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.

Support for tests written for nose ¶

自 7.2 版本弃用.

Support for running tests written for nose is now deprecated.

nose has been in maintenance mode-only for years, and maintaining the plugin is not trivial as it spills over the code base (see issue #9886 for more details).

setup/teardown ¶

One thing that might catch users by surprise is that plain setup and teardown methods are not pytest native, they are in fact part of the nose support.

class Test:
    def setup(self):
        self.resource = make_resource()

    def teardown(self):
        self.resource.close()

    def test_foo(self):
        ...

    def test_bar(self):
        ...

Native pytest support uses setup_method and teardown_method (see Method and function level setup/teardown), so the above should be changed to:

class Test:
    def setup_method(self):
        self.resource = make_resource()

    def teardown_method(self):
        self.resource.close()

    def test_foo(self):
        ...

    def test_bar(self):
        ...

This is easy to do in an entire code base by doing a simple find/replace.

@with_setup ¶

Code using @with_setup such as this:

from nose.tools import with_setup

def setup_some_resource():
    ...

def teardown_some_resource():
    ...

@with_setup(setup_some_resource, teardown_some_resource)
def test_foo():
    ...

Will also need to be ported to a supported pytest style. One way to do it is using a fixture:

import pytest


def setup_some_resource():
    ...


def teardown_some_resource():
    ...


@pytest.fixture
def some_resource():
    setup_some_resource()
    yield
    teardown_some_resource()


def test_foo(some_resource):
    ...

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`¶

自 7.0 版本弃用.

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 fspath parameters (py.path.local) with path parameters (pathlib.Path), and drop any other usage of the py library if possible.

If possible, plugins with custom items should use cooperative constructors to avoid hardcoding arguments they only pass on to the superclass.

备注

The name of the Node arguments and attributes (the new attribute being path) is the opposite of the situation for hooks, outlined below (the old argument being path).

This is an unfortunate artifact due to historical reasons, which should be resolved in future versions as we slowly get rid of the py dependency (see issue #9283 for a longer discussion).

Due to the ongoing migration of methods like reportinfo() which still is expected to return a py.path.local object, nodes still have both fspath (py.path.local) and path (pathlib.Path) attributes, no matter what argument was used in the constructor. We expect to deprecate the fspath attribute in a future release.

Configuring hook specs/impls using markers ¶

Before pluggy, pytest’s plugin library, was its own package and had a clear API, pytest just used pytest.mark to configure hooks.

The pytest.hookimpl() and pytest.hookspec() decorators have been available since years and should be used instead.

@pytest.mark.tryfirst
def pytest_runtest_call():
    ...


# or
def pytest_runtest_call():
    ...


pytest_runtest_call.tryfirst = True

should be changed to:

@pytest.hookimpl(tryfirst=True)
def pytest_runtest_call():
    ...

Changed hookimpl attributes:

tryfirst
trylast
optionalhook
hookwrapper

Changed hookwrapper attributes:

firstresult
historic

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

自 7.0 版本弃用.

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

pytest_ignore_collect(collection_path: pathlib.Path) as equivalent to path
pytest_collect_file(file_path: pathlib.Path) as equivalent to path
pytest_pycollect_makemodule(module_path: pathlib.Path) as equivalent to path
pytest_report_header(start_path: pathlib.Path) as equivalent to startdir
pytest_report_collectionfinish(start_path: pathlib.Path) as equivalent to startdir

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.

备注

The name of the Node arguments and attributes, outlined above (the new attribute being path) is the opposite of the situation for hooks (the old argument being path).

This is an unfortunate artifact due to historical reasons, which should be resolved in future versions as we slowly get rid of the py dependency (see issue #9283 for a longer discussion).

Directly constructing internal classes ¶

自 7.0 版本弃用.

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`¶

自 7.0 版本弃用.

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 ¶

自 7.0 版本弃用.

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`¶

自 7.0 版本弃用.

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.

Constructors of custom `pytest.Node` subclasses should take `**kwargs`¶

自 7.0 版本弃用.

If custom subclasses of nodes like pytest.Item override the __init__ method, they should take **kwargs. Thus,

class CustomItem(pytest.Item):
    def __init__(self, name, parent, additional_arg):
        super().__init__(name, parent)
        self.additional_arg = additional_arg

should be turned into:

class CustomItem(pytest.Item):
    def __init__(self, *, additional_arg, **kwargs):
        super().__init__(**kwargs)
        self.additional_arg = additional_arg

to avoid hard-coding the arguments pytest can pass to the superclass. See Working with non-python tests for a full example.

For cases without conflicts, no deprecation warning is emitted. For cases with conflicts (such as pytest.File now taking path instead of fspath, as outlined above), a deprecation warning is now raised.

Backward compatibilities in `Parser.addoption`¶

自 2.4 版本弃用.

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.

Using `pytest.warns(None)`¶

自 7.0 版本弃用.

pytest.warns(None) is now deprecated because it was frequently misused. Its correct usage was checking that the code emits at least one warning of any type - like pytest.warns() or pytest.warns(Warning).

See Additional use cases of warnings in tests for examples.

Returning non-None value in test functions ¶

自 7.2 版本弃用.

A pytest.PytestReturnNotNoneWarning is now emitted if a test function returns something other than None.

This prevents a common mistake among beginners that expect that returning a bool would cause a test to pass or fail, for example:

@pytest.mark.parametrize(
    ["a", "b", "result"],
    [
        [1, 2, 5],
        [2, 3, 8],
        [5, 3, 18],
    ],
)
def test_foo(a, b, result):
    return foo(a, b) == result

Given that pytest ignores the return value, this might be surprising that it will never fail.

The proper fix is to change the return to an assert:

@pytest.mark.parametrize(
    ["a", "b", "result"],
    [
        [1, 2, 5],
        [2, 3, 8],
        [5, 3, 18],
    ],
)
def test_foo(a, b, result):
    assert foo(a, b) == result

The `--strict` command-line option ¶

自 6.2 版本弃用.

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 ¶

自 6.2 版本弃用.

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.

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.

The `pytest.collect` module ¶

自 6.0 版本弃用.

Removed in version 7.0.

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_warning_captured` hook ¶

自 6.0 版本弃用.

Removed in version 7.0.

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

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

The `pytest._fillfuncargs` function ¶

自 6.0 版本弃用.

Removed in version 7.0.

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.

`--no-print-logs` command-line option ¶

自 5.4 版本弃用.

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`)¶

自 4.0 版本弃用.

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 hook 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”¶

在 6.0 版本发生变更.

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:

Jenkins with the JUnit plugin.
Azure Pipelines.

Node Construction changed to `Node.from_parent`¶

在 6.0 版本发生变更.

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()

Deprecations and Removals¶

Diamond inheritance between pytest.Collector and pytest.Item¶

Diamond inheritance between `pytest.Collector` and `pytest.Item`¶