test_ok1/doc/en/reference.rst

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Reference
=========
This page contains the full reference to pytest's API.
.. contents::
:depth: 3
:local:
pytest.approx
-------------
.. autofunction:: _pytest.python_api.approx
outcomes
--------
You can use the following functions in your test, fixture or setup
functions to force a certain test outcome. Note that most often
you can rather use declarative marks, see :ref:`skipping`.
pytest.fail
~~~~~~~~~~~
.. autofunction:: _pytest.outcomes.fail
pytest.skip
~~~~~~~~~~~
.. autofunction:: _pytest.outcomes.skip(msg, [allow_module_level=False])
pytest.importorskip
~~~~~~~~~~~~~~~~~~~
.. autofunction:: _pytest.outcomes.importorskip
pytest.xfail
~~~~~~~~~~~~
.. autofunction:: _pytest.outcomes.xfail
pytest.exit
-----------
.. autofunction:: _pytest.outcomes.exit
pytest.main
-----------
.. autofunction:: _pytest.config.main
pytest.param
------------
.. autofunction:: pytest.param(*values, [id], [marks])
pytest.raises
-------------
**Tutorial**: :ref:`assertraises`.
.. autofunction:: pytest.raises(expected_exception: Exception, [match], [message])
:with: excinfo
pytest.deprecated_call
----------------------
**Tutorial**: :ref:`ensuring_function_triggers`.
.. autofunction:: pytest.deprecated_call()
:with:
pytest.register_assert_rewrite
------------------------------
**Tutorial**: :ref:`assertion-rewriting`.
.. autofunction:: pytest.register_assert_rewrite
pytest.warns
------------
**Tutorial**: :ref:`assertwarnings`
.. autofunction:: pytest.warns(expected_warning: Exception, [match])
:with:
Marks
-----
Marks can be used apply meta data to *test functions* (but not fixtures), which can then be accessed by
fixtures or plugins.
.. _`pytest.mark.parametrize ref`:
pytest.mark.parametrize
~~~~~~~~~~~~~~~~~~~~~~~
**Tutorial**: :doc:`parametrize`.
.. automethod:: _pytest.python.Metafunc.parametrize
.. _`pytest.mark.skip ref`:
pytest.mark.skip
~~~~~~~~~~~~~~~~
**Tutorial**: :ref:`skip`.
Unconditionally skip a test function.
.. py:function:: pytest.mark.skip(*, reason=None)
:keyword str reason: Reason why the test function is being skipped.
.. _`pytest.mark.skipif ref`:
pytest.mark.skipif
~~~~~~~~~~~~~~~~~~
**Tutorial**: :ref:`xfail`.
Skip a test function if a condition is ``True``.
.. py:function:: pytest.mark.skipif(condition, *, reason=None)
:type condition: bool or str
:param condition: ``True/False`` if the condition should be skipped or a :ref:`condition string <string conditions>`.
:keyword str reason: Reason why the test function is being skipped.
.. _`pytest.mark.xfail ref`:
pytest.mark.xfail
~~~~~~~~~~~~~~~~~~
**Tutorial**: :ref:`xfail`.
Marks a test function as *expected to fail*.
.. py:function:: pytest.mark.xfail(condition=None, *, reason=None, raises=None, run=True, strict=False)
:type condition: bool or str
:param condition: ``True/False`` if the condition should be marked as xfail or a :ref:`condition string <string conditions>`.
:keyword str reason: Reason why the test function is marked as xfail.
:keyword Exception raises: Exception subclass expected to be raised by the test function; other exceptions will fail the test.
:keyword bool run:
If the test function should actually be executed. If ``False``, the function will always xfail and will
not be executed (useful a function is segfaulting).
:keyword bool strict:
* If ``False`` (the default) the function will be shown in the terminal output as ``xfailed`` if it fails
and as ``xpass`` if it passes. In both cases this will not cause the test suite to fail as a whole. This
is particularly useful to mark *flaky* tests (tests that random at fail) to be tackled later.
* If ``True``, the function will be shown in the terminal output as ``xfailed`` if it fails, but if it
unexpectedly passes then it will **fail** the test suite. This is particularly useful to mark functions
that are always failing and there should be a clear indication if they unexpectedly start to pass (for example
a new release of a library fixes a known bug).
custom marks
~~~~~~~~~~~~
Marks are created dynamically using the factory object ``pytest.mark`` and applied as a decorator.
