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Pierre Sassoulas 1125296b53 Small performance/readability improvments when iterating dictionnary with ``keys()``
Based on pylint's message ``consider-iterating-dictionary`` suggestion.
Surprisingly using a dict or set comprehension instead of a new temp var is
actually consistently slower here, which was not intuitive for me.

```python
from timeit import timeit

families = {1: {"testcase": [1, 2, 3, 5, 8]}}
attrs = {1: "a", 2: "b", 3: "c", 4: "d", 5: "e", 6: "f", 7: "g", 8: "h"}

class Old:
    def old(self):
        self.attrs = attrs
        temp_attrs = {}
        for key in self.attrs.keys():
            if key in families[1]["testcase"]:
                temp_attrs[key] = self.attrs[key]
        self.attrs = temp_attrs

class OldBis:
    def old(self):
        self.attrs = attrs
        temp_attrs = {}
        for key in self.attrs:
            if key in families[1]["testcase"]:
                temp_attrs[key] = self.attrs[key]
        self.attrs = temp_attrs

class New:
    def new(self):
        self.attrs = attrs
        self.attrs = { # Even worse with k: v for k in self.attrs.items()
            k: self.attrs[k] for k in self.attrs if k in families[1]["testcase"]
        }

if __name__ == "__main__":
    n = 1000000
    print(f"Old: {timeit(Old().old, number=n)}")
    print(f"Just removing the keys(): {timeit(OldBis().old, number=n)}")
    print(f"List comp, no temp var: {timeit(New().new, number=n)}")
```

Result:
Old: 0.9493889989680611
Just removing the keys(): 0.9042672360083088
List comp, no temp var: 0.9916125109884888

It's also true for the other example with similar benchmark, but the exact
code probably does not need to be in the commit message.
2024-03-31 14:43:07 +02:00
.github Merge pull request #12133 from pytest-dev/dependabot/github_actions/hynek/build-and-inspect-python-package-2.0.2 2024-03-20 11:21:40 +02:00
bench Enable lint PGH004 - Use specific rule codes when using noqa 2024-02-09 11:14:36 +02:00
changelog Don't reregister subfixture finalizer in requested fixture if value is cached (#12136) 2024-03-31 15:02:09 +03:00
doc/en Improve sentence in marks documentation (#12157) 2024-03-24 15:59:07 +01:00
extra Migrate from autoflake, black, isort, pyupgrade, flake8 and pydocstyle, to ruff 2024-02-02 09:27:00 +01:00
scripts [pre-commit.ci] pre-commit autoupdate (#12115) 2024-03-13 15:30:18 +02:00
src Small performance/readability improvments when iterating dictionnary with ``keys()`` 2024-03-31 14:43:07 +02:00
testing Don't reregister subfixture finalizer in requested fixture if value is cached (#12136) 2024-03-31 15:02:09 +03:00
.coveragerc coverage: add assert_never to exclude_lines 2021-10-02 14:26:04 +03:00
.git-blame-ignore-revs [.git-blame-ignore-revs] Add migration to ruff/ruff format and blacken-docs 2024's style 2024-02-02 09:28:09 +01:00
.gitattributes Add codecov support to AppVeyor and remove coveralls 2018-09-05 19:50:06 -03:00
.gitignore Parse args from file (#12085) 2024-03-09 08:51:52 +02:00
.pre-commit-config.yaml [tooling] Add a manual step to run pylint in pre-commit 2024-03-31 14:43:07 +02:00
.readthedocs.yml Configure ReadTheDocs to fail on warnings (#11535) 2023-10-23 09:56:33 -03:00
AUTHORS Parse args from file (#12085) 2024-03-09 08:51:52 +02:00
CHANGELOG.rst port the rest of the scripts/docs over to the main branch 2021-03-18 22:13:12 +01:00
CITATION Fix linting issues 2018-07-14 16:35:33 +01:00
CODE_OF_CONDUCT.md remove myself from the list of coc handlers (#6857) 2020-03-03 19:08:59 -03:00
CONTRIBUTING.rst Rename 'testing' extra to 'dev' (#12052) 2024-03-07 19:12:19 -03:00
LICENSE Change copyright notice so yearly updates are not needed 2021-11-30 09:28:23 -03:00
OPENCOLLECTIVE.rst doc: fix typos in OPENCOLLECTIVE.rst [ci skip] 2019-07-10 20:15:22 +02:00
README.rst docs: update plugins number 2024-03-01 05:43:57 +08:00
RELEASING.rst Adjustments to the release process (#11410) 2023-09-08 07:22:16 -03:00
TIDELIFT.rst add myself to tidelift 2024-03-04 12:59:54 +01:00
codecov.yml Adjust codecov: only patch statuses 2020-06-02 08:17:43 -03:00
pyproject.toml Small performance/readability improvments when iterating dictionnary with ``keys()`` 2024-03-31 14:43:07 +02:00
tox.ini Rename 'testing' extra to 'dev' (#12052) 2024-03-07 19:12:19 -03:00

