test_ok2/doc/en/builtin.rst

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.. _`pytest helpers`:
Pytest API and builtin fixtures
================================================
This is a list of ``pytest.*`` API functions and fixtures.
For information on plugin hooks and objects, see :ref:`plugins`.
For information on the ``pytest.mark`` mechanism, see :ref:`mark`.
For the below objects, you can also interactively ask for help, e.g. by
typing on the Python interactive prompt something like::
import pytest
help(pytest)
.. currentmodule:: pytest
Invoking pytest interactively
---------------------------------------------------
.. autofunction:: main
More examples at :ref:`pytest.main-usage`
Helpers for assertions about Exceptions/Warnings
--------------------------------------------------------
.. autofunction:: raises
Examples at :ref:`assertraises`.
.. autofunction:: deprecated_call
Raising a specific test outcome
--------------------------------------
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`.
.. autofunction:: _pytest.runner.fail
.. autofunction:: _pytest.runner.skip
.. autofunction:: _pytest.runner.importorskip
.. autofunction:: _pytest.skipping.xfail
.. autofunction:: _pytest.runner.exit
fixtures and requests
-----------------------------------------------------
To mark a fixture function:
.. autofunction:: _pytest.python.fixture
Tutorial at :ref:`fixtures`.
The ``request`` object that can be used from fixture functions.
.. autoclass:: _pytest.python.FixtureRequest()
:members:
.. _builtinfixtures:
.. _builtinfuncargs:
Builtin fixtures/function arguments
-----------------------------------------
You can ask for available builtin or project-custom
:ref:`fixtures <fixtures>` by typing::
$ py.test -q --fixtures
capsys
enables capturing of writes to sys.stdout/sys.stderr and makes
captured output available via ``capsys.readouterr()`` method calls
which return a ``(out, err)`` tuple.
capfd
enables capturing of writes to file descriptors 1 and 2 and makes
captured output available via ``capfd.readouterr()`` method calls
which return a ``(out, err)`` tuple.
monkeypatch
The returned ``monkeypatch`` funcarg provides these
helper methods to modify objects, dictionaries or os.environ::
monkeypatch.setattr(obj, name, value, raising=True)
monkeypatch.delattr(obj, name, raising=True)
monkeypatch.setitem(mapping, name, value)
monkeypatch.delitem(obj, name, raising=True)
monkeypatch.setenv(name, value, prepend=False)
monkeypatch.delenv(name, value, raising=True)
monkeypatch.syspath_prepend(path)
monkeypatch.chdir(path)
All modifications will be undone after the requesting
test function has finished. The ``raising``
parameter determines if a KeyError or AttributeError
will be raised if the set/deletion operation has no target.
pytestconfig
the pytest config object with access to command line opts.
recwarn
Return a WarningsRecorder instance that provides these methods:
* ``pop(category=None)``: return last warning matching the category.
* ``clear()``: clear list of warnings
See http://docs.python.org/library/warnings.html for information
on warning categories.
tmpdir
return a temporary directory path object
which is unique to each test function invocation,
created as a sub directory of the base temporary
directory. The returned object is a `py.path.local`_
path object.
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