For example:
.. code-block:: python
@pytest.mark.timeout(10, 'slow', method='thread')
def test_function():
...
Will create and attach a :class:`MarkInfo <_pytest.mark.MarkInfo>` object to the collected
:class:`Item <_pytest.nodes.Item>`, which can then be accessed by fixtures or hooks with
:meth:`Node.get_marker <_pytest.nodes.Node.get_marker>`. The ``mark`` object will have the following attributes:
.. code-block:: python
mark.args == (10, 'slow')
mark.kwargs == {'method': 'thread'}
Fixtures
--------
**Tutorial**: :ref:`fixture`.
Fixtures are requested by test functions or other fixtures by declaring them as argument names.
Example of a test requiring a fixture:
.. code-block:: python
def test_output(capsys):
print('hello')
out, err = capsys.readouterr()
assert out == 'hello\n'
Example of a fixture requiring another fixture:
.. code-block:: python
@pytest.fixture
def db_session(tmpdir):
fn = tmpdir / 'db.file'
return connect(str(fn))
For more details, consult the full :ref:`fixtures docs <fixture>`.
fixture decorator
~~~~~~~~~~~~~~~~~
.. currentmodule:: _pytest.fixtures
.. autofunction:: fixture
:decorator:
.. _`cache-api`:
config.cache
~~~~~~~~~~~~
**Tutorial**: :ref:`cache`.
The ``config.cache`` object allows other plugins and fixtures
to store and retrieve values across test runs. To access it from fixtures
request ``pytestconfig`` into your fixture and get it with ``pytestconfig.cache``.
Under the hood, the cache plugin uses the simple
``dumps``/``loads`` API of the :py:mod:`json` stdlib module.
.. currentmodule:: _pytest.cacheprovider
.. automethod:: Cache.get
.. automethod:: Cache.set
.. automethod:: Cache.makedir
capsys
~~~~~~
**Tutorial**: :doc:`capture`.
.. currentmodule:: _pytest.capture
.. autofunction:: capsys()
:no-auto-options:
Returns an instance of :py:class:`CaptureFixture`.
Example:
.. code-block:: python
def test_output(capsys):
print("hello")
captured = capsys.readouterr()
assert captured.out == "hello\n"
capsysbinary
~~~~~~~~~~~~
**Tutorial**: :doc:`capture`.
.. autofunction:: capsysbinary()
:no-auto-options:
Returns an instance of :py:class:`CaptureFixture`.
Example:
.. code-block:: python
def test_output(capsysbinary):
print("hello")
captured = capsysbinary.readouterr()
assert captured.out == b"hello\n"
capfd
~~~~~~
**Tutorial**: :doc:`capture`.
.. autofunction:: capfd()
:no-auto-options:
Returns an instance of :py:class:`CaptureFixture`.
Example:
.. code-block:: python
def test_system_echo(capfd):
os.system('echo "hello"')
captured = capsys.readouterr()
assert captured.out == "hello\n"
capfdbinary
~~~~~~~~~~~~
**Tutorial**: :doc:`capture`.
.. autofunction:: capfdbinary()
:no-auto-options:
Returns an instance of :py:class:`CaptureFixture`.
Example:
.. code-block:: python
def test_system_echo(capfdbinary):
os.system('echo "hello"')
captured = capfdbinary.readouterr()
assert captured.out == b"hello\n"
doctest_namespace
~~~~~~~~~~~~~~~~~
**Tutorial**: :doc:`doctest`.
.. autofunction:: _pytest.doctest.doctest_namespace()
Usually this fixture is used in conjunction with another ``autouse`` fixture:
.. code-block:: python
@pytest.fixture(autouse=True)
def add_np(doctest_namespace):
doctest_namespace['np'] = numpy
For more details: :ref:`doctest_namespace`.
request
~~~~~~~
**Tutorial**: :ref:`request example`.
The ``request`` fixture is a special fixture providing information of the requesting test function.
