamp and iteration, _pytest.nodes.Node.get_marker is removed. See the documentation on tips on how to update your code.

somefunction.markname

Removed in version 4.0.

As part of a large Marker revamp and iteration we already deprecated using MarkInfo the only correct way to get markers of an element is via node.iter_markers(name).

pytest_namespace

Removed in version 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:

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:

import pytest


def pytest_configure():
    pytest.my_symbol = MySymbol()