README.rst

.. image:: https://github.com/pytest-dev/pytest/raw/main/doc/en/img/pytest_logo_curves.svg
   :target: https://docs.pytest.org/en/stable/
   :align: center
   :height: 200
   :alt: pytest


------

.. image:: https://img.shields.io/pypi/v/pytest.svg
    :target: https://pypi.org/project/pytest/

.. image:: https://img.shields.io/conda/vn/conda-forge/pytest.svg
    :target: https://anaconda.org/conda-forge/pytest

.. image:: https://img.shields.io/pypi/pyversions/pytest.svg
    :target: https://pypi.org/project/pytest/

.. image:: https://codecov.io/gh/pytest-dev/pytest/branch/main/graph/badge.svg
    :target: https://codecov.io/gh/pytest-dev/pytest
    :alt: Code coverage Status

.. image:: https://github.com/pytest-dev/pytest/actions/workflows/test.yml/badge.svg
    :target: https://github.com/pytest-dev/pytest/actions?query=workflow%3Atest

.. image:: https://results.pre-commit.ci/badge/github/pytest-dev/pytest/main.svg
   :target: https://results.pre-commit.ci/latest/github/pytest-dev/pytest/main
   :alt: pre-commit.ci status

.. image:: https://www.codetriage.com/pytest-dev/pytest/badges/users.svg
    :target: https://www.codetriage.com/pytest-dev/pytest

.. image:: https://readthedocs.org/projects/pytest/badge/?version=latest
    :target: https://pytest.readthedocs.io/en/latest/?badge=latest
    :alt: Documentation Status

.. image:: https://img.shields.io/badge/Discord-pytest--dev-blue
    :target: https://discord.com/invite/pytest-dev
    :alt: Discord

.. image:: https://img.shields.io/badge/Libera%20chat-%23pytest-orange
    :target: https://web.libera.chat/#pytest
    :alt: Libera chat


The ``pytest`` framework makes it easy to write small tests, yet
scales to support complex functional testing for applications and libraries.

An example of a simple test:

.. code-block:: python

    # content of test_sample.py
    def inc(x):
        return x + 1


    def test_answer():
        assert inc(3) == 5


To execute it::

    $ pytest
    ============================= test session starts =============================
    collected 1 items

    test_sample.py F

    ================================== FAILURES ===================================
    _________________________________ test_answer _________________________________

        def test_answer():
    >       assert inc(3) == 5
    E       assert 4 == 5
    E        +  where 4 = inc(3)

    test_sample.py:5: AssertionError
    ========================== 1 failed in 0.04 seconds ===========================


Due to ``pytest``'s detailed assertion introspection, only plain ``assert`` statements are used. See `getting-started <https://docs.pytest.org/en/stable/getting-started.html#our-first-test-run>`_ for more examples.


Features
--------

- Detailed info on failing `assert statements <https://docs.pytest.org/en/stable/how-to/assert.html>`_ (no need to remember ``self.assert*`` names)

- `Auto-discovery
  <https://docs.pytest.org/en/stable/explanation/goodpractices.html#python-test-discovery>`_
  of test modules and functions

- `Modular fixtures <https://docs.pytest.org/en/stable/explanation/fixtures.html>`_ for
  managing small or parametrized long-lived test resources

- Can run `unittest <https://docs.pytest.org/en/stable/how-to/unittest.html>`_ (or trial)
  test suites out of the box

- Python 3.8+ or PyPy3

- Rich plugin architecture, with over 1300+ `external plugins <https://docs.pytest.org/en/latest/reference/plugin_list.html>`_ and thriving community


Documentation
-------------

For full documentation, including installation, tutorials and PDF documents, please see https://docs.pytest.org/en/stable/.


Bugs/Requests
-------------

Please use the `GitHub issue tracker <https://github.com/pytest-dev/pytest/issues>`_ to submit bugs or request features.


Changelog
---------

Consult the `Changelog <https://docs.pytest.org/en/stable/changelog.html>`__ page for fixes and enhancements of each version.


Support pytest
--------------

`Open Collective`_ is an online funding platform for open and transparent communities.
It provides tools to raise money and share your finances in full transparency.

It is the platform of choice for individuals and companies that want to make one-time or
monthly donations directly to the project.

See more details in the `pytest collective`_.

.. _Open Collective: https://opencollective.com
.. _pytest collective: https://opencollective.com/pytest


pytest for enterprise
---------------------

Available as part of the Tidelift Subscription.

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Save time, reduce risk, and improve code health, while paying the maintainers of the exact dependencies you use.

`Learn more. <https://tidelift.com/subscription/pkg/pypi-pytest?utm_source=pypi-pytest&utm_medium=referral&utm_campaign=enterprise&utm_term=repo>`_

Security
^^^^^^^^

pytest has never been associated with a security vulnerability, but in any case, to report a
security vulnerability please use the `Tidelift security contact <https://tidelift.com/security>`_.
Tidelift will coordinate the fix and disclosure.


License
-------

Copyright Holger Krekel and others, 2004.

Distributed under the terms of the `MIT`_ license, pytest is free and open source software.

.. _`MIT`: https://github.com/pytest-dev/pytest/blob/main/LICENSE