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.
pytest.importorskip
default behavior regarding ImportError
¶
Deprecated since version 8.2.
Traditionally pytest.importorskip()
will capture ImportError
, with the original intent being to skip
tests where a dependent module is not installed, for example testing with different dependencies.
However some packages might be installed in the system, but are not importable due to
some other issue, for example, a compilation error or a broken installation. In those cases pytest.importorskip()
would still silently skip the test, but more often than not users would like to see the unexpected
error so the underlying issue can be fixed.
In 8.2
the exc_type
parameter has been added, giving users the ability of passing ModuleNotFoundError
to skip tests only if the module cannot really be found, and not because of some other error.
Catching only ModuleNotFoundError
by default (and letting other errors propagate) would be the best solution,
however for backward compatibility, pytest will keep the existing behavior but raise an warning if:
The captured exception is of type
ImportError
, and:The user does not pass
exc_type
explicitly.
If the import attempt raises ModuleNotFoundError
(the usual case), then the module is skipped and no
warning is emitted.
This way, the usual cases will keep working the same way, while unexpected errors will now issue a warning, with
users being able to supress the warning by passing exc_type=ImportError
explicitly.
In 9.0
, the warning will turn into an error, and in 9.1
pytest.importorskip()
will only capture
ModuleNotFoundError
by default and no warnings will be issued anymore – but users can still capture
ImportError
by passing it to exc_type
.
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
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.
Note
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 #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
¶
Deprecated since version 7.0.
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 topath
pytest_collect_file(file_path: pathlib.Path)
as equivalent topath
pytest_pycollect_makemodule(module_path: pathlib.Path)
as equivalent topath
pytest_report_header(start_path: pathlib.Path)
as equivalent tostartdir
pytest_report_collectionfinish(start_path: pathlib.Path)
as equivalent tostartdir
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.
Note
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 #9283 for a longer discussion).
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.
Diamond inheritance between pytest.Collector
and pytest.Item
¶
Deprecated since version 7.0.
Defining a custom pytest node type which is both an Item
and a Collector
(e.g. 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 Node
subclasses should take **kwargs
¶
Deprecated since version 7.0.
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.
Applying a mark to a fixture function¶
Deprecated since version 7.4.
Applying a mark to a fixture function never had any effect, but it is a common user error.
@pytest.mark.usefixtures("clean_database")
@pytest.fixture
def user() -> User: ...
Users expected in this case that the usefixtures
mark would have its intended effect of using the clean_database
fixture when user
was invoked, when in fact it has no effect at all.
Now pytest will issue a warning when it encounters this problem, and will raise an error in the future versions.
Returning non-None value in test functions¶
Deprecated since version 7.2.
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 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.
Removed Features and Breaking Changes¶
As stated in our Backwards Compatibility Policy policy, deprecated features are removed only in major releases after an appropriate period of deprecation has passed.
Some breaking changes which could not be deprecated are also listed.
Support for tests written for nose¶
Deprecated since version 7.2.
Removed in version 8.0.
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 #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 compat_co_firstlineno
attribute¶
Nose inspects this attribute on function objects to allow overriding the function’s inferred line number. Pytest no longer respects this attribute.
Passing msg=
to pytest.skip
, pytest.fail
or pytest.exit
¶
Deprecated since version 7.0.
Removed in version 8.0.
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")
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 instanced in pytest.Instance
and _pytest.python.Instance
,
and importing it emits a deprecation warning. This was removed in pytest 8.
Using pytest.warns(None)
¶
Deprecated since version 7.0.
Removed in version 8.0.
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.
Backward compatibilities in Parser.addoption
¶
Deprecated since version 2.4.
Removed in version 8.0.
Several behaviors of Parser.addoption
are now
removed in pytest 8 (deprecated since pytest 2.4.0):
parser.addoption(..., help=".. %default ..")
- use%(default)s
instead.parser.addoption(..., type="int/string/float/complex")
- usetype=int
etc. instead.
The --strict
command-line option¶
Deprecated since version 6.2.
Removed in version 8.0.
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).
Implementing the pytest_cmdline_preparse
hook¶
Deprecated since version 7.0.
Removed in version 8.0.
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: ...
Collection changes in pytest 8¶
Added a new pytest.Directory
base collection node, which all collector nodes for filesystem directories are expected to subclass.
This is analogous to the existing pytest.File
for file nodes.
Changed pytest.Package
to be a subclass of pytest.Directory
.
A Package
represents a filesystem directory which is a Python package,
i.e. contains an __init__.py
file.
pytest.Package
now only collects files in its own directory; previously it collected recursively.
Sub-directories are collected as sub-collector nodes, thus creating a collection tree which mirrors the filesystem hierarchy.
session.name
is now ""
; previously it was the rootdir directory name.
This matches session.nodeid
which has always been ""
.
Added a new pytest.Dir
concrete collection node, a subclass of pytest.Directory
.
This node represents a filesystem directory, which is not a pytest.Package
,
i.e. does not contain an __init__.py
file.
Similarly to Package
, it only collects the files in its own directory,
while collecting sub-directories as sub-collector nodes.
Files and directories are now collected in alphabetical order jointly, unless changed by a plugin. Previously, files were collected before directories.
The collection tree now contains directories/packages up to the rootdir, for initial arguments that are found within the rootdir. For files outside the rootdir, only the immediate directory/package is collected – note however that collecting from outside the rootdir is discouraged.
As an example, given the following filesystem tree:
myroot/
pytest.ini
top/
├── aaa
│ └── test_aaa.py
├── test_a.py
├── test_b
│ ├── __init__.py
│ └── test_b.py
├── test_c.py
└── zzz
├── __init__.py
└── test_zzz.py
the collection tree, as shown by pytest --collect-only top/
but with the otherwise-hidden Session
node added for clarity,
is now the following:
<Session>
<Dir myroot>
<Dir top>
<Dir aaa>
<Module test_aaa.py>
<Function test_it>
<Module test_a.py>
<Function test_it>
<Package test_b>
<Module test_b.py>
<Function test_it>
<Module test_c.py>
<Function test_it>
<Package zzz>
<Module test_zzz.py>
<Function test_it>
Previously, it was:
<Session>
<Module top/test_a.py>
<Function test_it>
<Module top/test_c.py>
<Function test_it>
<Module top/aaa/test_aaa.py>
<Function test_it>
<Package test_b>
<Module test_b.py>
<Function test_it>
<Package zzz>
<Module test_zzz.py>
<Function test_it>
Code/plugins which rely on a specific shape of the collection tree might need to update.
pytest.Package
is no longer a pytest.Module
or pytest.File
¶
Changed in version 8.0.
The Package
collector node designates a Python package, that is, a directory with an __init__.py
file.
Previously Package
was a subtype of pytest.Module
(which represents a single Python module),
the module being the __init__.py
file.
This has been deemed a design mistake (see #11137 and #7777 for details).
The path
property of Package
nodes now points to the package directory instead of the __init__.py
file.
Note that a Module
node for __init__.py
(which is not a Package
) may still exist,
if it is picked up during collection (e.g. if you configured python_files
to include __init__.py
files).
Collecting __init__.py
files no longer collects package¶
Removed in version 8.0.
Running pytest pkg/__init__.py
now collects the pkg/__init__.py
file (module) only.
Previously, it collected the entire pkg
package, including other test files in the directory, but excluding tests in the __init__.py
file itself
(unless python_files
was changed to allow __init__.py
file).
To collect the entire package, specify just the directory: pytest pkg
.
The pytest.collect
module¶
Deprecated since version 6.0.
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¶
Deprecated since version 6.0.
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¶
Deprecated since version 6.0.
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¶
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
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”¶
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 --junit-xml
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 #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()