.. autoclass:: _pytest.fixtures.FixtureRequest()
:members:
pytestconfig
~~~~~~~~~~~~
.. autofunction:: _pytest.fixtures.pytestconfig()
record_xml_property
~~~~~~~~~~~~~~~~~~~
**Tutorial**: :ref:`record_xml_property example`.
.. autofunction:: _pytest.junitxml.record_xml_property()
caplog
~~~~~~
**Tutorial**: :doc:`logging`.
.. autofunction:: _pytest.logging.caplog()
:no-auto-options:
This returns a :class:`_pytest.logging.LogCaptureFixture` instance.
.. autoclass:: _pytest.logging.LogCaptureFixture
:members:
monkeypatch
~~~~~~~~~~~
.. currentmodule:: _pytest.monkeypatch
**Tutorial**: :doc:`monkeypatch`.
.. autofunction:: _pytest.monkeypatch.monkeypatch()
:no-auto-options:
This returns a :class:`MonkeyPatch` instance.
.. autoclass:: _pytest.monkeypatch.MonkeyPatch
:members:
testdir
~~~~~~~
.. currentmodule:: _pytest.pytester
This fixture provides a :class:`Testdir` instance useful for black-box testing of test files, making it ideal to
test plugins.
To use it, include in your top-most ``conftest.py`` file::
pytest_plugins = 'pytester'
.. autoclass:: Testdir()
:members: runpytest,runpytest_subprocess,runpytest_inprocess,makeconftest,makepyfile
.. autoclass:: RunResult()
:members:
.. autoclass:: LineMatcher()
:members:
recwarn
~~~~~~~
**Tutorial**: :ref:`assertwarnings`
.. currentmodule:: _pytest.recwarn
.. autofunction:: recwarn()
:no-auto-options:
.. autoclass:: _pytest.recwarn.WarningsRecorder()
:members:
Each recorded warning is an instance of :class:`warnings.WarningMessage`.
.. note::
:class:`RecordedWarning` was changed from a plain class to a namedtuple in pytest 3.1
.. note::
``DeprecationWarning`` and ``PendingDeprecationWarning`` are treated
differently; see :ref:`ensuring_function_triggers`.
tmpdir
~~~~~~
**Tutorial**: :doc:`tmpdir`
.. currentmodule:: _pytest.tmpdir
.. autofunction:: tmpdir()
:no-auto-options:
tmpdir_factory
~~~~~~~~~~~~~~
**Tutorial**: :ref:`tmpdir factory example`
.. _`tmpdir factory api`:
``tmpdir_factory`` instances have the following methods:
.. currentmodule:: _pytest.tmpdir
.. automethod:: TempdirFactory.mktemp
.. automethod:: TempdirFactory.getbasetemp
.. _`hook-reference`:
Hooks
-----
**Tutorial**: :doc:`writing_plugins`.
.. currentmodule:: _pytest.hookspec
Reference to all hooks which can be implemented by :ref:`conftest.py files <localplugin>` and :ref:`plugins <plugins>`.
Bootstrapping hooks
~~~~~~~~~~~~~~~~~~~
Bootstrapping hooks called for plugins registered early enough (internal and setuptools plugins).
.. autofunction:: pytest_load_initial_conftests
.. autofunction:: pytest_cmdline_preparse
.. autofunction:: pytest_cmdline_parse
.. autofunction:: pytest_cmdline_main
Initialization hooks
~~~~~~~~~~~~~~~~~~~~
Initialization hooks called for plugins and ``conftest.py`` files.
.. autofunction:: pytest_addoption
.. autofunction:: pytest_configure
.. autofunction:: pytest_unconfigure
Test running hooks
~~~~~~~~~~~~~~~~~~
All runtest related hooks receive a :py:class:`pytest.Item <_pytest.main.Item>` object.
.. autofunction:: pytest_runtestloop
.. autofunction:: pytest_runtest_protocol
.. autofunction:: pytest_runtest_logstart
.. autofunction:: pytest_runtest_logfinish
.. autofunction:: pytest_runtest_setup
.. autofunction:: pytest_runtest_call
.. autofunction:: pytest_runtest_teardown
.. autofunction:: pytest_runtest_makereport
For deeper understanding you may look at the default implementation of
these hooks in :py:mod:`_pytest.runner` and maybe also
in :py:mod:`_pytest.pdb` which interacts with :py:mod:`_pytest.capture`
and its input/output capturing in order to immediately drop
into interactive debugging when a test failure occurs.
The :py:mod:`_pytest.terminal` reported specifically uses
the reporting hook to print information about a test run.
