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
PytestWarning{.interpreted-text role=“class”} or subclasses, which can
be filtered using
standard warning filters <warnings>{.interpreted-text role=“ref”}.
The --strict command-line option
::: {.deprecated}
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}
6.2
:::
pytest.yield_fixture is a deprecated alias for
pytest.fixture{.interpreted-text role=“func”}.
It has been so for a very long time, so can be search/replaced safely.
The pytest_warning_captured hook
::: {.deprecated}
6.0
:::
This hook has an [item]{.title-ref} 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}
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}
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()]{.title-ref}
instead, though note this is not a public API and may break in the
future.
Removed Features
As stated in our backwards-compatibility{.interpreted-text role=“ref”}
policy, deprecated features are removed only in major releases after an
appropriate period of deprecation has passed.
--no-print-logs command-line option
::: {.deprecated}
5.4
:::
::: {.versionremoved}
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}
4.0
:::
::: {.versionremoved}
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
::: {.versionremoved}
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 <_pytest.hookspec.pytest_collection_modifyitems>{.interpreted-text
role=“func”} instead.
TerminalReporter.writer
::: {.versionremoved}
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"
::: {.versionchanged}
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:
-
Jenkins with the
JUnit plugin. -
Azure
Pipelines.
Node Construction changed to Node.from_parent
::: {.versionchanged}
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]{.title-ref} to check if
[from_parent]{.title-ref} 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
::: {.versionremoved}
6.0
:::
Passing arguments to pytest.fixture() as positional arguments has been
removed - pass them by keyword instead.
funcargnames alias for fixturenames
::: {.versionremoved}
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
::: {.versionremoved}
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 {#raises message deprecated}
::: {.versionremoved}
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 {#raises-warns-exec}
::: {.versionremoved}
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
::: {.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:
@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
::: {.versionremoved}
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
::: {.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
:::
_pytest.python.Metafunc.addcall was a precursor to the current
parametrized mechanism. Users should use
_pytest.python.Metafunc.parametrize{.interpreted-text role=“meth”}
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
::: {.versionremoved}
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
::: {.versionremoved}
4.0
:::
Defining pytest_plugins{.interpreted-text role=“globalvar”} 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:
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
::: {.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:
def test_foo(record_xml_property):
...
Change to:
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:
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
::: {.versionremoved}
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
::: {.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:
def check(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):
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 marker-revamp{.interpreted-text role=“ref”},
_pytest.nodes.Node.get_marker is removed. See
the documentation <update marker code>{.interpreted-text role=“ref”}
on tips on how to update your code.
somefunction.markname
::: {.versionremoved}
4.0
:::
As part of a large marker-revamp{.interpreted-text role=“ref”} 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:
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()