Collection hooks
~~~~~~~~~~~~~~~~
``pytest`` calls the following hooks for collecting files and directories:
.. autofunction:: pytest_collection
.. autofunction:: pytest_ignore_collect
.. autofunction:: pytest_collect_directory
.. autofunction:: pytest_collect_file
For influencing the collection of objects in Python modules
you can use the following hook:
.. autofunction:: pytest_pycollect_makeitem
.. autofunction:: pytest_generate_tests
.. autofunction:: pytest_make_parametrize_id
After collection is complete, you can modify the order of
items, delete or otherwise amend the test items:
.. autofunction:: pytest_collection_modifyitems
Reporting hooks
~~~~~~~~~~~~~~~
Session related reporting hooks:
.. autofunction:: pytest_collectstart
.. autofunction:: pytest_itemcollected
.. autofunction:: pytest_collectreport
.. autofunction:: pytest_deselected
.. autofunction:: pytest_report_header
.. autofunction:: pytest_report_collectionfinish
.. autofunction:: pytest_report_teststatus
.. autofunction:: pytest_terminal_summary
.. autofunction:: pytest_fixture_setup
.. autofunction:: pytest_fixture_post_finalizer
And here is the central hook for reporting about
test execution:
.. autofunction:: pytest_runtest_logreport
You can also use this hook to customize assertion representation for some
types:
.. autofunction:: pytest_assertrepr_compare
Debugging/Interaction hooks
~~~~~~~~~~~~~~~~~~~~~~~~~~~
There are few hooks which can be used for special
reporting or interaction with exceptions:
.. autofunction:: pytest_internalerror
.. autofunction:: pytest_keyboard_interrupt
.. autofunction:: pytest_exception_interact
.. autofunction:: pytest_enter_pdb
Objects
-------
Full reference to objects accessible from :ref:`fixtures <fixture>` or :ref:`hooks <hook-reference>`.
CallInfo
~~~~~~~~
.. autoclass:: _pytest.runner.CallInfo()
:members:
Class
~~~~~
.. autoclass:: _pytest.python.Class()
:members:
:show-inheritance:
Collector
~~~~~~~~~
.. autoclass:: _pytest.nodes.Collector()
:members:
:show-inheritance:
Config
~~~~~~
.. autoclass:: _pytest.config.Config()
:members:
ExceptionInfo
~~~~~~~~~~~~~
.. autoclass:: _pytest._code.ExceptionInfo
:members:
FixtureDef
~~~~~~~~~~
.. autoclass:: _pytest.fixtures.FixtureDef()
:members:
:show-inheritance:
FSCollector
~~~~~~~~~~~
.. autoclass:: _pytest.nodes.FSCollector()
:members:
:show-inheritance:
Function
~~~~~~~~
.. autoclass:: _pytest.python.Function()
:members:
:show-inheritance:
Item
~~~~
.. autoclass:: _pytest.nodes.Item()
:members:
:show-inheritance:
MarkDecorator
~~~~~~~~~~~~~
.. autoclass:: _pytest.mark.MarkDecorator
:members:
MarkGenerator
~~~~~~~~~~~~~
.. autoclass:: _pytest.mark.MarkGenerator
:members:
MarkInfo
~~~~~~~~
.. autoclass:: _pytest.mark.MarkInfo
:members:
Metafunc
~~~~~~~~
.. autoclass:: _pytest.python.Metafunc
:members:
Module
~~~~~~
.. autoclass:: _pytest.python.Module()
:members:
:show-inheritance:
Node
~~~~
.. autoclass:: _pytest.nodes.Node()
:members:
Parser
~~~~~~
.. autoclass:: _pytest.config.Parser()
:members:
PluginManager
~~~~~~~~~~~~~
.. autoclass:: pluggy.PluginManager()
:members:
PytestPluginManager
~~~~~~~~~~~~~~~~~~~
.. autoclass:: _pytest.config.PytestPluginManager()
:members:
:undoc-members:
:show-inheritance:
Session
~~~~~~~
.. autoclass:: _pytest.main.Session()
:members:
:show-inheritance:
TestReport
~~~~~~~~~~
.. autoclass:: _pytest.runner.TestReport()
:members:
:inherited-members:
_Result
~~~~~~~
.. autoclass:: pluggy._Result
:members: